A Scientific Look at Saturated Fats

— The Skeptical Cardiologist argues for the role of matrices

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A nutrition label

The Skeptical Cardiologist has been pointing out for some time that dietary advice to universally restrict consumption of saturated fats is not scientifically based.

Different foods present different types of saturated fats in different matrices and it is not reasonable to assume the overall effect of these foods can be predicted by measuring only saturated fat content.

In particular, there is not a scintilla of evidence that proves dairy fat, which contains significant amounts of saturated fat, has any harmful cardiovascular consequences. Thus, attempts to advise Americans to consume low-fat or non-fat dairy are horribly misguided.

As I wrote in my letter to the FDA and in a recent critique of the American Heart Association, "the suggestion to restrict or eliminate full-fat dairy from the diet is not a proven strategy for reducing the risk of cardiovascular disease, obesity or diabetes and should be eliminated from current dietary guidelines."

Recently, a "State-of-the-Art Review" was published in the Journal of the American College of Cardiology (JACC) by a group of prominent nutritionists that provides substantial backing for my conclusions.

I encourage a full reading of the article but here is the abstract:

"[A]cross the board recommendation to limit dietary saturated fatty acid (SFA) intake has persisted despite mounting evidence to the contrary. Most recent meta-analyses of randomized trials and observational studies found no beneficial effects of reducing SFA intake on cardiovascular disease (CVD) and total mortality, and instead found protective effects against stroke. Although SFAs increase low-density lipoprotein (LDL)-cholesterol, in most individuals, this is not due to increasing levels of small, dense LDL particles, but rather larger LDL which are much less strongly related to CVD risk. It is also apparent that the health effects of foods cannot be predicted by their content in any nutrient group, without considering the overall macronutrient distribution. Whole-fat dairy, unprocessed meat, eggs and dark chocolate are SFA-rich foods with a complex matrix that are not associated with increased risk of CVD. The totality of available evidence does not support further limiting the intake of such foods."

Hopefully, the committee discussing the next version of the Dietary Guidelines for Americans are objectively examining the extensive scientific literature that led to these conclusions.

As I wrote in a previous post on the cardiometabolic health benefits of full-fat yogurt:

"It is important to look at industry influence on research and publications (along with other biases) but it is hard to find an expert in these areas who hasn't had some industry ties. Part of these ties develop because researchers who have concluded a particular food is healthy based on their independent review of the literature will be sought after as a speaker at conferences organized by the support groups for that food."

Fortunately, my evaluations remain unsullied by any food industry ties.

Anthony Pearson, MD, is a private practice noninvasive cardiologist and medical director of echocardiography at St. Luke's Hospital in St. Louis. He blogs on nutrition, cardiac testing, quackery, and other things worthy of skepticism at The Skeptical Cardiologist, where a version of this post first appeared.