Why Is Dietary Advice Stuck on Low-Fat Dairy?

It’s amazing how strong the biases about dairy foods can be. In the process of developing the 2020 dietary guidelines, it came up over and over again. Negative sentiment about dairy was one of the top themes in public comments. One bias is a visceral disdain for dairy foods in any form. Some people cannot tolerate them. Others have come to see dairy as a symbol of racism. But then there is the pervasive bias in dietary advice for low-fat dairy.

The rationalization is that dairy fat is a saturated fat. So dairy fat must be bad because saturated fat is bad. Yet a steady stream of studies tells us that, in fact, whole fat dairy products may be beneficial for health.

A New Study of Dairy Fat and Cardiovascular Disease

In PLOS Medicine, Kathy Trieu and colleagues have just published a cohort study, systematic review, and meta-analysis of dairy fat intake. One of the distinctive features of this study is that it used objective measures of biomarkers for dairy fat intake – not self-reports. Triey et al found that higher levels of dairy fat intake predicted lower risk for cardiovascular disease.

For all-cause mortality, they found no correlation, positive or negative.

Stuck on Low-Fat Dairy Advice

This is hardly the first finding to suggest that avoiding dairy fat may have no health benefits. In fact, the case is building for the possibility that dairy fat may benefit health, as Dariush Mozaffarian wrote in 2019. Reflecting on this latest evidence, Dr. Trieu explains:

“Increasing evidence suggests that the health impact of dairy foods may be more dependent on the type – such as cheese, yoghurt, milk, and butter – rather than the fat content, which has raised doubts if avoidance of dairy fats overall is beneficial for cardiovascular health.”

“Our study suggests that cutting down on dairy fat or avoiding dairy altogether might not be the best choice for heart health.”

Despite all of this, U.S. dietary guidelines seem to be stuck on low-fat dairy. The merits of it receive virtually no discussion in the Scientific Report of the 2020 Dietary Guidelines Advisory Committee. In 835 pages, low-fat dairy is a phrase that pops up over and over again. But the reason for the low-fat emphasis is barely mentioned – buried 509 pages deep in the text. It says that dietary patterns which “tended” to show less risk of mortality also tended to incorporate low-fat dairy. That’s it.

In other words, low-fat dairy is the standard advice and the powers that be are sticking with it. We wonder, though. How much longer can U.S. Dietary Guidelines will remain stuck in the face of inconvenient findings that point to a different view?

Click here for the study, then here, here, and here for further perspective. For reporting on yet another recent study with similar findings, click here.

The Milkmaid, painting by Paul Gauguin / WikiArt

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September 23, 2021