Mangled Messages about Saturated Fats
Depending on what you read, you might be firm in your faith that replacing saturated fats with polyunsaturated fats is a good strategy for reducing the risk of cardiovascular disease. Or your might wonder about sensational ideas advanced by health reporters like Sandy Hingston and Nina Teicholz.
Hingston says “USDA screwed up the American diet – and deprived me of so much delicious butter.” Teicholz ginned up a best seller (The Big Fat Surprise) with her claim that “more, not less, dietary fat — including saturated fat — is what leads to better health, wellness, and fitness.”
At FNCE yesterday, Alice Lichtenstein and Carol Kirkpatrick very carefully explained that the science of the cardiovascular risk presented by saturated fats has not really changed. What has changed is the understanding that the recommendations to consume less saturated fat can have unintended consequences. Those consequences come from the food that replaces the fat. Lichtenstein summarized:
Replacing saturated fat with polyunsaturated fat appears to be a useful strategy.
But somewhere along the line, the message shifted to low fat, which was not such a good idea because of the increase in refined carbohydrates that followed.
So Teicholz is half right when she finds fault with low fat recommendations that most everyone has already abandoned. But her sensational claims about saturated fat don’t really hold up to careful scrutiny.
What does hold up well is an overall healthy pattern of eating that includes healthful fats. The idea is that whole diets matter more than individual nutrients in isolation. The Mediterranean diet is an obvious example of a healthy dietary pattern backed by good evidence.
Teicholz disputes the idea that her claims are sensational. She told ConscienHealth:
Indeed, over the past five years, there have been some 17 meta-analyses and systematic reviews finding that saturated fats have no effect on cardiovascular mortality and no association with heart disease. These findings have been largely ignored or dismissed by nutrition experts, perhaps because they remain attached to their theory that these fats cause disease.
However, the meta-analyses Teicholz references did not consistently distinguish between replacing saturated fats with unsaturated fats and replacing them with carbs. The results are different. Replacing saturated fats with carbs is unhelpful. Replacing them with unsaturated fats is beneficial.
Nutrition science often leaves room for debate. The debate is more meaningful when guided by facts.
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October 19, 2016