July 17, 2012


How did we come to believe saturated fat and cholesterol are bad for us?

Read Time 2 minutes

There aren’t too many topics that really get me riled up anymore.  I’m too old and too busy to care about debating the merits of stem cell research, the legalization of marijuana, or Proposition 8.  Sure, I have strong opinions on all of these topics and more, but they are just that – opinions.  Furthermore, there are enough other people out there, some reasonable, most irrational, already fighting those fights.  So what does get me riled up?  Every time I hear someone “assert” that saturated fat and dietary cholesterol lead to heart disease I have to bite my tongue.  Why do I bite my tongue?

As Frederic Bastiat once said,

“We must admit that our opponents in this argument have a marked advantage over us.  They need only a few words to set forth a half-truth; whereas, in order to show that it is a half-truth, we have to resort to long and arid dissertations.”

This is, unfortunately, quite true.  When I’m at a dinner party and someone starts lecturing the table about the perils of saturated fat (or red meat, or eggs, or fill-in-the-blank), I’m at the point – after years of being kicked under the table by my wife – of just asking the “authority” at the table one question:  Why do you believe this is true?

I figure, put the burden of proof on them, right?  This week, and I apologize for how long overdue this post is, I’m going to get into the details of  how this country (and many others who followed our lead) came to believe one of the most pervasive myths in the entire field of nutrition.

To write it all out would require a tome.  In fact, such a tome already exists.  It’s called Good Calories, Bad Calories. But for most people, especially the “authorities” who already “know” the answer, it’s a complex and lengthy book.  Furthermore, it’s not exactly something you can just whip out at a dinner party.

I recently gave a talk at the UCSD medical school.  I was asked to give a talk about “ethics.”  While I have no professional training as an ethicist, I still think I have a good idea about what is and is not ethical.  As I’ve learned more and more about this topic, it appears to me that the state of our current nutritional environment, with food policies based on just about everything but rigorous, experimental science, couldn’t make much ethical sense.  I’m pretty sure if Plato, Aristotle, and Nietzsche were still around they’d be disgusted with how we got here.  So, I was happy to take this opportunity to speak with a group of thought leaders on this important topic.

I gave a more recent (circa 2015) talk on the subject which captures both the video and and my slides, which I’ll share below. It’s about an hour long. But as Bastiat essentially said, if you want to overturn half-truths, you can’t do it with bumper stickers. Hopefully you’ll find this talk informative and useful for your dinner party discussions.

The link to this video can also be found here, for those reading this post on email or those wishing to view it in a larger format.

Photo by Irina Blok on Unsplash

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  1. I just finished it, RP claims it is one of his favorite
    Great presentation!
    Great to have the clean overview and ponder the politics of food
    You really have to watch the press with their headlines.

  2. Hi Peter,
    I am just discovering you through your website and seeing Gary Taubes on Dr. Oz a few months back (a show I never watch but the promo with Mr. Taubes intrigued me). I watched and something that I have known in my gut (literally as well as figuratively) to be true for a few years now was confirmed by Mr. Taubes. I started to follow his posts and found you.
    I am a 54 year old woman and I have always been overweight with the typical fluctuations that career dieters go through. In Sept 2009 something changed and I could actually feel the difference. It’s hard to describe but my stomach felt like it had gone from being soft and pliable to rigid and inflexible, it’s like I have a brick for a stomach now. I feel bloated all the time, my stomach hurts often and I am so tired I can barely drag myself out of bed and it’s only getting worse.
    I believe all of these problems are the result of a half century of American eating. I was raised on processed foods, high sugar, and lots of carbs. I sought medical help to find an answer and solution to my problem and my doctor; in an effort to find out what was ailing me did every test under the sun. I was told repeatedly that the tests were normal, they couldn’t find anything wrong with me. When my doctor scheduled the very last test for Gastroparesis he told me up front that if that test came back normal there was nothing more he could do for me. That was three years ago and I have been searching for an answer on my own ever since. After observing cause and effect with the things I eat I am more convinced than ever that it is the sugar and carbohydrate heavy diet of mine that is killing me.
    Something I read on your Blog really hit home “When you are overweight, it’s not because you’re eating too many calories – it’s because your fat cells are storing too much fat. These are not the same thing” I know people think I’m lying when I tell them I really do not eat a lot but I have tracked my calorie intake and I consume typically around 1500 a day. Your comment was a great encouragement to me.
    So Today I began a full hearted commitment to try to eliminate carbs and sugar in an attempt to try and feel normal again. I always feel so much better when I do this, the results are almost immediate with me but I just can’t seem to keep from falling back to old habits. Society, friends, work all seem to frustrate my efforts, either intentionally or unintentionally but either way the result is the same. I want to be healthy, what I’m doing is not living, it’s dying a slow death!
    I have subscribed to your email feed and I look forward to all the information you make available. I am embarking on what I hope will be, a transformative journey to a permanently healthier me. Any personal tips you might have for me would be very much appreciated.
    Thank you, thank you, thank you for devoting your time and efforts to this cause.

