https://www.bulletproof.com/diet/healthy-eating/good-fats/
"Saturated fat got some negative press back in the 1960s, when a scientist named Ancel Keys published research that claimed it caused heart disease. You’re probably familiar with the theory — that the saturated fat in butter, red meat, and egg yolks drives up cholesterol, which builds up in the arteries, blocking the flow of blood to the heart. The study was later debunked — it turned out Keys had manipulated the research to demonize fat. Later studies showed that saturated fat doesn’t raise levels of bad cholesterol (LDL) in the body.[15][16] Yet saturated fat is still shaking off its reputation as an artery-clogger.
The fact is, saturated fat is the most stable fat that there is. A stable fat is the least likely to be damaged by oxygen (aka oxidized). Oxidized fats accelerate aging, cause inflammation in the body, and make weaker cell membranes."