Is a calorie always a calorie?

Over the past few weeks I’ve taken some heat in the comments section for my writing that weight loss or weight gain involves more than a simple accounting for calories. The entirety of mainstream medicine and nutrition believe that calories are the only thing that counts and that a low-carb diet is nothing more than a clever way to get people to cut calories. Weight loss on low-carb diets, so they say, occurs only because subjects following low-carb diets reduce their caloric intake. A calorie is a calorie is a calorie they say. But is it?

I could argue that this idea isn’t necessarily true because of a number of recent studies that have shown that subjects following low-carb diets actually lose more weight than their counterparts on low-fat, high carb diets despite the fact that the low-carbers consumed considerably more calories. But instead of going through these modern day studies, let’s go back and look at a couple of earlier famous studies to see what we can learn.


In 1944 Ancel Keys, Ph.D., decided to undertake a long-term study of starvation. It was apparent that WWII was going to be over soon and that much of Europe was starving. Although word of the mass starvation in concentration camps was just starting to filter out into the world, it was well known the Europeans, especially Eastern European, were not getting enough food. Keys wanted to do a study of starvation to see what really happened during the process so that at war’s end the victors would have a better idea of how to deal with the starving masses they were sure to encounter.

Key’s recruited 36 young male volunteers from the cadre of the conscientious objectors. These were healthy, normal weight men, most of whom were working for the Civilian Public Service (CPS), an entity created to provide jobs of national importance for conscientious objectors. The men responded to brochures and bulletins distributed in the various CPS barracks showing a photo of three French toddlers staring at empty bowls over the question: WILL YOU STARVE SO THAT THEY WILL BE BETTER FED?

The subjects came to the University of Minnesota where they were housed in the cavernous area underneath the football stadium for the course of the study. They were basically kept under lock and key for the study so that Keys and his colleagues could ensure compliance. At the start of the experiment the men were fed sumptuously for the first 12 weeks.

A full-time cook, two assistants and a dietitian monitored the food intake to the smallest fraction. According to The Great Starvation Experiment**, an excellent book about this famous study, during this lead-in phase the men ate well. A typical days food would include

a typical lunch… [that] consisted of fricasseed lamb with gravy, peas, and a carrot and raisin salad. For dinner…the men ate roast beef with gravy, whipped potatoes, tomato salad, and ice cream for dessert.

Although the three meals per day the men received added up to around 3,200 calories, which they were told approximated the normal American diet, the men said that they had never eaten better in their lives.

On day one of the starvation portion of the study, February 12, 1945, the rations were cut substantially.

The group shifted overnight from the three relatively generous meals of the control period to only two Spartan meals per day, a breakfast at 8:30 AM and supper at 5:00 PM.

The meals were designed to approximate the food available in European famine areas, with a heavy emphasis on potatoes, cabbage, and whole wheat bread. Meat was provided in quantities so small that most men would swear in later years that none was included at all.

One of the three dinners included the following:


185 grams of bean-and pea soup (made with 5 grams dried peas, 16 grams of dried beans, and 15 grams fresh ham)

255 grams macaroni and cheese (made with 130 grams wet macaroni, 12 grams lard, 108 grams skim milk, 2 grams flour, and 35 grams American cheese)

40 grams rutabagas

100 grams steamed potatoes

100 grams lettuce salad (80 grams lettuce, 10 grams vinegar, 10 grams sugar)

The relatively bulky 255 grams of macaroni made that particular meal an anticipated favorite among the volunteers. The wet macaroni served was roughly the amount required to fill a coffee mug about three-quarters full.

Over the twenty-four week starvation part of the study, the subjects not only lost a considerable percentage of their body weights, but suffered a number of problems as well. As the time wore on the men thought ceaselessly about food, they became lethargic, they were cold all the time, they became depressed, they developed bleeding disorders, their ankles became edematous, and some developed more serious psychological disorders.

Below is a photo of one of the young men in this study (the book shows multiple photographs – this one is typical of all the subjects). The first photo was taken a couple of years prior to the start of the study, the second is with about a month shy of the end of the experiment.


This young man suffered such psychological turmoil from the semi-starvation that he chopped off several fingers of his left hand a month or so after the bottom picture was taken.

The men in this study consumed macronutrients in the following amounts daily: protein 100 gm, fat 30 gm, and carbohydrate 225 gm. If you express these intakes as percentages, you come up with 25.5% protein, 17.2% fat and 57.3% carbohydrate.

Average energy intake of the subjects in the experiment: 1570 calories per day.

Now let’s look at another experiment conducted about 25 years later.


In the late 1960s John Yudkin’s group at the University of London performed a study that is most interesting in view of the Keys’ semi-starvation study. (Click here to get the complete pdf of this study)

For about 15 years Dr. Yudkin and his team had been running a weight loss clinic out of the university hospital using a low-carb dietary approach. Despite the patients’ doing well on the program, he and his staff had received the same criticisms all of us have who treat obese patients by restricting carbohydrates. In addition, because of his academic standing and long list of scientific publications, Yudkin’s peers had given him heat over the fact that his diet didn’t provide enough of all the vitamins and minerals required for health. As a consequence, he decided to do a study to see if there was any substance to their fault-finding.

He recruited 11 subjects aged 21-51 years for his study. He and his staff evaluated the regular diets of these 11 subjects over a two week period. The volunteers were then instructed on the basics of low-carb dieting as it was done in the hospital clinic and followed for two weeks on this regimen. The goal of the study was to determine the dietary intake of the essential nutrients in the low-carb diet to see if there were inadequacies.

Here were the low-carb instructions:

The instructions relating to the low carbohydrate diet were identical to those given to patients attending a hospital overweight clinic under our supervision. Essentially, the subjects were asked to take between 10 and 20 oz milk daily (about 300-600 ml), and as much meat, fish, eggs, cheese, butter, margarine, cream and leafy vegetables as they wished. The amount of carbohydrate in other food was listed in “units” with each unit consisting of 5 g carbohydrate; the subjects were told to limit these foods to not more than 10 units (or 50 g) carbohydrate daily.

As the low-carb portion of the study was progressing, Yudkin and his staff evaluated not only the intake of these subjects, but their mental status as well.

In conformity with our experience with this diet during the last 15 years, none of our subjects complained of hunger or any other ill effects; on the other hand, several volunteered statements to the effect that they had increased feeling of well-being and decreased lassitude. The average intake of calories and of protein, fat, and carbohydrate for the 11 subjects…were remarkably similar to those obtained for the six subjects of the previous study. [Yudkin had published a study in The Lancet in 1960 looking at the caloric and macronutrient intake of subjects on low-carb diets.]

Here is the chart from Yudkin’s paper showing the caloric and macronutrient changes when the subjects shifted from their regular diet to the low-carbohydrate diet.


The macronutrient consumption was 83 grams of protein, 105 grams of fat and 67 grams of carbohydrate. Putting this into percentages of overall intake, we find that diet was 21.3% protein, 60.6% fat and 17.1% carbohydrate. The energy intake was 1560 calories per day, almost exactly the same as the Keys study described above.

And, remember, these people were given all the food they wanted to eat. They weren’t forced to drop their calories to 1560 per day – they did it spontaneously because they had eaten until sated.

Here is the data in tabular form.


As you can see, the big difference is in the carbohydrate intake and fat intake. They are just about the reverse of one another in the two studies.

Both studies provided between 1500 and 1600 kcal per day, but with huge differences in outcome. In the Key’s semi-starvation study (high-carb, low-fat) the subjects starved and obsessed on food constantly. In the Yudkin study (low-carb, high-fat), the subjects, who had no restriction on the amount of food they ate, volitionally consumed the same number of calories that the semi-starvation group did, yet reported that they had “an increases feeling of well-being.” Instead of lethargy and depression reported by the Keys subjects on their low-fat, high-carb 1570 calories, those on the same number of low-carb, high-fat calories experienced “decreased lassitude.”

Both groups of subjects were consuming the same number of calories, but one group starved while the other did just fine. One group had to be locked down to ensure they didn’t eat more than their alloted 1570 calories; the other group voluntarily dropped their intake to 1560 calories and felt great. What was the difference? Subjects in both groups ate the same number of calories.

Maybe, just maybe it’s not the number of calories that makes the difference, but the composition of the calories instead.

I know that I’m not truly comparing apples to apples with the Keys and the Yudkin studies.  But the Yudkin study does confirm Yudkin’s 15 years of experience before he wrote his paper and they confirm my 20 plus years of experience taking care of patients on low-carb diets. I’ve had many, many patients who have stayed on low-carb diets for much, much longer than the men in Keys’ experiment stayed on their diets of roughly the same number of calories. Most of the papers in the medical literature on low-carb diets show a spontaneous drop in caloric intake that’s about what Yudkin documented when people switch over to low-carb diets. It stands to reason that if someone had replicated Keys’ experiment using the same number of calories, but with much more fat and a lot less carbohydrate, that the outcome would have been much different.

Yet the calories would have been the same.

So, I’ll say it again. It’s not simply a matter of calories, and anyone who says it is should perhaps give the issue a little more thought.

** Gary Taubes’ new book Good Calories, Bad Calories devotes a couple of pages to this semi-starvation study as well.

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81 thoughts on “Is a calorie always a calorie?

