–We shouldn’t forget the unintended consequences of dietary recommendations.
The American Heart Association’s position on saturated fat pretends to be science-based but is not, writes Gary Taubes, in a brilliant and wildly popular guest post published here on CardioBrief late last week. The AHA’s statement, which recommends that saturated fats be replaced with polyunsaturated fats, is based on cherry-picked and severely deficient data, Taubes writes.
With the devastating precision of a prosecuting attorney, Taubes lays out the case against the AHA paper. He doesn’t prove that saturated fat is innocent, but that’s not his goal. He does prove, beyond a reasonable doubt, that the evidence against saturated fat is inconsistent, weak, and unreliable. “If the data doesn’t exist, you must acquit,” I suppose he might say.
Here I want to focus on a different aspect of the AHA paper: its potential unintended consequences. I am afraid these may prove disastrous.
Reading the new AHA paper I was struck by its extreme self-confidence, paralleled by its unwillingness to acknowledge the disastrous consequences of the last time the AHA pushed back against dietary fat and cholesterol. The result, as we all should know by now, was to unwittingly help unleash or at least contribute to the obesity and diabetes epidemics, as saturated fat and dietary cholesterol were replaced by carbs, often refined carbs, and sugar. Notably, the AHA took a long time to change its guidelines, and when it did those efforts were far less aggressive and received far less publicity than the original campaigns.
Now the memory of that catastrophe is fading, at least in some people who would rather forget it. In an article in Medscape one nutrition expert, defending the new AHA paper, offered the following quote: “But the AHA has always taken the stance that saturated fat is bad and that we should be eating more plant oils, and this view is endorsed by the vast majority of nutritionists who are scientifically qualified. [emphasis added]” He’s already forgotten that, in fact, in its earlier campaign the AHA did not explain that saturated fat should not be replaced with carbs, or even sugar.
Confusing Public Message
The AHA message is now somewhat more nuanced than its earlier simplistic attack on saturated fats, but it’s hard to imagine how it will be interpreted by most people and applied in real life. A brief segment on CBS’s This Morning illustrates the problem. They brought in a cardiologist, Tara Narula, to explain the new paper to the TV audience. She offered no criticism of the AHA position, telling viewers that “eliminating saturated fats is similar to taking a statin.”
Then she tried to moderate her recommendation slightly, recommending to her viewers that “if you have high cholesterol you should keep saturated fat within 5-6% of total calories,” while for those without high cholesterol it’s OK for saturated fat to go to 10%.
Once again, it’s important to point out that there is no strong scientific basis to support these guidelines. This represents the opinions of the AHA and the nutrition establishment. But let’s pretend for a moment that the advice is valid. Is it really likely that anyone except the most food obsessive viewers would be likely or even able to apply these numbers to their daily life? This isn’t information designed to help most people, it’s designed to put them in their place and leave them feeling unqualified to make basic decisions about their daily lives.
“So if you see saturated fat avoid it.”
Charlie Rose, looking even more befuddled than usual, offered a simple summary that probably reflected exactly what most of his viewers had already concluded: “so if you see saturated fat avoid it?”
Coconut Oil
Much of the media coverage focused on just one small part of the AHA paper: the attack on coconut oil. Once again, the message was grossly oversimplified. “Coconut oil is not a magical health food after all” and “Health alert! Coconut Oil is as bad for you as beef fat and butter” are typical headlines. Or, as Narula told her CBS viewers, ““Take it [coconut oil] out of your kitchen and put it in your bathroom.”
Let’s take a look at what the paper actually says about coconut oil. The only evidence against coconut oil cited by the authors is that it raises LDL levels. Let’s put aside for the moment the question of whether this by itself warrants this type of action. The problem is that once again the authors cherry pick their evidence. They choose to focus on the surrogate endpoint that supports their view but dismiss another surrogate endpoint that works against their view. They bury the fact that in addition to raising LDL coconut oil also raises HDL, the so-called “good” cholesterol. They dismiss HDL because, as they correctly note, several trials have failed to demonstrate that raising HDL is beneficial. But coconut oil has never been tested for clinical endpoints, and although HDL no longer appears to play a causal role in cardiovascular disease it still appears to play an important prognostic role. It is still entirely plausible that the HDL-raising properties of coconut oil may be beneficial, outweighing the likely negative effects of the LDL increase. Their conclusion is thus entirely unwarranted: “because coconut oil increases LDL cholesterol, a cause of CVD, and has no known offsetting favorable effects, we advise against the use of coconut oil.” This may be a reasonable scientific hypothesis. It is not, by any means, a scientific fact.
