Before processed foods, people rarely got heart attacks—even when they ate lots of animal fat.

Historical human populations consuming diets high in saturated fat from animal sources likely had higher circulating LDL cholesterol levels than contemporary populations, yet exhibited negligible rates of atherosclerotic cardiovascular disease.

The emergence of atherosclerotic cardiovascular disease as a leading cause of death occurred only in the 20th century, despite consistent human consumption of animal-based diets throughout evolutionary history.

The introduction of industrial seed oils into the American food supply coincided temporally with the emergence and exponential rise in recorded cases of cardiovascular disease and metabolic disorders.

Pre-20th century human populations exhibited prevalence rates of cardiovascular disease, obesity, and type 2 diabetes below 1–5%, coinciding with minimal consumption of industrially processed seed oils.