    • Sheryl, I hear your pain and I can tell you that many others do, too. I hope that resources like this and many others will continue to provide you with the support you need to make the decisions every day that will lead to you living a healthier and happier life. As you realize, this is a lifestyle change, not a diet. You’ll have good days and bad days. Over time, hopefully more of the former.

    • Sheryl,

      Good luck with your journey into the land of No Carb/Low Carb bliss. I started 18 months ago after reading Gary Taubes and continued almost six months ago after see Peter’s blog. So far I have lost 93lbs and love the way I feel now. You will never look back once you see the benefits this will bring to you.

      Try and read every single article on this site and the extremely valuable reader’s contributions. I have learnt so much from Peter and this community that has helped me in my journey.

    • Sheryl, I’m sorry for your suffering. Since Dr. Attia mentioned he hoped his blog and other resources might help you with your recovery, I thought I’d mention two other resources that have helped me. Laura Dolson, the Low Carb Diet guide at About.com has some great tips on how to make substitutes for traditional foods, and good advice on how to ease into the diet. There is a forum there where you can connect with other people following a low carb diet for support. I haven’t joined that community because I was already a member of Livestrong.com, where I have made a lot of friends, and get great support. I learned about Good Calories, Bad Calories, the Low Carb guide at About.com, and Dr. Attia’s blog from my friends on Livestrong.

      Lifestyle changes are not easy for all the reasons you mentioned, and more. Reaching out to others who share your experience can help. Best wishes for your journey back to health.

    • Hi Peter,

      I thought I’d let you know that I am on day 10 of no sugar and low carbs (no processed carbs). I have been drinking tons of water (in fact it is the only beverage I’ve had in 10 days because I realized all the drinks I loved were loaded with sugar or sugar substitutes). The first few days were a nightmare, fatigue so bad I could hardly stay awake at work, sweats, headache 24 hours a day for the first three days that I thought was going to kill me but on that 4th day I woke up feeling almost normal again, something I haven’t felt in years! Each day I’ve felt stronger and happier. I’ve emptied my house of any foods that might be a temptation and I only have healthy foods that I like (I’m not trying to expand my tastes just yet, I don’t want to get frustrated and give up). I’ve dropped snacking at night, no more cravings or hunger to try and satisfy. I take public transportation to work and the station is about a 10 minute walk from my house so I’ve started walking to and from the station as well as on my lunch hour – because I really want to now, I mean I want to get out and move!! I’ve even convinced my sister, who has Diabetes to give this a try : ) Here is a list of what I’ve observed since I’ve started this –

      No more constant bouts of dizziness
      Clearer thinking
      Swollen feeling in my entire body gone
      Hard distended stomach used to hurt when pushed now soft and no pain
      Severe stomach bloating gone
      Pain in knees gone (I can walk up and down stairs now, which I’m doing for the extra exercise)
      Stiffness when getting up from lying or sitting down gone (I used to move like a 90 year old in the morning)
      Extreme fatigue gone

      I know these results are from this new lifestyle and not from weight loss (I know I’ve lost some but not enough for results this drastic).