Once again the AHA claims a scientific consensus that in fact doesn’t exist. The paper itself points out that more than a third of nutritionists (37%) think that coconut oil is healthy. Clearly there is a large and energetic portion of the scientific community that has taken a very different position. The AHA should not simply pretend this difference of opinion doesn’t exist.
Truth or Consequences?
Perhaps the AHA will be able to kill off the coconut oil fad, but at the same time it may have just unleashed a host of new fads relating to polyunsaturated fats. I can’t even begin to imagine what these are going to look like, but I’ll bet you’ll be seeing them soon, not only in Whole Foods but in Safeway and even McDonald’s. Let’s hope the consequences of that decision work out better this time.
The public health consequences of these messages are incalculable. The vast majority of people, even well educated people, don’t follow the science and have no interest in anything more than being told what to do. Like Charlie Rose they are looking for simple messages, and even when the message isn’t simple they will extract a simple message from what they hear. And they will not be receptive to any change in this message, since it will now be an established foundation of their received ideas. For decades now, for instance, the idea of eating fat, meat, or eggs has been the equivalent of going swimming without waiting for 30 minutes after eating lunch, or starting a forest fire. It’s what mother warned you against and so you don’t do it. This is why the anti-cholesterol campaign was so dangerous. It was astonishingly successful, permanently changing the way people thought about food. Suddenly basic cornerstones of the American diet— meat, dairy, eggs— became a bad thing.
I am not interested in defending coconut oil here. It’s a fad, and we have no idea whether or not it is beneficial. It’s always a good idea to look at fads like this with a skeptical eye. The important thing to remember is that the larger controversy over saturated fat is far from being resolved. Let’s not replace one weak piece of dietary advice for another just as weak. Why can’t we have an AHA scientific statement that acknowledges that the scientific truth in this area is elusive and inconclusive?
Related CardioBrief posts:
- Has Nutrition Science Been Poisoned?
- Top Cardiologist Blasts Nutrition Guidelines
- International Experts Call Salt Guidelines Far Too Restrictive
- More Shots Fired in ‘Sugar War’
- Lunchroom Scandal At The AHA: Day Two Of Buttergate
- Is The American Heart Association Trying To Kill Health Reporters?
- Why Guidelines Are Bad For Science
- Recipe For Disaster: The New US Dietary Guidelines
- BMJ Paper Criticizes Proposed US Dietary Guidelines
- Why Guidelines Should Be Waged Like War
- An Expert’s Perspective: Why Salt Is Not Like Tobacco And Why Guidelines Are Tricky
- Salt, Science, And The American Heart Association’s Double Standard
- An Expert’s Perspective: Why Salt Is Not Like Tobacco And Why Guidelines Are Tricky
- The American Heart Association’s Strong Stance Against Science
- How Sweet: Sugar Industry Made Fat the Villain
- New Analysis Of Old Study Delivers Another Blow To Traditional Diet Advice
- The American Heart Association’s Strong Stance Against Science
- You Say Potato, I Say Worthless Epidemiology
It AHA’s statement may have “disastrous consequences”, why wasn’t it in places like Finland, Poland, Mauritius etc.?
Isn’t Poland the place where replacing soviet sunflower oil (60% linoleic acid) with rapeseed oil (20% linoleic acid) was followed by a drop in CHD mortality – whereas the former USSR, still using sunflower oil, still has the world’s highest CHD rates?
PUFA/SFA ratio increased by 70 % in Poland between 1990-99 after subsidies for dairy and meat were cut. (according to http://www.bmj.com/content/331/7510/187)
Thanks, Eric, this more recent paper by the same team is what I am referring to. Note no correlation with animal fat.
https://www.ncbi.nlm.nih.gov/pubmed/17955332
The temporal association in the 2005 paper is suspect as a 7% drop in SFA should not immediately produce drops in CHD if SFA is causal. In this context a 57% increase in PUFA means more fat is being eaten overall (if the increase comes from rapeseed then MUFA has increased even more). Improves in blood viscosity, inflammation, and clotting due to omega-3 repletion and improvement in carbohydrate quality (fruit, and no doubt more with free trade) are other explanations.
