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.
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?”
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?
This article has been re-published from Larry’s blog CardioBrief as part of a licensing agreement between Everyday Health and the limbic.