      I even had a co-worker tell me the other day that I looked like I was glowing 🙂
      Every time I’m tempted (which surpsingly is not often) I think of the “promise” of those poisonous foods, that good feeling, happiness (for the moment) then I think of the “reality” of those foods, dying a slow death, lack of mobility and energy and the self loathing.

      Thank you again for your mission
      and thanks Travis and Laura for the encouragement! : )

      • Sheryl, thanks so much for sharing this great story with folks. There will be struggles ahead, but you’re thinking of this the right way — it’s not just about the speed of weight loss — it’s the compete set of changes and the commitment to a lifestyle change that moves the needle.

    • Hi Peter,

      I just wanted to check in again. It’s been 38 days of no sugar, no processed foods and low carbs and I feel 10 years younger! I’ve lost 28 pounds, I have more energy, no cravings, physically, although my mind still thinks about the sweets and carbs from time to time but fortunately since my body isn’t screaming for them as well it’s easy enough to move on to other thoughts : )

      I am telling everyone about this and the whole Marketing Department where I work is going low carb! I feel like a whole new world has been opened up to me. I’m currently reading “Wheat Belly” and in a word I am stunned.

      A million thanks for your work, perseverance and dedication to educating people with the truth. Keep the information coming!!

  3. Thanks for posting this video so others can see what I had the pleasure of seeing in person. It was and is an awesome summary of a long trip down a very wrong road. I will bookmark this page and link it to anyone who continues to rail about the dangers of sat fat. I often get dismissed because I am not a doctor (though I do have an advanced degree in chemistry, which doesn’t seem to make a difference). Perhaps they’ll listen to an articulate, well spoken doctor! Perhaps.

    • One step at a time. I’m optimistic that one day NuSI will create an on-line resource second to none that will do much more than this.

  4. Dr. Attia. Thanks for presenting your fantastic lecture on your website. I found very interesting. The historical approach is very informative and helps us understand a bit how we came to where we are now.

    For years I have recommended my patients to stay away from saturated fats. This is what I learned in medical school and during my training as a cardiologist. It was always presented as a fact, the studies were never discussed.

    It was not until a few years ago that I started digging into the literature and have my own doubts. I wrote a blog myself recently on the issue in an article called “The Case Against Saturated Fat”.

    The history of the “saturated fat issue” is very interesting from a scientific and public health point of view. It teaches us how conclusions can be drawn and recommendations made from very soft data. When the wheels are turning, it can be very hard to turn back. Suddenly scientists and public health authorities have a hypothesis to defend. That´s when we tend to ignore or even not publish data that contradict our believes, and when we interpret scientific results we try to fit them into predetermined concepts. A very interesting story indeed. Hopefully we will learn from it.

    • One of the tragedies of our system is that doctors like you — who are willing to admit they were wrong, and who have the intellectual curiosity to find the truth — are not in the majority. Keep at it!

  5. This is a great talk, thank you for making it available.
    I recommend Dr. Lustig’s sugar lecture, and Dr. Taubes’ “Why we get fat” lecture to my low-carb-hater friends. Now there are three videos I can have people watch before continuing to argue with them about my diet.

    • Wow…very cool to be in the top 3 with those other two excellent talks! Thanks. BTW – I have a link to both on my Media page for easy reference.

  6. It appears that sat fat increases LDL levels depending upon the level of carbs eaten. Any data regarding how low the carb contribution must be to avoid this. Additionally none of the studies addresses LDL-P or hyperabsorption of cholesterol.
    I would further note your stating that when some of the trials went beyond several weeks you see the low fat groups frequently increasing fat intake and the carb restricted groups increased their carb intake is indicative to me of something: neither of the diets is sustainable over a long period of time. So, while a carb restricted diet is desirable, being under 50grams per day and in ketosis is not sustainable for many.

    • To your first question, see Part IX of the cholesterol post. To your second question, it’s a fair point. I do wonder, though, if the sustainability has more to do with food “infrastructure” and a constant bombardment of bad information. However, the first-order question should be about mechanism of action. Once we understand that, by all means we should have the discussion about how to implement it.