In Karelia the Orthodox Finns had 5x the all-cause mortality of Protestants, including higher CHD https://pdfs.semanticscholar.org/1588/f59b06c93eca02edc3ea5739606ca1e6d6d2.pdf
I do not know what they ate but only Orthodox Christians have religious and cultural reasons to prefer sunflower oil to animal fat.
The dietary pattern needs to be emphasized, not individual ingredients. If other non-controversial principles are used, one need not even get into these arguments.
Increasing fiber intake a few grams daily (currently we eat 15g, and the optimum is about double that) would produce significant benefits on a population basis. Similarly, eating one medium-large fresh salad (without destroying it with add-ons) daily would do the same. Add one medium fresh fruit salad daily (without added sugar), and three portions of beans per week. This is positive dietary advice, not negative.
Another principle that has universal acceptance–eat fresh, home-made, real food. Processed food is unhealthy for many reasons, and 60% of what Americans eat is ultraprocessed.
The dietary pattern for most Americans and most humans for hundreds of thousands of years consisted of large amounts of high quality and nutrient-dense animal foods. Weston A. Price researched this in terms of fat-soluble vitamins in traditional diets. Dietary fat isn’t only about a macronutrient but also essential micronutrients.
#Bromance 🙂
Great work… Keep it coming. I share this with my Cardiologist who is not in ‘lock-step’ with the AHA or AMA..
Tropical oils good, distilled processed vegetable oils bad (margarine yuck) – follow the money – go back and look at the negative PR campaigns produced by big AG (in conjunction with US Dept of AG) back in the late 60’s and early 70’s demonizing palm and coconut oil – its all about the money. You can sell more of your home-grown oils (and concomitant sugars as HFCS) without competition.
Here are two sound; thorough, critic reviews of the work from the “brillant” Gary Taubes:
https://thescienceofnutrition.wordpress.com/tag/gary-taubes/
http://www.stephanguyenet.com/bad-sugar-or-bad-journalism-an-expert-review-of-the-case-against-sugar/
Fake quoting, unsubstantiated claims.
Claiming that all low carbohydrate diets are ineffective is a nonstarter for any reasonable arguments based on a broad reading of the science research. There are plenty of trials comparing the low carbohydrate to the low fat diets and a considerable amount of success with weight reduction by reducing carbohydrates in spite of patients often eating 10% to 15% more calories on the low carbohydrate diet. Your problem is that low carbohydrate diets are not going away with the continuing research and books written on the topic over the last 60 years. I’ve read reviews comprising 25 dietary trials all of which more or less supported the positive results of low carbohydrate diets. so the data is out there, people just have to look.
Low-carb diets, especially ketogenic (and even moreso when combined with fasting, intermittent or extended, to induce autophagy), have been proven again and again to not only help weight loss but to promote a healthy immune system, reduced inflammation, and extension of lifespan, along with much else. These kinds of diets have been successfully used to treat obesity, diabetes, heart disease, epilepsy, autoimmune disorders, mood disorders, schizophrenia, etc. The amount of research is massive and growing.
Great stuff Larry.How quickly they forget.
You might be familiar with the SMART study group and the JUPITER statin trials. Both in SMART and JUPITER (and in the older Helsinki Ezetimibe study) baseline HDL is strongly prognostic in the placebo arms, as is the TG/HDL ratio. In SMART, HDL or TG/HDL is most critical in the subgroup with high LDL-C. Although on-treatment HDL is not much of a factor, the placebo arm quartile with high HDL has just as few events as anyone on treatment. In SMART, a bit fewer..
So drugs – or genes – don’t give the whole picture. HDL, causal or not, is slap-bang on a causal pathway, which for my money is postprandial hyperinsulinaemia. The SMART and Helsinki subgroup data is linked here,
https://profgrant.com/2016/12/01/the-importance-of-the-fasting-tghdl-ratio/ and the JUPITER data at the foot of this page https://profgrant.com/2016/11/10/the-canheart-study-is-higher-hdl-better-it-depends-but-the-answer-is-yes/
I should note that this data indicates that, as the use of statins increases in the population, HDL and TG/HDL will become less predictive at a population level. But for Joe Grummit asking should I risk a statin in the first place or am I eating right and exercising enough, they will continue to be very predictive indeed. Even, or perhaps especially, when LDL is high.
https://www.ncbi.nlm.nih.gov/pubmed/22119890
This made me so hungry that I tootled off to the kitchen to have toast, butter and Philly cream cheese. In moderation, natch.