  1. Check mate! Every dietitian on the planet should read this, doc.

    Oh, and you wrote 25 instead of 225 gm of carbs for the Keys study (don’t publish this, it will be our little secret… HA!)

    Thanks for the heads up. I fixed the typo.



  2. Another great post, Doc. Thanks.

    Here is some more personal testimony. I’ve been on a serious LC/IF
    “test” for about a month now ( I don’t weigh myself, I just watch my
    clothes get bigger 🙂 ). I can say with certainty that not only am I not
    hungry on non-IF days, I am not hungry at all on IF days, and when I
    break the IF around 6pm, I only want to eat a “normal” LC meal.
    The next morning, I almost feel guilty facing the 3 meal day. Seems too
    much to eat. Go figure. So, I can’t identify AT ALL with the moods of those poor
    Ancel Keys folks, though I am sure my daily cal total is not much different from theirs.
    Has to either be the types of calories, or maybe also the
    fact that what they were on was being called “starvation”, and that
    had some unmeasured negative psychological effect on them?


    I wondered about the negative psychological effect myself…then I saw the pictures. I think a lot more is going on than anything caused by the negative effect of the diet being called a starvation diet.

    Glad to hear you’re doing so well.



  3. These studies always come to mind whenever I see people following a low-fat diet who complain of depression. I wonder how much of it has to do with hormones, both the overproduction of some and underproduction of others, as a result of the carbs. My best guess is that it is the inclusion of carbs and not the lack of fat (or maybe a combo?) that is troubling because those who fast for long periods do not have such troubles.

    This brings to mind something I have noticed in myself Whenever I eat a breakfast of eggs I find that I feel much more satisfied than if I eat pork chops. Then I found this:

    According to the study, meats like beef and fish provoke a much greater insulin response than do eggs. Is this accurate and do low carbers have anything to worry about here?


    Hi Freddy–

    I don’t think low-carbers have anything to worry about with the meat verses eggs issue. In fact, the study you linked shows insulin response, but not glucagon response, and it’s the ratio of the two that is important. And, like the studies on the glycemic index, it’s difficult to draw conclusions from the evaluation of single foods because most people eat mixed meals, not single foods.



  4. That’s nothing short of frightening, that taking your calories as carbs does that to humans! It would be be hard to believe, but for the fact I don’t doubt your word.

    Strange but true.

  5. great stuff!


    …how do you know really how many calories the low carb group ate? It doesnt sound like the low carb group in the Yudkin study were controlled that tightly, if at all, as far as calories consumed. I know when I eat all I want under similar rules (except no milk, please..) I can easily down more than 1500 or so calories. In fact, I have to actively watch myself to keep it that low.

    One more thing, there’s a gentleman in Australia, Anthony Colpo, who makes a big fuss about metabolic ward studies as definitive proof that there’s no advantage to low carb diets, in regards to the old calories in/calories out business. Any opinions?

    Hi mrfreddy–

    I don’t know how many calories the low-carb group ate because I wasn’t there to count them. But John Yudkin is a well known, well thought of researcher who used not FFQs but detailed food diaries so I have no reason to doubt his data. The people on the study had no reason to underreport, and, in fact, there reporting on their normal diets was pretty spot on in terms of the average diet.

    I’m very familiar with Anthony Colpo and his work. I think he’s a very smart guy and I think he’s right on the money on a lot of issues, but I think he’s wrong on this one. If you give one group of people a 2000 kcal diet and another a 1500 kcal diet of the same composition, the ones on the 1500 kcal diet will unquestionably lose more weight. If you start changing the diet composition, though, your outcome may change.



  6. You might find this interesting. Page 70 of the October 2007 “Men’s Journal” magazine provides a very short, but surprisingly open-minded review of “Good Calories, Bad Calories”– for example:

    “This isn’t just another Atkins manifesto; Taubes spends 640 meticulously researched pages arguing that carbs are responsible for just about every disease known to civilization…”


    “Hanson (a professor of biochemistry at Case Western University) agrees with Taubes’s argument about carbs, as do plenty of other experts…”

    Who knows, perhaps the light of truly healthy eating will burn more brightly in the coming months.

    We can only hope.



  7. The first time I went on the Protein Power diet happened to be right after I had tried mightily to lose weight on a recommended low-fat diet. To keep track of what I was doing, I had downloaded this nifty diet tracking software. I can’t remember what it was called but it was great — Dietwatch, maybe? This was in the late 1990s. It used to be free and very easy to use.

    The point is I had kept track of what I ate for several weeks on the low-fat diet. I was consuming about 1700-1750 calories a day and was losing half a pound a week, if that. It was very frustrating, and I was hungry all the time. I’m certain I must have been consuming over 60% of my calories in the form of carbs.

    Then I switched to Protein Power (yay!) and felt better, lost weight, etc. People said, “Oh, it’s just because you’re eating less calories. That’s all it is.”

    I still had the software and my old low-fat records, so I decided to keep track of what I was eating on the Protein Power diet to see if they were right. I’m sure it will not surprise you to learn that I was actually consuming MORE calories than I had been on the low-fat diet — a total of about 1800-1850 calories a day — but I was losing 2 to 2.5 pounds a week!

    It mostly didn’t matter, though. What people believed, they continued to believe.

    Another great post. Thanks! –Anne

    Hi Anne–

    Thanks for the dietary history. It’s right in line with what many of the studies comparing low-carb to low-fat show.



  8. The information (nutrient compisition and total calories) about the food eaten by the subjects in the Yudkin study was bases self-reported food intake? or is it just the amounts they were instructed to eat?

    They were allowed to eat ad libitum as long as they kept carbohydrates within limits. They weren’t instructed to eat any specific amounts.

  9. I’m relatively new to low-carbing, so this might sound stupid:

    Why would a high-carb, relatively low-calorie diet result in starvation, but not if it’s low-carb? Does that mean that the calories are not absorbed equally? Where do the calories go? And I thought that high-carb diets are fattening? Or is there a threshold amount before the fat begins to accumulate?


    Hi Anna–

    You’ve asked a lot of questions that are beyond the scope of the comment section. Gary Taubes has written a 640 page book dealing with these questions specifically.



  10. Thank you Dr. Mike! I truly believe all calories are not equal.. just as all carbohydrates are not equal. I have lost weight eating close to 2000 calories on a low-carb diet. I have consumed around 1500 calories on a low-fat diet and lost nothing but time. :0)

    You and a lot of others.

  11. Hi again Mike,

    I’m really trying not to be argumentative … honest! But what is your point? First of all you know you are preaching to the choir in terms of the health advantages of low carb. You complain that low carb critics state that weight loss on this plan is all about the ad libitum calorie restriction it routinely provides – why complain? – I always laugh when I read about this ‘defect’ – from people who are trying to force you to cut calories the hard way! If you could bottle even that aspect of low carb you’d make Bill Gates look like a pauper.

    Anyway – so to prove these critics wrong (that low carb doesn’t cause ad libitum calorie restriction?) you post two (of many) studies that show fairly conclusively that it does! If you want to get into the calorie is not a calorie argument – that is some form of low carb metabolic advantage provides an additional advantage over the health/hunger factors these studies address, surely you would need some data on the weight loss experienced on each diet. Maybe Yudikin’s subjects lost more weight for the same calories (although credit where it’s due the Keys plan certainly caused massive weight loss!) – maybe not – there is no data to compare the two.

    Yes there are studies that seem to show this – but all (AFAIK) rely on self reporting of intake, which which ever way it is recorded is never satisfactory, as I’m sure you will agree. There was a recent study in rats that showed some promise, but as I’ve said before, how difficult would it be to prove this once and for all in a highly controlled environment? Again AFAIK the only studies done in this manner (albeit they tend to be very low calorie studies – is this a problem?) have shown no weight loss advantage from different macro nutrient intake.

    But please prove me (and them) wrong!



    I posted to show the difference between low-carb calories and low-fat calories in terms of appetite and body composition. I’ve never said – I don’t think – that carb restriction doesn’t cause a spontaneous reduction in caloric intake because it does. But, I’m not sure that all the weight loss that comes from low-carb diets comes about simply because of the spontaneous calorie restriction. I think it comes about because of a) the decreased caloric intake, and b) because of an increase in metabolic rate, and c) because it stimulates an urge in low-carb dieters to be more active.



  12. I have been reading your blog for awhile and even if I disagree with some of what you write, regarding this subject, you are absolutely correct.

    Human nutrition is much more intricate and complex than just calories in and calories out, calories are not equal. Even the macronutrients themselfs are not equal. Take carbs: the effect a gram of fructose has on the body differs greatly from the effect of a gram of starch. The same can be said about a gram of fat (a gram of poly unsaturated fat and a gram of saturated fat, do they have the same effect on the organism?) The BV of protein pretty much proves that a gram of protein is not just a gram of protein. And if you start analyzing specific micronutrients from mineral to vitamins you will have an idea of just how complex everything is.

    The truth is you can have a healthy and rich 1600 cal diet if you are able to juggle all the parameters or you can have a 3000 diet completely devoid of essential nutrients.

    Immanuel D’antelo

    Hi Immanuel–

    First, you are right on the money with your last sentence; second, how could you possibly disagree with anything I write?