    • Actually to contrary I find nutritional ketosis fairly easy to sustain. My experience is that I went on a really unstructured and uninformed low-carb diet and lost lots of weight but it I found it became much easier when I recognized the role of increasing fat and not getting stuck on protein keeping protein levels high. I am grateful for the advice about how to make the choice of which type of fats (stress saturated and monounsaturated and avoid PUFA’s except for omega-3’s) optimally healthy. Eating foods with fat content is wonderfully satisfying and enjoyable. I think nutritional ketosis is pretty easy, and I find myself just as fit even though I exercise less (not a deliberate choice, but I find how much longer my fitness level sustains itself very intriguing).

  7. I’m curious if you saw this article in today’s Wall Street Journal: https://online.wsj.com/article/SB10001424052702303612804577531092453590070.html?mod=WSJ_hps_MIDDLENexttoWhatsNewsFifth. It’s interesting to me that some are focusing on fighting inflammation now as a justification for a low-fat diet (although part of the diet she says is recommended is actually low-carb, butter and red meat are still considered bad guys). I seem to recall that the recent Ludwig trial found that there was a slight tendency for a low-carb diet to increase c-reactive protein, and, thus, possibly inflammation. Could this be the low-fat camp’s next justification for sticking with their theory or am I reading too much into that? Also, what is your opinion on the c-reactive protein increase that was found in that study? Thanks for your work.

  8. I enjoyed that very much! Kind of like the CliffsNotes for “Good Calories, Bad Calories”.

    Arguing nutrition with people who aren’t receptive is very similar to arguing about politics…a waste of your time and energy. If you don’t have the credentials and/or the person isn’t truly interested and open to what you have to say, good luck convincing them of anything. I finally decided that I am the ultimate skeptic and if I’ve done enough to convince myself, that’s all that really matters.

    One other thought that I had, if you don’t have M.D., PhD, R.D., etc. behind your name, then the next best is possibly to just be “ripped” and then tell people that you eat bacon and butter! Might buy you some credibility.

    • If you talk to an R.D. (or even a DTR) about this stuff, pointing out that it comes from someone with an M.D. often times doesn’t even help!

  9. I read XI of cholosterol series but must have missed how low carbs need to go. Will look again. Food infrastructure maybe, but the desire for sweet tasting foods, i believe is ingrained in people Hunter-gatherers sought out fruit, and tubers. Also, many feel better with some level of starch in the diet. In my own diet the only carbs I eat (other than veggies) consist of rice, potatoes; not much mind you, but a small potato or 1/2 cup of cooked rice if i feel like it.
    Am not sure of the marginal benefit from moving from my low carb diet to sub 50grams/ ketosis.
    From an NMR- LDL-P with zero starch my LDL-P has been around 620- all large, and with some starch it has ranged from 568 to 650, but small LDL-P can be almost as half with trgs of only 50. As you have clearly pointed out, size does not matter in LDL-P so I again i am not sure of the marginal benefit to getting lower on the carb curve. Should mention I have to take a statin and zetia to get this low. Have gone zero carb, but still produce close to 2,000 particles LDL-P. I think i must produce to many smaller cholesterol poor particles. I have learned this from your work and Lecture Pad!
    Thanks for excellent, informative and most helpful work. Now in early 60’s I have time to work on health!

  10. I didn’t read through all the comments yet, and I haven’t finished watching, but I want to ask this before I forget. In Framingham they couldn’t find a correlation in the extremes of total cholesterol with intake of dietary saturated fat (which is to be expected from a biochemistry standpoint). My question is, if you look at those two groups but ask whether there is a correlation with carbohydrate intake is it found?

    • Great question. I would need to go back and look at the primary data (not just the studies). My hunch is that they did not necessarily record that info at the necessary granularity to draw much conclusion.

    • This is off the cuff, but I’ve read in more than one place about people taking these observational studies, re-running the data, and finding correlations between disease and carb intake. I think Atkins writes about it (Harvard nurses study, maybe). I think Denise Minger did the same thing with the China Study dataset.

