Fat’s not gonna kill you

Since the 1970s, Americans have been blasted with the “fat is lethal” mantra from doctors, nutrition experts, bureaucrats, Congressmen and the nosy old blue-haired lady at the grocery store. Finally, this nonsense might be coming to an end.

I won’t go into the long legacy of the fat=death kerfuffle (Gary Taubes does it well in the first section of his book Good Calories, Bad Calories). Needless to say, it’s messy and confusing and not scientific at all.

Recently, the Annals of Nutrition published the findings of an analysis of several relevant studies on the association between coronary heart disease (CHD) and fat intake. You can read the full report here, but here are a few highlights.

Intake of total fat was not significantly associated with CHD mortality [page 3 of 29]

Intake of TFA [trans fat] was strongly associated with CHD mortality [page 9 of 29]

Intake of SFA was not significantly associated with CHD mortality [page 9 of 29]

Intake of MUFA [monounsaturated fats] was not significantly associated with CHD mortality [page 9 of 29]

A 5% incremental increase in PUFA [polyunsaturated fats] intake was associated with a significantly lower risk of CHD events, but not with CHD mortality [page 9 of 29]

the lowfat diets did not affect CHD events [page 16 of 29]

Transfat is going to kill you. Polyunsaturated fats are going to save your heart. Later, in the discussion section

There is probably no direct relation between total fat intake and risk of CHD. The strongest evidence in support of this judgement comes from the Women’s Health Initiative that showed that CHD risk was not reduced after 8 years of a low-fat diet. The observational evidence, summarised in the meta-analysis, showed no association between total fat intake and CHD risk, although there was heterogeneity between the study results…

Clinical trials of fat-modified diets, in particular lowfat or high P/S diets, and coronary disease are rarely single factor interventions. Substitution of 1 type of fat for another or reducing total fat intake, invariably results in a range of food substitutions such that intake of other macro- and micronutrients is altered.

There’s a whole lot more in there that I could quote. It’s an amazing review that discusses one of the most life-altering mysteries of the 20th century. Dietary fat has been blamed for the ills of our time-from obesity to diabetes to depression-yet no study, to date, has provided a solid, causal relationship.The majority of studies supporting the dietary fat/ heart disease link, as this analysis states, involve confounding factors.

What these studies do succeed at, though, is the induction of the healthy patient syndrome. Just as the flu shot prevents 50% of deaths from all causes, study participants are so immersed in a culture of recording food that they naturally gravitate toward healthier eating. A reduction in fat may coincide with a reduction in refined sugar, high-fructose corn syrup, chemical additives, salt or any number of other potentially hazardous items. The suggestion to reduce fat intake may cause participants to seek out healthier alternatives, such as fresh fruits and vegetables. In essence, researches may be incidentally encouraging a “whole foods” diet, and the reduction heart disease recorded could, potentially, be attributed to a lower consumption of processed foods.

One of the major confounding factors involved in judging (accurately) the effects of “total dietary fat” on our health is the location of most of that fat. We’re more likely to take in the deadly fat/sugar combination through cookies, cakes and candies than take in large quantities of saturated fats from red meat. Perhaps it’s time we looked away from the fat, just for a moment, and turned our attention to our highly-refined, highly-processed food culture.