  13. The protein in the Keys diet seems dangerously high.
    A modern dietitian would probably want to bring the protein down to ten percent, thats 37.5 grams, if you wanted to give Dean Ornish and his posse a fair trial. No?

    That’s why one should avoid dietitians and Dean Ornish whenever possible.



  14. Hey Dr. Mike, great post! I think the biggest flaw of the “calorie is a calorie” mantra is thinking of the body as a perfect thermodynamic engine. People assume (or hope) that the body burns all calories equally, which we know it doesn’t. There are definite biochemical and hormonal effects of the types of calories we eat. Even the source of the calories has an effect…I think few people would question that taking 2000 calories from lettuce vs 2000 calories from chicken vs 2000 calories from Twinkies would show a marked difference in body composition. As John Berardi said regarding omega-3’s, “A fat isn’t even a fat, let alone a calorie a calorie.”

    Scott Kustes
    Modern Forager

    Hi Scott–

    I agree.



  15. Dr Mike,

    I’m sure you have seen this:

    It seems to provide the theoretical basis for low carb effectiveness. It addresses why a calorie is NOT a calorie.

    The paper was published in July of 2007 but I’m sure I saw an earlier version by the same authors at least a year ago, but I can’t find that link.


    Philip Thackray

    Hi Philip–

    Yep, I’ve seen the paper. The lead author, Richard Feinman, is a good friend of mine. He and I are actually contemplating collaborating on a nutritional biochemistry book that would teach the subject from the correct perspective.



  16. Given what we now know about EFA’s, and the fact that Keys group only got 30g fat/day, how much of the reaction to the starvation diet could have been from EFA deficiency?

    I don’t know precisely, but I image it had something to do with it.



  17. Are the low cal – high carb effects also a result of the quality of protein the subjects were receiving? The low fat is a BIG problem, but I’m wondering also about how important is the protein source? Why is it that the medical community is always the last to come around? Athletes, especially physique competitors (bodybuilders, etc.) have noted this (anecdotally) for a long, long time.

    Because for the most part doctors are not taught to think; they’re taught to memorize huge amounts of material and be ready to regurgitate it on tests and on rounds. I know because I used to be a doctor.



  18. I eat low carb seriously for a couple of years now. Lost 70 lbs and I know I sure eat a lot more calories than I did before low carb. Initially I lost another 30 when my old doctor told me to replace some of my carbs with veggies to lower my trigs. That’s when I started to look into low carb. I certainly know I feel better, have more energy and I haven’t been sick in about 6 years. I will get hungry though if I don’t eat every couple hours. This I’m trying to figure out as to whether its in my head (which I don’t think it is) or that I’m actually eating less calories some days. Working on the spreadsheets to figure it out.

    Regarding Colpo’s point of view. I’ve been stalled for about 6 months now. My weight fluctuations are loss and gain of muscle mainly, according to my Ironman scale. I’m read Colpo’s Great Cholesterol Con and think really highly of it. Now I’m reading his Fat Loss Bible and just read the part about the metabolic ward studies (it’s the very beginning), so I was hoping he will clarify more later. Though I would think that just because he believes, in essence, a calorie is a calorie, I believe he is using that for weight loss only. In The Great Cholesterol Con, he cites all sorts of stuff about carbs being bad for you.

    Now just need to figure out my stall.

    Good luck and keep me posted. Read Gary Taubes’ new book that’s coming out in a couple of weeks. He has much to say on the caloric issue.



  19. Sorry for commenting twice on the same post, but something is just not sitting right with me, regarding the Keys study, and especially that photo of the concentration-camp-looking young man. I find it VERY hard to believe that someone would look that way after only 6 months of an eating program that included almost 1600 cals per day, even if a huge portion were carbs. He certainly looks like he is “starving”, and I always thought that if you starved, it was protein you were lacking. The Keys diet had more protein than the Yudkin. Also, those guys in the Keys study were under lock and key, so perhaps they were also more sedentary than usual – a futher aspect that would cause them to need fewer cals to maintain.

    So I go back to my psychological speculation. Something with that particular person, at least, had to have been in serious play, don’t you think???


    Hi John–

    Yes, I think that it’s pretty obvious that there was a psychological problem with this particular guy. If it were standard behavior all of them would have chopped their fingers off. But they didn’t – he was the only one.

    The men were extremely active during the 24 week semi-starvation portion of the study. Keys wanted to replicate the conditions of a forced labor camp.



  20. Dr. Mike,

    Another highly informative and enlightening post, especially to those who advocate a high-carb, low fat diet for optimal weight lost purposes. I can certainly attest to the premise that weight loss, or rather, body fat reduction, is not simply a matter of calories in versus calories out. That is to say, i find that a low carb, high fat, moderate protein dietary approach, regardless of how abundant a calorie intake, produces no weight gain. This same protocol will also promote body fat loss,too, as well as water loss weight, at least in first few months of adoption of the diet. Then, when fat loss begins to cease, i find that it is only a matter of cutting carbs even further to occasion fat loss.

  21. Dr. Mike,

    As an addendum to my previous post, i was wondering if you could share your thoughts on the premise put forth by some individuals, such as “theBear” and to a lesser extent Dr. Greg Ellis, that substantial body fat loss is only possible in the near absence of all carbs. The Bear, for instance, advocates a total abstention from all carb-containing foods (fruit, veg, nuts, seeds, etc.). He suggests that such foods occasion more harm than good, a philosophy which i’ve come to appreciate in the more recent past.

    From your blog, i believe that you, too, believe that an “all-meat” diet is healthy for humans. Would you consider writing a post on a near zero-carb diet?

    Lastly, i practice IF regularly, in conjuction with a fat and protein rich diet. I have been toying with the idea of taking a few grams of powdered L-Glutamine a few times on an empty stomach while fasting, given the purported benefits of glutamine taken on an empty stomach, e.g. heals the GI tract, boosts brain functionining as well as testosteron and growth hormone. Also, first thing in the morning, i am considering taking a bit of tyrosine.
    Since glutamine and tyrosine don’t contain calories, so to speak, i assume that these supplements would not preclude the benefits of IF. What do you think?

    Hi Andy–

    If you look at the bottom picture of the guy in the Keys study, you can come to your own conclusions as to whether someone can lose substantial body fat on a high carb diet. These guys lost a lot of body fat on high-carb diets. It’s obviously not the best way to do it from a health perspective, but it does work if the calories are kept low.

    I am indeed considering a post on a near zero-carb diet.

    No, despite the fact that the glutamine and tyrosine contain a few calories, I wouldn’t worry about taking them on fasting days.



  22. What an eye-opening article! The photos told the story. I just wish that the other study had before and after photos as well. It would have been interesting to compare them.











  24. Thanks again and again Dr Eades for your incisive analysis. The item I found particularly disturbing was that so many people on the high carb diet developed psychological issues. Those who know these facts and continue to support a high carb intake do great evil.

    I agree.

  25. I was surprised to read thru the Stock and Yudkin pdf and see “the low carbohydrate diet”, the constant referral to protein/fat/carbohydrate ratios, and the criticism “Low carbohydrate diets are unavoidably high in both protein and saturated fats.”, etc., because you had written that this was an old study. So I double-checked the beginning of the article:

    Vol 23, No. 7, July, 1970…”

    1970?! In 37 years we’ve added nothing but trans-fats to the conversation.

    Yep. Sad, isn’t it. Gary Taubes’ new book will tell you why.



  26. ref the Minesota study..canny be arsed to afix spelling; tardy youth that iam

    ref the por fella who chooped off some fingers………Funny remembrance springs to mind about an old Buddhist monk acquaintance who would dream about eating his fingers..i always wondered if it was cos he was protein deficient.

    Well being kept on such a diet for so long says surely only one thing to the body… you’re dying.
    And the fact that in evolution one would never had as many carbs as they were getting on the ‘death diet’ would surely send ones biochem into serious malfunction; too few cals i.e yr dying but also in that process the metabolic system is doing a loop de loop cos of the huge swathes of insulin.

    Oh bugger have just recalled this.
    So its 97 and have been doing a low carb thing for 2 yrs. Lot enough weight and perhaps likely was eating too few calories…my moods were all oer the place and i knew it was carb related.
    I sat on pal Andys sofa pouring oer books trying to find out what was happening explicitly and i turned the page of PP and saw ‘the nutritional vacation’ and i knew just from the title that this was likely going to be it.. and it was…. and so the next morning just had protein for breccy and of course cos of over night fast and the breccy mind, as biochem, was restored to pristine quality.

    Also have a ganders at this and all its implications vis religion etc. Blooms wonderful.
    I might have sent it to you afore but canny be sure so here it is

    Hi Simon–

    You did already send me the Bloom, which I watched and commented on.



  27. I end up arguing with people about this all the time.

    The ‘calories or calories’ argument only makes sense if one assumes that the body is basically a blind furnace and that the only purpose for eating is to dump in raw fuel. When you take into account that tremendous portions of the fat and protein we consume are not burned for energy but rather incorporated directly into our working systems in the form of membranes, tissues, enzymes, etc, it becomes obvious that the only macronutrient for which the calorie is a meaningful measure is the carbohydrate. Carbohydrates serve no purpose in the body other than burnable fuel (and limited conversion into more useful substances, i.e. fatty acids.)