  11. I created a 150 page website (www.healthy-eating-politics.com) as my “long and arid dissertation” to refute the lie that saturated fat and cholesterol cause heart disease, and to lay out how the money driven politics of the pharmaceutical industry, the agricultural complex, medical associations like the AHA and the ADA and the US government keep that lie alive.

    I hope and believe when enough people figure out through their own experience what constitutes truly healthy eating, we can start routing the mass brain washing. When people stop buying products produced from wheat, sugar, soybeans, corn and canola, we will be able to change the market place, and turn the tide on the staggering costs of our health care system.

    Given the damage that has been done by the diet heart hypothesis, it also infuriates me when someone lectures on how butter, meat and eggs are bad for the heart. Sometimes I’d laugh if it weren’t so ironic that this conversation usually happens at work over a table full of bagels, cookies and sandwiches.

  12. Peter, since embarking on my low carb education I’ve often wondered how so many of the key figures in the mis-education of America (with regards to Nutrition & Health) could be wrong and the data they collect shows that they are wrong. You highlight several salient examples in your talk. I just finished a book titled “Mistakes were made, but not by me” https://www.mistakesweremadebutnotbyme.com/ and I think the reasons they cite are probably at the root of the problem. They highlight – Cognative Dissonance, self serving justifications and selection bias for the positions that they hold (or cling to). When confronted with data that disproves or questions their hypothesis – they might end up going through a thought process like:

    1. I am a good man/woman and I am an expert in my field.
    2. I have recommended a diet for America that should improve health.
    3. If the diet I recommended was wrong then I have in some way shortened the lives and health of countless people.

    At this point, they hold 2 dissonant ideas and basically reject item 3 and confirm they are a good person/distinguished scientist and would never knowingly harm anyone. They continue to go all in on their hypothesis.

    The thought pattern is similar for prosecuting attorney’s who have people convicted and sent to jail only to have the case reversed with DNA evidence. They can’t wrap their head around the fact that they were wrong and took 20 yrs of someones life – so they file new charges and retry the case to prove they weren’t wrong. The diets recommened by the esteemed scientists and the good old US government have taken 20yrs off quite a few people’s lives.

    To me it’s tragic that policy was made on insufficient data and that after we now have a fair amount of data there is no “Mon Dieu” moment with people slapping their collective foreheads. Kind of like what Alec Guinness’s character says at the end of “The bridge on the river Kwai” – What have I done?

    • David, this is a great insight into a human tragedy. I wish more physicians and policy makers were aware of this “defect” in our make-up. I think we are all susceptible to this.

    • What if the LFHC diet doesn’t just take off 20 yrs, but leads to other disease, such as Alzheimers? What about those costs and suffering. I know the primary discussion is the studies to relating to CHD, but the low fat recommendations may have sent the public on the road to neurologic decline. Can you link the LF diet to other disorders of aging?

      • Great questions. There is actually an enormous body of literature linking a cluster of diseases to metabolic syndrome: CHD, Alzheimer’s disease, cancer, diabetes. In fact, it seems quite likely that removing sugars and simple carbs from diet is, in fact, an anti-aging “treatment.” Over time I will develop several blog series on each of these topics. Hope you can hang on until then.

  13. re Richie Graham- my recollection of the Ludwig study was that all diets studied reduced c-reactive protein, but the low carb diet was marginally still higher than the low GI diet- it was not clear that the difference was statistically significant.

  14. Nice lecture. Here is another vote for getting the Q&A next time! As when reading GCBC, I get really angry listening to how low fat was pushed on little or no science. We ate low fat/no fat in college/grad school in the late 80’s/90’s because we wanted to be healthy. I look back now and see certain health issues most likely stemming from this unhealthy diet. Most recently alarmed at what we had been feeding my 3 yo daughter (not enough fat) prior to discovering Gary Taubes and then this website and others early this year. Thanks again.