Good post, well thought out and written. You are so right when you say that the average person wants simple, easily followed nutritional advice, and when it comes from “expert” sources, it will be followed and defended.
What I see in the AHA report is also a complete lack of science to support their claims. All of the studies cited (and even all of the studies considered for inclusion in the meta-analysis) are observational. They are useful to form hypotheses which need to be tested. But even so, to form a hypothesis, one needs some science to back it up. Is there something about saturated fat that CAUSES us harm from a metabolic standpoint? Raised LDL levels is mentioned and as you say this is only a surrogate for another unproven hypothesis. For millennia humans have consumed saturated fat and thrived. Our own body synthesizes saturated fat and stores it in a majority proportion in our adipose cells. The fat content of mother’s milk contains more saturated fat than any other fat. Is nature trying to kill us? In my opinion, science is being ignored because science can’t support the flawed advice which is being given by the AHA. Saturated fat is actually very good for us. It is a stable fat and not easily oxidized. It is a very good source of energy for our body, so no wonder that we store it for future needs. There is no science which supports the contention that saturated fat is harmful. Therefore formulating a hypothesis to that effect is just plain misconduct.
About 30% of our fat stores are long chain saturated fats, while 60% is MUFA, almost all of it oleic acid The remaining 10% is PUFA (mostly linoleic acid) and medium-chain saturated fats.
The proportion of PUFA has more than doubled since the 1960s. If you want a mix of fat that resembles 1960’s body fat, a 50/50 blend of olive oil and butter should do the trick; lard also comes close. Of course we can convert one SFA to another and to oleic acid, so the mixture is adjusted internally; e.g. if we eat a lot of lauric acid from coconut oil we will have somewhat higher lauric acid in fat stores but most of it will be converted to oleic acid and the main saturated fats.
Coconut Research Library
circa. 2001
http://cri.nsf.ac.lk/bitstream/handle/1/2543/05878.PDF?sequence=1&isAllowed=y
102 References and abstracts of research and review papers written by scientists based on true scientific research results. A majority of the papers (those indicated by ‘A’) are available at the Coconut Research Institute library for consultation by those interested in the subject.
We wish the tide of misinformation on coconut oil would be soon swept up and its miraculous effects be revealed for the benefit of mankind and the coconut industry.
Here are some news about health (or death) benefits of diet
https://www.hsph.harvard.edu/news/press-releases/improving-diet-quality-over-time-linked-with-reduced-risk-premature-death/.
Some simple tips: refined carbs are the bad part of carbs and any carb can’t be considered as refined carb since whole grain are healthy. A diet that allows weight loss by eating beef and so could be a good short term diet for someone who is trying to lose weight but can’ t be deemed to be a healthy diet for every one.
In most countries there are less obese people than in the USA so the main problem is to remain healthy and not to lose weight by all means.
Modern industrially-produced “whole grains” actually aren’t whole grains. They are refined carbs that have had some fiber thrown back in. A genuine whole grain, hard to find in the modern food system, has the fiber still connected in its natural form. So, refined carbs, even in their hidden form as pseudo-whole grains, are a health detriment in all societies, whether the United States or elsewhere.
Saturated fat and dietary cholesterol are harmful, and yes, it was a mistake to replace them with sugar, but the best diet for preventing strokes and heart attacks is the Mediterranean diet, a nearly vegetarian diet high in monounsaturated fat, with a low glycemic index. This was obvious many years ago from the Seven Countries study: the coronary risk on Crete, with 40% of calories from fat (mainly olive oil) was 1/15th the coronary risk in Finland, where 38% of calories were from fat (mainly animal fat). see: https://www.theglobeandmail.com/opinion/a-diet-high-in-fat-is-best-with-the-right-kind-of-fat/article37474768/
The problem is your belief system is unsupported by the scientific evidence. No study has ever proven that saturated fat and cholesterol are linked to cardiovascular disease. In fact, as intake of saturated fat decreased over the past century obesity and heart disease increased. Saturated fat in the American diet began to go down even before the present health crisis began. It never made sense according to the data in the past and still doesn’t make sense. When Ancel Keys’ original data was re-analyzed, the stronger association to disease was sugar and not fat.