    It baffles me that so many scientifically trained individuals are willing to accept a purely energetic measurement as a valid means of conceptualizing the value of foods which will largely never be used for energy–particularly in the context of the high-carbohydrate diet they recommend.

    Hi David–

    It wouldn’t baffle you if you had been around as many ‘scientifically trained individuals’ as I have.



  28. Aren’t the numbers below pretty close to what all the “experts” tell us we are supposed to eat on a low-fat “healthy” diet to lose weight and be in good health? Don’t they even recommend going down to 1200 calories and lowering the fat % even more? And we see what one poor sickly soul in the study looked like and learn that the diet drove him to self-mutilation!

    “The men in this study consumed macronutrients in the following amounts daily: protein 100 gm, fat 30 gm, and carbohydrate 225 gm. If you express these intakes as percentages, you come up with 25.5% protein, 17.2% fat and 57.3% carbohydrate. Average energy intake of the subjects in the experiment: 1570 calories per day.””

    The more I learn about nutrition, the more I think anyone urging the populace to eat a low-fat diet ought to be subject to criminal charges for malpractice.

    The numbers in the Keys study are almost precisely what most ‘experts’ recommend. Next time you go to the doctor and get the famous sheet showing the 1500 kcal weight-loss diet, just remember the ‘after’ picture in this post. If you should try the 1200 kcal version, you could get there even faster.

    But before you launch off on the program, remember, these guys couldn’t have stayed on the diet had they not been locked up.



  29. My simple take on the calorie issue is [and since I don’t really know what I’m talking about I could be wrong but …] – yes, a calorie is a calorie is a calorie because a calorie is a just a unit of measurement. However, the nutrients they measure are different and are treated differently by the body and should therefore be expected to cause different reactions in the body. So, a unit [calorie] of carbohydrate will be used [expended or stored] by the body differently than a unit of protein. How close am I?

    You are pretty close. Protein and carbs – although they both contain about the same energy gram for gram – are handled differently by the body.



  30. Nice post. I’m going to get that book.

    My husband and I were discussing this very thing the other day–doesn’t it actually take more calories to convert protein and fat to usable energy (glucose) than it does carbohydrates which hit the blood stream as glucose almost immediately? Wouldn’t that account for the “a calorie isn’t a calorie” experience most people have on low carb diets?

    It would certainly account for a part of it.

  31. Hello Dr. Eades,

    One of these days, along with all the posts you are writing and the ones you plan to write, could you address the issue of cycling carbohydrates while on a very low carb diet to boost leptin and fat loss?…

    This is a technique used by natural bodybuilders which many people swear by… I myself use it, I keep most of my days with 0 to 10 g carbs and then some days (once a week) have a bunch of carbs… it keeps me from plateuing (I know I mispelled that!)

    Was curious to get your opinion and thoughts on it…

    You are the best – Jay

    Hi Jay–

    Thanks for the kind words. Carb cycling is on my ever-growing list of future posts.



  32. IMHO, it seems the Calorie-is-a-Calorie people who constantly quote the 1st law of Thermodynamics (Energy/matter is always conserved) forget two things:

    The second Law of Thermodynamics (Entropy always increases): i.e. effective energy is always lost in a process to heat, entropy, etc. based on the process in question. Different calorie sources are processed by your body differently, resulting in differences in conversion from potential calories to the energy your body actually uses and/or stores as fat. As I understand it, protein’s conversion to energy is the least efficient of the macro nutrients (I might be wrong, though.)

    Also, not all macro nutrient sources are used exclusively for energy. Fat and Protein are often used as ‘building materials’ for cells in your body (Especially if you’re combining strength training with diet, tearing down and re-building muscle tissue rapidly, stressing and strengthening bones, etc). Fiber isn’t used for energy in your body, but I don’t know if it serves any other purpose, and most other carbs are only used for energy (Again, I might be wrong on this). Revisiting the 1st law of Thermodynamics again, the fat/protein that’s used as cell building material should ALSO be subtracted from the calories your body uses or stores in fat cells.

    At least, those SEEM to be the major factors. I’m not sure if they’ve ever been quantified or tested yet. Anything other factors being left out?

    Hi Bob–

    Yep, there is another factor that’s being left out. Especially by the people who resort to the laws of thermodynamics to explain weight loss. The laws of thermodynamics apply to a CLOSED system – the human body is anything but.



  33. Dr. Mike,

    While I believe in the essential truth of your post that the type of calories is important in how people feel when in a calorie deficit regime, and while you stated that you know that you’re not truly comparing apples to apples with these studies, I do think it is important that you state for your readers what some of these differences are in these studies so that people do not put unmerited reliance on the conclusions thus drawn from the comparison.

    At the beginning of the Keys study, the average participant was a young healthy male with an average age of 25.5 yrs, an average weight of 152.7 lbs, an average height of 5’10”, and an average body fat of 14%. (pgs 68 & 83)

    The Yudkin participants were attending a weight loss clinic and so presumeable had a higher body fat content. They were probably older (age range from 21 to 51 yrs) and hence metabolically less active.

    In the Keys study the participants were required to walk 22 miles per week outdoors in Minneapolis, Minn. They in addition walked 2 to 3 miles/day going to the dining area, plus did various physical fitness tests over the course of study. This amount to about 40 miles/week of walking. The starvation period of the study started Feb. 12 which would be a cold time to be walking outdoors in Minneapolis.

    How much activity the Yudkin people got is not stated but I would guess that it would be significantly less.

    Whenever one has less body fat and is more metabolically and physically active then the hunger becomes more intense for any diet.

    When doing a complete water fast, once ketosis is established, the body is consuming an almost 100 % fat diet from the stored body fat and hunger completely disappears, but when the body fat in the fast is nearly exhausted then hunger comes back with a terrible urgency.


    Hi Porter–

    Looks like you’ve done my job for me. You’ve laid out all the specifics I didn’t. But I still draw the same conclusions from the study.




  34. Howdy Dr. Eades,

    My wife reads your blog regularly and brought this post to my attention.

    Interesting findings, though I think comparing a 36-week study to a 2-week study is less than ideal (assuming I read that correctly). Very different results may have been obtained if the low-fat study lasted only 2 weeks and the low-carb 36.

    The science behind low-carb is compelling — even to a humanist like myself — but this example might not convince any skeptics.

    Hi MGJ–

    Actually the semi-starvation part of the study lasted 24 weeks, not 36, so it was a 24 weeks study verses a 2 week study. As I wrote in the post, it wasn’t really comparing apples to apples for this and other reasons. I compared them to simply show that people had to be kept under lock and key to be able to stay on a 1500 kcal/day diet whereas those subjects who restricted carbs but were allowed to eat unlimited amounts of everything else spontaneously dropped their intake to a little over 1500 kcal/day. Comparing these two groups would never fly in a scientific journal, but I posted on them because I found it interesting. And, I have read most – if not all – of the scientific papers on low-carb dieting, and they all – even the ones lasting a year – show that subjects switching to a low-carb diet spontaneously drop their caloric intake, so the Yudkin study is right on the money.



  35. As somebody trained as a mechanical engineer, I always thought that this “a calorie is a calorie is a calorie” used by health professionals is a good example of how a good concept in one discipline can be misunderstood by people in another discipline.

    If you take a reciprocating engine in an automobile, a machine much simpler than a warm-bodied animal, it *does* make a difference in efficiency what kind of calorie it burns.

    For instance, a high-octane gasoline is more efficient than a low-octane gasoline with the same amount of calories per gallon. The reason is that the engine can use a higher compression ratio and can be more efficient, there’s no magic there. That’s why airplanes – where weight is paramount – use high octane gasoline, something usually achieved with poisonous lead-based additives. Diesel engines are much more efficient than justified by its slightly larger caloric contents. OTOH, if you use a cheap petrol-based rubber solvent instead of gasoline – as sold by some crooked gas stations in Brazil – efficiency goes down big time.

    There are many other variables that affect the efficiency of a given kind of engine as well, such as external temperature, the time it takes for the engine to warm up, the kind of load the engine is driving, if the rpm vary or is it the same and so on.

    So even for something as simple as a reciprocating engine, a calorie is *NOT* a calorie. It is ludicrous that the same concept is taken as gospel for biology.

    Hi Mauro–

    Thanks for the interesting comment, which makes perfect sense.



  36. Si i take it from Yukins study that most of el fatty was saturated ?

    I notice that even within the sat realm one has cravings for partic types of sat fat that might be termed’ more evol correct, in their animal origin, than others.
    Par example i like co-cunny oil but if there’s ghee around i will always take the ghee over the coconutty

    You and I both. I would prefer ghee to coconutty myself.



  37. There is nowhere near 50 grams protein in supper no# 2 – more like 20 grams protein by calories

    If this meal is served twice daily – thats 40 grams protein – a starvation amount

    It also appears Sam is already missing his left fingers in the before photo – can’t tell for sure –

    I suppose next your going to tell me – well super no 2 in this instance only had 20 grams protein – when it usually had 50 grams protein – or they got 80 protein grams for lunch

    Ya – and I have some swamp in Florida I’d like to sell ya –

    Of course a person would tend to waste away on 40 grams protein a day –

    Hi Jeff–

    I included the menu for Supper #2 because that was the only specific meal presented in the book. And, according to the author, who interviewed all of the subjects still living, that was the favorite meal. The fact that it is #2 implies that there are a number of other meals. With the time and attention Keys put into this study – which, BTW, could never be repeated today for ethical reasons – I’m sure there was 100 g protein per day.

