This week, the US Department of Health and Human Services announced new Dietary Guidelines that finally abandon the decades-old low-fat, high-carbohydrate dogma — a doctrine that coincided with, and arguably fueled, the explosion of obesity and chronic disease.

For someone who has followed a carnivore diet for eight years, this announcement feels surreal. I’ve spent years going down this rabbit hole, opening a Pandora’s box of nutrition science, policy failures, and institutional inertia.

What I found was not a grand conspiracy, but something more troubling: bad science hardened into dogma, then codified into policy.

In the 1950s, American physiologist Ancel Keys proposed a hypothesis that would shape nutrition policy for generations: that saturated fat raises cholesterol, which in turn causes heart disease.

To support this idea, Keys led the Seven Countries Study, an observational study that claimed to show a correlation between high-fat diets and heart disease. The study did not prove causation, yet it quickly gained enormous influence in policy circles.

What is often glossed over is that Keys largely discounted or ignored major confounding factors, including smoking rates, physical inactivity, alcohol consumption, and sugar intake. Instead of rigorously disentangling these variables, the narrative collapsed into a single, seductive conclusion: fat was bad.

Keys’ ideas fed directly into recommendations by the American Heart Association, reports by the US Senate Select Committee on Nutrition and Human Needs, and early guidance from the USDA and HHS.

By 1980, the first official Dietary Guidelines for Americans urged the public to reduce total fat, avoid saturated fat, and replace fat calories largely with carbohydrates. In practice, this meant sugar and refined starches.

In 1977, the McGovern Committee issued Dietary Goals for the United States, explicitly recommending reduced total fat, reduced saturated fat, and increased carbohydrate intake.

The report was political rather than scientific, overrode objections from many researchers, and forced consensus where none fully existed.

Food companies didn’t break the rules; they optimized them. “Low-fat” became “high-sugar.” Highly processed foods qualified as “healthy.”

Then the “heretic came.”

In the 1970s, Cornell-trained cardiologist Robert C. Atkins discovered that severe carbohydrate restriction led to rapid fat loss and reduced hunger — regardless of calorie intake.

For this, he was harshly pilloried by colleagues for advocating what was framed as a high-protein, high-fat diet.            (to be continued)