Saturated fats and heart disease

If saturated fats caused heart disease, then people who eat more saturated fats should be at a greater risk... but they aren't.

Review articles of prospective observational studies don't see any associations. One study published in 2010 that looked at 21 studies with a total of 347.747 individuals concluded (56):

"A meta-analysis of prospective epidemiologic studies showed that there is no significant evidence for concluding that dietary saturated fat is associated with an increased risk of CHD or CVD."

Other reviews of the evidence lead to the same conclusion. There is no link between consumption of saturated fat and the risk of cardiovascular disease (57, 58).

But observational studies can't really prove anything, they can only demonstrate correlation. So we can't exonerate saturated fat based on such studies alone.

Evidence From Randomized Controlled Trials

Fortunately, we do also have randomized controlled trials. Such studies are considered the "gold standard" of research.

The Women's Health Iniative is the largest randomized controlled trial on diet in history. In this study, 48.835 postmenopausal women were randomized into a low-fat diet group and a control group who continued to eat the standard western diet.

After a period of 8.1 years, there was no difference in the rate of cardiovascular disease between the two groups (59). The diet did not work for weight loss, breast cancer or colorectal cancer either (60, 61, 62).

Another massive study, the Multiple Risk Factor Intervention Trial (MRFIT) involved 12.866 men at a high risk of heart disease. This is the group of people most likely to see a benefit if the low-fat diet actually worked.

However, after 7 years, there was no difference between the men randomized to a low-fat diet and the group eating the standard western diet, despite the fact that more men in the low-fat group also quit smoking (63).

The low-fat diet got tested, it didn't work. Period.

Overall, there is zero evidence that saturated fat causes heart disease, or that reducing saturated fat leads to a reduction.

Just for fun, I'd also like to show you this graph of how the obesity epidemic started at the exact same time the low-fat dietary guidelines were released to the American public:

Obesity is a major risk factor for heart disease, diabetes and other chronic diseases.

Of course, this graph only shows a correlation and doesn't prove that the low-fat guidelines caused the obesity epidemic, but it's still an interesting observation.

Despite having been repeatedly proven to be ineffective, mainstream health authorities and many nutrition professionals still continue to peddle the low-fat diet.

BOTTOM LINE:There is no evidence that saturated fat increases the risk of heart disease, or that diets low in saturated fat reduce the risk.

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