    And, also, many people get fewer than 40 g of protein per day over the long term and they don’t waste away. As long as the carb intake is up, protein is spared.



  38. It might even have been on this blog, but I read of an experiment where two sets of lab rats were put on separate diets, one low-fat, the other low-carb. The low-carb rats thrived.

    The low-fat ones looked ok the morning of day one, and looked ok the morning of day 2. But on the morning of day 3 the bigger rats had eaten the heads of the smaller rats during the previous night.

    Same thing happened when the experiment was repeated.

    The guy was probably lucky he only lost a few fingers!

    Probably so. I guess he ran the risk of being eaten by the other participants.



  39. Interesting comparison Mike between the two diets, and one that is difficult to get people to understand – for some god forsaken reason.

    Colpo is a jerk BTW.

    The one problem I see is that different size people require different amount of calories. How big was Sam Legg? 5’9″ or 6’5″? 1570 cals might be fine for me even with the Keys macronutrient content at 5’10” but too low and thus all wrong for you Mike at 6’2″. So this factors in to some degree.

    Having said that (and I HATE to say this) but I do find it very curious that some people seem to thrive on high carbohydrate diets that consist primarily of non-refined carbs. The lawyer/bodybuilder Clarence Bass of ‘Ripped’ fame being one of the many. This is why I am so very interested in your take on Metabolic Typing which states that some people will do very poorly on a PP diet and actually get sick. I do not believe this for a second, but the concept is gaining wide acceptance. Dr. Joeseph Mercola is a staunch advocate of MT.

    Too bad there were no comparison photos from the Yudkin study!

    Hi Fred–

    The subjects in the Keys study had an average height of 5′ 10″ and an average weight of about 153 pounds.

    Can’t speak to the personality of Anthony Colpo because I don’t know him, and, in fact, know very little about him. I would be curious to hear your story.

    There is no question that some people can do well on high-carb diets because some do. The question is: would they do better on a low-carb diet?

    I’ve gotten your emails on Metabolic Typing, which, BTW, I believe is hogwash. But I haven’t read the stuff you’ve sent yet because I have been covered up with other projects all of which I’m behind on. I’ve got to do some traveling next week, so I’ll take them along and read them while I’ve got some down time. And report on them. Maybe I’ll find that they’re not hogwash, but I’ll be surprised if I do.



  40. Like John from a previous comment I’ve been running an IF / LC diet for the last five weeks and loving it. Food aversion is something I used to dream about, today it’s almost a problem. I hadn’t thought about it until now – why would I feel deprived eating bacon and butter and using cream in my coffee instead of LF milk?

    Thanks for the information on the Yudkin Study, while I’ve read up on the Keys research this is the first I’ve heard of the former.

    As always, informative and a pleasure.

    John Yudkin, M.D., Ph.D. was (he died in 1995 I think) a long-time low-carb advocate and researcher who published hundreds of papers and numerous books. He’s one of my heroes. In fact, we dedicated Protein Power to him. Dr. Yudkin figures prominently in Gary Taubes’ new book where you will learn much about him.



  41. I used to do pretty well on a high-carb diet. Then I turned twenty.

    A lot of people have developed that problem. It happened to me when I turned thirty.



  42. What did the Keys subjects do all day? 24 weeks of lounging around, or could they do some sort of activity. I love a week off work being idle, but 24!!! the mind boggles


    Hi Neil–

    No. They worked their butts off. Keys wanted to replicate the circumstances of forced labor camps, so he made sure they ran or worked almost to exhaustion.


  43. If you aren’t tired of engineering comparisons, I think there is a good one in control systems theory. In a control system, there is feedback, meaning the system effects the input, but the input also affects the system. The “calorie is a calorie” people are assuming the the system is fixed and not affected by the input. That isn’t true of most systems, and certainly not the human body.

    Just to take one obvious example: people’s metabolisms are affected by what they eat.

    An excellent example. Thanks for sending it along.



  44. [QUOTE]The lead author, Richard Feinman, is a good friend of mine. He and I are actually contemplating collaborating on a nutritional biochemistry book that would teach the subject from the correct perspective.[/QUOTE] Can I be the first to put my name on the list to get a copy?? You need a new book to add to your great PP series.

    I’ve got your name on the list. It will probably be a while in the coming, though. Richard and I are just in the contemplation phase.



  45. “With the time and attention Keys put into this study – which, BTW, could never be repeated today for ethical reasons – I’m sure there was 100 g protein per day.”

    I disagree – this study is being conducted every day, without any informed consent, every time a doc in the US or UK hands out one of those nasty 1500 Calorie, LF/HC diet sheets. If it were unethical, why are they allowed to get away with this? (Iknow, I’m just being sarcastic.)

    You’re right. We have all been the subjects of a giant experiment, the hypothesis of which is that low-fat diets are good for us. The outcome of this experiment: Adult obesity has skyrocketed, childhood obesity has almost tripled, and type II diabetes is at epidemic levels. And what’s the answer to all this from the majority of ‘experts’? Cut the fat even more.

    It defies belief.



  46. I am astounded that no one has commented on this relating to the Keys study. This was a completely unethical study which should never have been permitted in the first place! At the first sign of distress, the study should have been ended. Ancel Keys seems to have been an amoral (and unethical) person). There is and was no need to “study” the effects of starvation as we know the end result……

    As far as I am concerned, I will ignore any supposed studies by Ancel Keys!!!

    Judy B

    You’ll ignore them even more when you read Gary Taubes’ book. Ancel Keys is the person who virtually single-handedly got us into the low-fat mess we’re in. As Taubes said of him: He wasn’t really a very good scientist.



  47. After reading about the poor man who was so distressed he cut off his own fingers, I wondered if the low fat, high carb mania is partially responsible for many people being depressed/bipolar/in therapy for life.

    It would certainly explain why I personally feel so much better eating a low carb diet. As soon as I stopped worrying about how much fat I was eating, I started feeling better and better!

    It’s probably no coincidence that at about the same time the bookshelves in bookstores across the country were sagging under the load of low-fat diet and cookbooks, that they were also sagging under the load of all the books on depression. And sales of anti-depressants were at an all-time high.



  48. I am a 68 year old woman with Type 2 diabetes. I have known for at least 30 years (before I knew I was diabetic) that we are what we eat, and that high carbs were the basis of my then weight problems. Basically, thanks to Robert Atkins.

    It is so hard for me now to find most people so incredibly stubborn in accepting the facts! The information is there; why can’t people see it? Why can’t they give it a try and find out how they feel?

    Looking back, I can see that I just accepted feeling mediocre most of the time. Attributing that to age, family problems, menopause, whatever! No doubt these are all valid problems, but eating high protein and fat, and low carb, can be such a help!

    The older I get, the more intense my response to diet seems. If I deviate much, by eating wheat products, or potatoes (my downfall) I feel almost like I have a hangover the next day. And for a large part of my life, I just accepted this as normal.

    Something I think has helped me a lot is not trying to find substitutes for things. You can spend your life reading packaging on various products, when it’s SO much easier to just go back to the very simple (and delicious) basics. Don’t try to find sugar substitutes, or low carb pasta. Change your thinking to do away with pasta and sugar.

    Of course, I believe that there are individual variations in food tolerences and preferences. We are not all exactly the same. But I think we are trained away from listening to our real biological needs, which SHOULD dictate what we eat. What if lions got tired if eating zebras and wildebeast? What if they demanded oatmeal and cornbread and baked beans? Well, actually, it makes no more sense than what human beings eat today!

    I was VERY interested in this latest study, because it sort of goes beyond what I’ve seen before- it is really quite extreme. The suggestion being, of course, that a diet high in carbs, even with “acceptible” protein amounts, results in dysnutritrion. Are there any similar stuidies being done today?

    And a final, personal question for you- are you currently (or is your wife) in medical practice? It seems to me that you two are traveling most of the time; do you still accept patients?

    Hi Dorothy–

    I think you are right on the money with this comment. It drives me nuts when people on low-carb diets try to recreate their high-carb diets and keep them low-carb. It isn’t too bad to eat low-carb pancakes or make or buy low-carb baked goods from time to time (in fact, we wrote a book telling people how to make all these things), but if you’re going to go on a low-carb diet, go on a low-carb diet. Low-carb junk food is still junk food. Why not eat the real thing?

    At the present time neither my wife nor I are in an active medical practice. We have taken a hiatus for a few years. I don’t know if we’ll go back or not. If we do, this blog will be the place we announce it.



  49. I had a bit of a different result when I was a “Jane Brody Stepford Wife.” Before I discovered Protein Power in around 1998, I spent an entire spring and summer (about 5 months) on a very low-fat/high-carb/low-protein diet. I just plugged a typical day into FitDay, and came up with 1,087 calories with 13 grams of fat (10% of calories), 181 grams of carbs (64%), and 73 grams of protein (26%). I was also doing intense step aerobics for 1 hour a day, 5 days a week. (I’m 5’6″, and at the time weighed around 170).