  15. Ok, I’m here, I’ll have a little crack at it.

    Richie, regarding the Wall St Jrl story on illness and inflammation that you asked about, I too think that inflammation is a major driver in all disease, and I think there are many things that create the inflammation and many ways to reduce it, including diet. But you have to read very, very carefully when media writers start to link ideas together in ways that may sound logical, but are not really supported by the medical literature. And you especially have to be careful with the way they interpret studies to suit their point. Actually, this doesn’t just happen in news stories, but in the literature itself. I just finished a review article published in a medical journal in which the author was examining the evidence linking dairy to diseases of civilization. Having already read all the individual studies that he was using to make his hypothesis, I felt he was making huge unfounded leaps of logic in drawing his conclusions from that evidence. But it certainly sounded like the development of a very logical idea on the surface. So you have to watch out for how the evidence is used.

    I’m only going to address two points made in the Wall St. Jrl article to illustrate this. The first is the CRP data from the Ludwig study. What really happened in the study is that all three groups saw a drop in their CRP by about half (huge drop in terms of their clinical risk). The low fat group had the biggest drop, the low carb group had the least drop, but the difference between them was only something like .02 I’m forgetting the actual numbers, but I think they were .76 and .78 respectively. These numbers were *statistically* significant in their difference, but as they are both below 1, they are completely insignificant clinically. Anything below 1 on a CRP test is totally good to go. Now compare that reality to what was conveyed in the media. I’m pretty sure it was almost universal that the media stated that CRP went UP in the low carb group. Bull. And they couldn’t even leave the lie there, every story I read on it went on further to say that because of the “increase” in CRP in the low carb group, this diet may increase the risk for heart disease (of course completely ignoring all the other risk markers that went way down, better than the other diets).

    The other point I’ll address in the article you provided was the claim that “dietary fiber from whole grains may play a protective role against inflammation”. The author doesn’t give citations for any of her claims, which makes it hard to evaluate, but on this point she refers to a “recent study”. I just googled the above phrase and found a bunch of hits on a study published in February that looked at grain fiber and risk from all causes. I’ll point out that this study was the type of study that makes some of us bristle (observational epidemiology) in which they look at food diaries in large populations (famous for being inaccurate) to draw some comparative correlations (fairly weak evidence) and then somehow by the time it’s reported to the public in the media, it becomes an all out discovery about A causing B. For an analysis of the actual data in this study though, I’ll turn it over to Denise Minger, who analyzed this study in a guest blog post on Marks Daily Apple:


    Now you see why this media stuff makes us nuts.

    • Quick FYI – the low fat was around .76 for CRP and the LCHF was about .87. All still under 1 and clinically insignificant. I think any media types who want to write about health should have to pass some sort of test (similar to a drivers test) to show they know the difference between correlaton, causation and a controller experiment vs. a epidemiological survey. If they can’t pass the test, then they shouldn’t be allowed to write about it. Thanks for your observations. Then again I also think you should have to pass a test to be able to play on a golf course when it’s crowded.

  16. Richie,

    The low carb diet did not lead to an increase in CRP. That was the whole point of Peter’s previous article:

    “Each group experienced a significant decline in both PAI-1 and CRP, and there was no significant difference between the groups for either marker. However, the trend was (barely) significant favoring the low carbohydrate group for PAI-1 and favoring the low GI group for CRP.”

  17. Peter: I was glued to my computer during your presentation and liked the way you laid out the facts.
    In several of the studies you showed, the different groups would make initial progress on their prescribed diet only to lose some of the gains the longer the study went on. More than once, you attributed it to the fact that there was reduced adherence that diet. Could something else be going on?
    I have found at times when I experiment with a new diet the same thing happens, and I know my adherence is just as strict. I wonder if our bodies have some mechanism to maintain the status quo. I am not scientist and can’t begin the guess what is going, but I question whether adherence is the total answer.,

    • It’s a fair point, and both forces may be at play. However, when you look at intake (e.g., in the A TO Z trial), you see what is commonly observed between 2 and 12 months.

  18. Thanks for your comment about having to knowingly answer questions wrongly on your nutrition CMEs. I had to show that to my 9-year-old twin boys, who pronounced you “cool”. One evening at dinner several months ago, they informed me of a TASA test question about limiting saturated fat to reduce heart disease. Funny thing is they knew how to answer it, wrongly, to get it right.

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