    Instead of losing weight, I GAINED. It doesn’t seem possible, and I was at my wit’s end. I was very depressed. I’d already cut my eating down to nothing, and was working out strenuously almost every day. How could I cut down any further? My doctor said I needed to exercise HARD at least 1 hour every single day (he’s a jogger), and then referred me to a nutritionist (who, incidentally, looked anorexic). She told me I had to eat the same things every day. She recommended I eat even lower fat. My typical lunch was a can of water-packed white tuna with a Tbsp of fat-free Miracle Whip, a large whole-wheat bagel, and an apple. She recommended I eat a sandwich made from white bread, no butter, and a slice of baloney, and an apple.

    Thank the gods I found Protein Power!

    Hi Kathy–

    I’m glad you found it, too.

    Just think of all the other countless PBs (poor bastards) out there who are still on the low-fat treadmill wondering why they don’t get any better.



  50. mike i found I.M Healthy soy nut butter… in two tablespoons IT SAYS THERE IS ONE CARB (6 carbs, 5 fiber) have you seen this or does it make sense… also how does soy supposidly slow the thyroid do you have any comments on that?

    It probably does make sense that there is only one effective carb in a couple of tablespoons of soy nut butter. How does soy supposedly slow the thyroid?… That’s a topic for a post, not an answer to a comment. I’ll add it to my growing list.


  51. “No. They worked their butts off. Keys wanted to replicate the circumstances of forced labor camps, so he made sure they ran or worked almost to exhaustion.


    So I guess as well as having a worse diet than Prof Yudkin’s in terms of composition, their energy expenditure was large. No wonder that chap looks so emaciated.
    And as you said, another reason why you weren’t comparing apples with apples, unless Prof Yudkin was working his subjects equally hard

    cheers, neil


  52. Dr. Mike,

    The abovementioned discussion regarding high-carb diets has made me recall a book i’ve previously read which regarded carbs as the ideal fuel for humans. The book in question is Harvey Diamond’s “Fit for Life”.

    Diamond’s naive philosophy on fuel metabolism aside, one of his main tenets which has always intrigued me was his belief that fruit and it’s juices should only be consumed from morning until noon in order to facilitate detoxifaction. He suggests that fruit eaten on an empty stomach in the morning promotes the secretion of mucus from one’s intestinal tract.

    I concur with the adverse effects of mucus build-up lining the intestines, but i’m not so sure about his position on fruit. I do know from experience that eating fruit as Diamond suggests for a few days causes me to blow mucus out of my nose, but is this good? In other words, i have a feeling that the fruit might actually be causing the mucus to form in the first place. Of course, i could be wrong. If i’m not, then i may consider eating nothing but berries for the first few hours of the day when i am not intermittent fasting, followed by hearty high fat, protein rich meals.

    Your thoughts on the above issue would be very much appreciated.

    I my opinion the Diamonds are nutritional idiots. What are the Diamonds’ qualification for giving nutritional advice? If fruit causes mucus to come out of your nose, then you are allergic to that specific fruit. I can tell you that many people – myself included – eat fruit without having a buildup of nasal mucosa.



  53. Hiya Doc,

    I’m with you. I just don’t think you proved it with these studies. They ate the same calories, they lost weight. I’m suspecting that no one, given even 24 weeks and 40 miles of forced march a week, in the Yudkin would have lost as much weight as the Keys people. Calorie is not a calorie, but maybe the conclusion here is that fat keeps the fat on (and the muscle, etc).

    Anyone who wants to look like Keys’ after participant, however, should probably be institutionalized until they realize that human skeletons don’t even look good on fashion runways.

    I think the very hyped study in JAMA earlier this year proves that calories aren’t simple T-account accounting (debits vs. credits, per account). You have people, in the real world, doing Atkins, doing Ornish, doing MyPyramind and doing Zone. Atkins won (of course), and his folks ate more than the Ornish folks were, even the ones who complied.

    Last thing: I’d also be interested in an Eades-Feinman book. It’d be an interesting place to go from what you & MD have done so far.

  54. “It drives me nuts when people on low-carb diets try to recreate their high-carb diets and keep them low-carb.”

    I think the ton of false low-carb products that came out was what destroyed the epidemic of diet sanity (the low-carb “craze”) a few years back. People started cramming down phony “low” carb cereal, cookies, bread, tortillas, etc. and then wondered why they got fat and ravenous.

    Once the grain boys start throwing money at a problem, low-carb is licked.

    And I hate to say it, but I wonder if Taubes’ book will make the same splash as the NYT piece. I tend to doubt it…people will look at it and think, “Oh, that’s that idea that was discredited.”

    Americans don’t really think critically…they not only elected George Bush; they RE elected him.

    Hi John–

    I’ve read Taubes’ book three times now, and I believe it will make a major impact. Keep your fingers crossed.



  55. Hi Dr. Eades.

    Last year I went on a 900 cal/day diet. Averaged 20 ECC, 90 P, 50 F. I lost 18 lbs in 2 months, from 156 to 138. Into the third month, I developed BMS (Burning Mouth Syndrome), and olfactory hallucinations (smelled smoke). My periods became irregular, I had night sweats, hot flashes, insomnia, anxiety, and morbid thoughts constantly. I am 49 so I assumed I was going through menopause. My doctor tested hormone levels and said they were normal (huh???). I started using progesterone cream and after several months my symptoms began to subside, although I still have mild BMS and smell smoke sometimes. I have added some other supplements since that may be helping, like 5-HTP, DHEA (10 mg 5 days a wk), cod liver oil, and magnesium recently after reading PPLP.

    My “scientific”‘ conclusion from all of this is that in just 2 months eating around 50 grams of fat a day and very low calories, my hormones went completely wacko. People were starting to tell me I was too skinny, and indeed my body looked kinda ‘loose’ at that point.

    I gained all the weight back in the next 4 months or so because I was so hungry, and instead of staying relatively low carb and upping fat, I just started eating anything and everything.

    I’m back on Protein Power now and just feel so much better. Some of the ‘damage’ though may have been irreversible, like the BMS. And, I still have to use progesterone cream or the other symptoms come back. I’ve learned my lesson though – and I believe the key here is fat. Without enough and the right kinds, things just break down!!

    Your PPLP book is just the BEST – thank you for all your research and for sharing such great stuff with us in your blog.

    Hi Lisa–

    Thanks for the kind words about the book. I hope your problems ultimately clear up for you.

    Keep me posted.



  56. This is rather off-topic but you’d probably enjoy reading this article from the Telegraph (a London paper).

    Not too surprisingly, the ancient Britons were low-carb.

    The ancient Britons were low carb by default, i.e., that’s all they had to eat. And any of then who didn’t do well on low-carb fare was bred out of existence, leaving a race of people who perform best on low-carb diets.



  57. I find it interesting that I have not found a Wiki page for John Yudkin, but Ancel Keys has one:

    Protein Power and you also fail to have a Wiki page, and have a passing mention in this article:

    Despite how it is bemoaned by so many, Wiki is a widely-used resource. Colbert coined a term, wikiality, to describe this agreed upon reality (one of The Word segments, I can hunt it down if you are unfamiliar with it). Interesting how wikiality reflects reality by failing to recognize the countless years of research low-carb proponents have wasted successfully arguing the same position over and over again, and yet failing to get its due.

    Ah, that’s me. Always a bridesmaid, never a bride.

    Maybe someone should put up a Wiki page – I can’t see myself ever doing it.



  58. How do those afflicted with “a calorie is a calorie” blindness deal with gasoline, I wonder? Gasoline should make me fat if a calorie is a calorie. They must have to follow with “…if from a generally accepted food.” But then they’re arguing our point: the body differentiates between substances, a calorimeter does not.

    Sorry, idle musings.

  59. Thank you for telling me about this. I’ve been contemplating a 1500 calorie diet as a way of extending lifespan, reducing damage by reducing metabolism, but have been worried about buying more life at the sacrifice of the quality of that life. I’m glad to know that low carbohydrate/high fat dieting can give me what I want without leaving me hungry.

    Hi Lochlyn–

    Glad you found the site. Keep me posted on your progress. There is much more to life extension than merely restricting calories. One of these days I’ll do a post on the caloric restriction of rodents showing how the macronutrient that is most severely restricted in caloric restriction studies is carbohydrate.



  60. Dr. Mike,

    You have aroused the beast!!! 🙂


    Hi Andy–

    I have aroused the pipsqueak, more like.

    A while back Anthony Colpo sent me a complimentary copy of his book on cholesterol. Until then, I didn’t really know who Anthony Colpo was. I checked out his website, which I found to be filled with a lot of good information, but I was put off by the vitriol that he aimed at anyone who disagreed with him. It seemed that people would write asking reasonable questions to someone holding himself out to be an expert. Mr. Colpo would then reply to them in an unbelievably hostile way. The poor person who wrote the comment would try to say he/she was sorry for provoking the great and powerful Colpo, whereupon his response would be even more nasty. The commenter would finally get angry and give back whereupon said reader would be banned from commenting on the site. I see from his treatment of Fred Hahn and mrfreddy in the above link that his modus operandi continues. I suspect that it’s all part of his shtick, and that he uses it much as a child does pitching a tantrum to gain attention.

    Mr. Colpo reminds me of a friend of mine of whom it is said: he is often wrong, but never uncertain. I can attribute this pigheaded certainty of Mr. Colpo’s to his youth and immaturity; I would assume that as he is beaten around by life as he grows older he will be a little less certain and, I hope, a lot more tolerant. Until then, I don’t want to have anything to do with him. And I certainly won’t respond to his inane attacks on me. If he can’t understand what I was trying to say in the post in question, then it’s not up to me to be responsible for his education.

    I daresay that I have substantially more readers of this blog than does Anthony Colpo of his site and his books, and I have never felt the need to belittle or ban anyone who wrote to me asking a question or making a comment. In fact, of all the comments I have received since starting this blog, I have deleted without publishing only two. And those were two that attacked other commenters in what I felt was a hostile fashion. There is far too little civility in today’s world, and I try to do my part to contribute. I’ve always believed in civility in my personal encounters and in my online encounters and try to stay true to my beliefs. Wallowing around in the mud with Anthony Colpo would definitely not add to the world’s supply of civility, so I won’t rise to the bait.

    So, this is the last I’ll say on the Colpo situation. That is other than to point out that Ancel Keys published the Seven Countries Study, not the Six Countries Study. Once I can write off to a typo, twice to…?



  61. wow, sorry I brought him up… but I really am curious about those metabolic ward studies.

    it’s interesting how you and Loren Cordain can remain friends whilst you have publicly announced many times your opinion that he is quite wrong on saturated fats.

    Why couldn’t that, cough, cough, gentleman from down under, simply say something like “I am sorry, but I disagree with Dr. Eade’s interpretation of the available data” and leave it at that? Instead, he pumps out reams of hostility and vitriol. Oh yeah, he’s got a book to sell, right, right.

    Anyway, feel free not to comment further, or even not publish this comment, if you prefer.

    Hi mrfreddy–

    If all my friends had exactly the same opinions I do about everything, the world would be a pretty dull place. Loren and I have discussed both in person and via email our respective stands on the saturated fat issue. We’ve simply agreed to disagree. He trashed low-carb diets in the very book that I gave him a cover blurb for. Friends can disagree and still be friends.

    I often compare the medical literature to the bible. There is basically one bible and many different sects that interpret it many different ways. The vast volume of medical literature is the same. And just as one or two bible verses can’t represent the entire bible – though many sects hang their hats on those one or two verses – one or two medical studies don’t necessarily represent the truth of the medial literature.

    Certain people I know believe they are seekers of the truth, which is good. But then once they find what they believe is the truth, they become as dogmatic and doctrinaire as all the people they attack for believing differently.

    Metabolic ward studies are valuable for determining certain things. They are of less value in determining how to apply their lessons to the population at large. For the last several decades the recommendation has been to reduce calories, and where has it gotten us? We’re fatter than ever and type II diabetes is at epidemic proportions.

    Better be careful, mrfreddy, of disagreeing with me on anything or you run the risk of being banned. 🙂



  62. Ancel Keys “six countries study” is the name given to an article more properly entitled “Atherosclerosis: a new problem in public health. Journal of Mount Sinai Hospital, 1953; 20: 118-139” In this study Keys selected 6 countries and presented a correlation between fat intake and coronary mortality. Of course, if he had chosen from the other 16 countries who had comparable data at the time then no case could have been made. This was the basis for his later, slightly expanded, and more well known “Seven Countries Study.”

    Colpo, a bit of an ass, I concede, made no typo on this matter. His open letter to you can never be accused of being tactful or polite, but he does raise points regarding your work and assertions that you do not address. I was disappointed to find your reply nothing more that pop psychology condensed into an ad hominum attack. I’m also real pleased to learn that you have more readers than him. I do wonder, though, how that is relevant to anything other than a 5 year old’s pissing contest?

    First, I’m sure Colpo was referring to the Seven Countries Study, which is by far the most famous. If he were referring to the earlier study, then I apologize.

    Just because Colpo or you or anyone else raises questions about my work doesn’t mean that I have to leap through my rear end backwards to address them within the next 24 hours. I’ll do it on my schedule not on that of the very rude Mr. Colpo or yours. And I’m sure I have more readers than he (not him, ‘he’ is the correct form in this case because the verb ‘has’ is understood. I’ve noticed that both you and Anthony have a little trouble using correct grammar, something I’m usually too polite to point out, but I’ve made an exception in this case.), which probably results from the fact that I’m not a doctrinaire, dogmatic, ill-mannered twit who treats his readers as if they’re morons. And that I’ve had about 25 years of experience in the trenches taking care of patients that many others haven’t had.



  63. Excuse me, sir, but to my knowledge this is the first time that we have ever corresponded. I do not know with whom you have me confused, but it seems to me that your response is more vitriolic than my words require. Yes, I did make a grammatical error in the above post. I also misspelled hominem, though you didn’t get me on that one. I’m so glad that you made an exception to your usual “politeness” to chastise me. I hope that it made you feel better as you must be having a hard day.

    I don’t recall ever asking you to leap on any schedule. I also don’t appreciate that you left the first sentence of your reply to me (First, I’m sure Colpo…) in non-italics indicating that it was part of my post. It was not.

    You obviously missed my point about readership numbers. It does not make any difference to me how many readers you have because that has absolutely zero bearing on the quality of your information. Oprah has a much larger audience than Stephen Hawking. So? Repeatedly pointing it out just makes you look childish.

    During the time that it took you to moderate my comment Colpo added an additional (perhaps unnecessarily rude) reply on his site, basically saying the same things that I did, particularly mentioning the 6 countries study. I guess you owe him an apology, or you could just leave it at the half-hearted one from above.

    If you ever do decide to debate the issues that Colpo has raised I will be very interested in reading your reply. I might even be convinced, but if it’s just more attacks and self-aggrandizement then my opinion won’t be changed in the slightest.

    Sorry about non-italicizing the first line of my response.

    My point was that just because someone publishes an ‘open letter’ to me on his/her website doesn’t mean that I have to jump to and respond to it immediately or even ever. I don’t ever read Anthony Colpo’s website or chat room or whatever it is, and would never have even seen his ‘open letter’ to me had someone not commented on this blog and included a link for it.

    I’m sure that there are dozens of blogs out there that castigate me for one reason or another and it doesn’t really bother me. And I don’t feel compelled to defend myself to any of these attacks. I write my posts and answer my comments on those posts as my schedule allows, not as demanded by someone else who has a beef with my opinions.

    I’ve got blog posts lined out for the next couple of weeks, and, unless something arises in the medical literature that is important enough to make me veer from my schedule, I plan to publish accordingly. You and Colpo and his other sycophants (you may not be one of his sycophants, and if you’re not, then don’t take offense) may view this as my way of avoiding the issue because I don’t want to join the fray. And I don’t really care.

    I’ll get around to dealing with his incorrect (in my view) opinions in due course, but it will be on my schedule, not his. And on my website, not his.

    Readership is the currency of the blogosphere. If a blogger has something worthwhile to say and can say it coherently (in other words, provides value), then that blogger usually builds readership. If not, then he/she doesn’t. Colpo has been at it a lot longer than I and has a much smaller readership. I’ll leave it to you to figure out why.



  64. I hope you’ll not bother with Colpo. His impressive credentials notwithstanding (that darn ‘sarcasm’ key was on again!), he’s unarmed if it comes to a debate.

    I look forward to your articles. He’ll add the exclamation points and sell it as INDEPENDENT! RESEARCH! later.

    Hi seyont–

    Let’s not be too hard on Anthony. I’m not concerned that he has no credentials. Credentials don’t make one smart, they only prove that one went through some kind of formal educational regimen. I’ve met many people with credentials out the wazoo who were dumb as oxes. Smartness doesn’t come packaged in a bunch of educational merit badges. I love it that Colpo is an autodidact; I wish there were more out there. It’s usually the autodidacts who aren’t shackled by the biases of the mainstreamers who educated them.

    In certain fields, however, autodidacts, irrespective of how smart and well read they are, lack a particular dimension that can only come from experience that they can’t get because they don’t have the credentials. Law and medicine jump to mind. I’m sure that there are self-trained legal scholars out there who can recite the law chapter and verse and debate all the finer points with the best legal minds of the day. But because they aren’t really lawyers (although they know way more than most real lawyers do) they can’t practice law. And because they haven’t had the day to day experience of toiling in the vineyards of the legal system and seeing how it really works other than on a theoretical level, they’re missing what it takes to temper their theories with the reality of how things really work. It’s the same with medicine. No matter how much book smarts a person has, he/she can’t develop the sense of how those book smarts apply in taking care of real patients. One can read in the medical literature about how subjects responded to treatment provided by someone else, but there is no substitute for hands-on care of patients in being able to discern theory from reality.

    My problem with Colpo isn’t his lack of credentials; it’s his lack of manners. He is apparently unable to carry on a cordial conversation with anyone with whom he disagrees. He has a lock on the truth, and anyone who doesn’t see it his way is an idiot. I avoid those kind of people in person to person interactions and I try to avoid them in cyber interactions.



  65. Dr. E
    You need not post this comment. I am not sure that any purpose will be served to continue this topic. Yet I appreciate your comments re: Colpo. I respect his work and have bought his books.

    Many of us who read your blog are trying to figure out how to talk with our friends and our doctors about these heretical notions. You have credentials and expertise and your position is still ignored. We readers must fend for ourselves in the medical system that discounts any contribution from the great unwashed. Lives are at stake. Sometimes a revolutionary’s only tool is outrage. I try to be outraged with civility. In the long run I think doctors will be the ones most furious when they realize that they have been duped.

    Hi Marilyn–

    I have nothing against Anthony Colpo except for his lack of manners. I’m all for his (or anyone else’s) actively promoting a low-carb lifestyle. It doesn’t bother me that we have a difference of opinion on the calorie issue (although it obviously bothers him a lot); I don’t agree with anyone (including MD) on everything.



  66. ” This was the first thing I put up in the little ‘News Headlines’ section of our website today. I’ve been watching this problem develop for a long time.”

    Must confess I usually bypass the Homepage and go straight to your blog. My mistake!!!!
    Though I’ve been reading your blog for a few months, I’ve never noticed the News Section.
    Age related Macular Degeneration?? 🙂

    Hi Neil–

    I’m not as diligent as I should be putting stuff up there everyday, but I try to most of the time.



  67. Hi, Dr. Eades. I agree with your take on Anthony Colpo. I tried to correspond with him a while back, simply asking for his take on intermittent fasting. He promptly attacked and belittled me like some kind of idiot. I think he has serious mental problems and should seek immediate help for them. His extremely limited diet might be a factor in these problems.

    It’s absurd to say that a calorie is a calorie, because protein stimulates about 3-5 times more thermogenesis than carbs and 8-15 times more than fat. Most people eat low protein – about 10-15% of calories. So, increasing protein to 20-30% will clearly provide a metabolic advantage whether it replaces carbs or fat. As noted by Richard Feinman and Eugene Fine, “A calorie is a calorie” violates the second law of thermodynamics. In actuality, the thermodynamic value of each fatty acid, amino acid, and carbohydrate molecule would vary considerably.

    I found Anthony Colpo’s abusive rants to be a turn-off years ago, but he does provide quality information if you avoid his online comments that are full of hostility and vitriol.

    Hi Bruce–

    Not only does he provide quality information, he sometimes provides misinformation. Mark Twain once said: “If you don’t read the newspaper, you are uninformed. If you do read the newspaper, you are misinformed.” That’s how I feel about a lot of Colpo’s information. If some is good and some is bad, the problem becomes telling which is which.

    I’m surprised you didn’t get banned from his site or have the parts of your comments that he couldn’t explain away edited out. I’ve had people write me telling me that they commented on his site and had their comments edited by him in such a way that they looked like idiots, then he attacked them. There was no way they could really fight back because he would edit out any valid arguments they had then accuse them of being stupid.

    I’ll leave it to the mental health experts to determine whether or not he has a serious problem. If you take a look at the photo of him that is circulating around, the one where he is lifting his shirt and showing off his washboard abs, note where the light switches are on the wall behind him in relation to his shoulder height. If light switches in Australia are set at the same height they are in the US, this picture might explain a lot.



  68. Hi, Dr. Eades,

    “I’m surprised you didn’t get banned from his site or have the parts of your comments that he couldn’t explain away edited out.”

    I’ve never commented on his site, because I’ve seen how he treats people who disagree with him. I sent him a polite email years ago when he was still running the Omnivore site, asking if he’d heard of intermittent fasting. His site made no mention of it. He attacked me like a mad dog, which seems to be his modus operandi when someone brings up something he disagrees with or doesn’t know about – or if he’s in a bad mood (which is almost always).

    “I’ve had people write me telling me that they commented on his site and had their comments edited by him in such a way that they looked like idiots, then he attacked them. There was no way they could really fight back because he would edit out any valid arguments they had then accuse them of being stupid.”

    I don’t doubt this, looking at how he “debated” Cordain through a middle-man, without being in direct contact or even mentioning the word “debate.” This seems to be how he treats all people, unless they just bow down and worship at his feet. AC once attacked a guy because he wrote an unfavorable review for his book on Amazon. He wrote page after page, belittling this man (Smetannikov), rather than use his time more productively. Like you said, there is a reason Colpo never got as popular as say, Jimmy Moore, or you. He treats people like garbage unless they follow him like sycophants and has severe mental imbalances.

    “If you take a look at the photo of him that is circulating around, the one where he is lifting his shirt and showing off his washboard abs, note where the light switches are on the wall behind him in relation to his shoulder height.”

    I didn’t notice that before, but you could be right. He does have a serious axe to grind and a chip on his shoulder the size of Australia. I have talked with several people who were turned off by his presentation at the Omnivore. I already knew all the stuff he was saying, about the cholesterol and saturated fat theory being nonsense. At least he helped some people, but he cut off his nose to spite his face by removing his website content. After working for years on it, he just takes his toys and goes home because his book didn’t take off like a rocket. Maybe if he calmed down and put his content back up, the book would sell. Very few people would buy a book from some guy with a one-page internet ad and a chat group. He needs a blog or regularly updated website like Mercola and you have, IMO.

    I don’t know the reason he took down his Omnivore site – I came to it late and found it to be filled with pretty good stuff. I also liked his book The Great Cholesterol Con, but I didn’t enjoy it as much as I did the Kendrick book of the same title. I don’t have any idea why he has such a chip on his shoulder.



  69. Hi Dr. Eeades,

    “I don’t know the reason he took down his Omnivore site – I came to it late and found it to be filled with pretty good stuff. I also liked his book The Great Cholesterol Con, but I didn’t enjoy it as much as I did the Kendrick book of the same title.”

    Here is an article on Active Low-Carber with Anthony’s rant explaining why he shut down the Omnivore, basically insulting most of his readers and whining about poor book sales. As if the readers were obligated to read his book. I’ve never seen Mercola or you or anyone else post such a lame message like this. He probably alienated most of the mature readers who would have bought his book while appealing to the losers who like to see him cut people down like Howard Stern or Don Imus. Although, even they have more class than Colpo.

    I find myself agreeing with a lot of comments on Colpo in the thread. “That guy is and always was crazy.” “I like his message but he tends to be very angry and emotional at times.” “I can’t imagine that removing his website will help book sales.” He shot himself in the foot, because not every reader ran out and bought his book the first month. So, he shut down the site. It would appear to me that the poor book sales are a consequence of the kind of people that he was appealing to, his presentation, and his personality. Offending 3 out of 4 people is no way to sell books. He appealed to the lowest common denominator.

    Hi Bruce–

    Anthony didn’t sell a lot of books because there aren’t all that many people who read his site. That’s not a hack at his site on my part; it’s simply the truth. If he had sold a book to everyone on his site, he wouldn’t have sold enough books to make the writing of one worthwhile. It takes a pretty good media campaign to sell a book by an unknown author, which to the world at large, Anthony is. My first book had a large marketing campaign behind it fronted by a large mainstream publisher and I went on a 20 city book tour and the book still didn’t sell very well. The non-fiction book business is a tricky business that requires a lot of luck to make a bestseller. It took over two years before Protein Power hit the bestseller list, and that was with me (and MD) promoting it constantly.

    I agree with you that Anthony’s best bet would have been to continue with his website and let sales of the book accumulate over time. If he had hung in there until sales reached the level of about 10,000 books as did Ray Audette he could have gotten a contract from a mainstream publisher along with a handsome advance. And Ray Audette reached the 10,000 level by continuous self promotion before the days when everyone had websites.



  70. Outstanding analysis and amazing job of extracting the truth from old studies and explaining it for dummies.

    I can imagine that it can be very frustrating for you when you dig up the proof, state it simply and elegantly and wait for the idiots in power and the majority to reject and outright set aside. But please keep it up for our sake.

    Now I know why I was on a Weight watchers diet eating about 1400 calories feeling hungry all the time, miserable and weak vs. the low carb 40gram 2100 calories now that I seem to average without hunger pangs, normal BMI weight and diabetes under control. I did not believe in my dreams six months ago that this was possible.

    I guess everyone of us needs their own epiphany … direct learning not from books or hearsay but by direct experience. The tide is changing though slowing and subtly … low carb is not so weird anymore and too many success stories and too many living proofs and role models (us) out there. I think this sea change is going to happen … one person at time.. because it is true and it will prevail. Hopefully, the truth prevails fast enough before we kill ourselves as a people with obesity and diabetes.

    Hi Guru–

    Thanks for the kind words. I, too, believe things are changing slowly but surely. Too bad we’ve had to experience the obesity and diabetes epidemics before most people got a clue.



  71. I am not sure if protein has or should be connect to weather and climate conditions?
    Would you need more protein if you live in Snowy country like Sweden or in South Africa?

    Although I’m not 100 percent certain, I don’t think protein requirements are a function of the climate.

  72. I really enjoyed this piece. As always, you can be counted on to provide thoughtful concepts. As a zero-carber I’m firmly onboard being very selective in what I eat.

    But a calorie is always a calorie. It’s a measure of energy, just as a mile is always a mile and a pound is always a pound. A mile on a straight path in a suburban setting is the same as a mile through a dense tropical forest. Those two miles certainly are different, but not in distance. The same is true in human metabolism. Consuming 100 calories of sugar certainly has a profoundly different effect on your body than would 100 calories of saturated fat, but they are each 100-calories of intake nonetheless. How your body processes these inputs and their effects on your body are quite different.

    So, I hope we can get away from the question “is a calorie a calorie?” and concentrate on the nutrients and their effects on us.