The science on why animal fat is good for humans

That's not what I'm reading; published in the British Medical Journal[1] "Drug treatment to reduce cholesterol to new target levels is now recommended [...] Achieving these cholesterol target levels did not confer any additional benefit in a systematic review of 35 randomised controlled trials. [...] The negative results of numerous cholesterol lowering randomised controlled trials call into question the validity of using low density lipoprotein cholesterol as a surrogate target for the prevention of cardiovascular disease."

Or[2] "One problem with all the trials of statins is that they look at the probability of still being alive after x years. But [...] Patients want to know how much longer they can expect to live if they take a statin every day for the rest of their lives. Is it weeks? months? years? decades? [...] In 2015, a group of researchers looked at the data from the statin trials and re-calculated the effect in terms of increased longevity. The study was published in the British Medical Journal [...] So what were the results? Life was prolonged by between -5 and 19 days in the primary prevention trials (yes, that’s -5, as in minus five. In one of the studies people taking a statin lived five days shorter than people taking a placebo). [...] When everything is averaged out, people taking a statin for primary prevention lived three days longer than people in the placebo group."

The video I linked in the previous comments talks about LDL and HDL, and argues that high cholesterol is not inherently bad, it's specifically cholesterol damaged by the presence of sugar in the blood which then means it can't be cleared out in the normal way (specific mechanism is explained) and ends up pulled into the artery walls (by macrophages IIRC), weakening them and contributing to coronary artery disease. That implies that on a standard Western diet which is high fat and high sugar you should see heart disease happen, but either on a very low carb or a very low fat diet you should see improvements (but low fat, high sugar would still give you the other problems of a high sugar diet).

> "the Hadza for example have LDL in the 70-80 mg/dl even into old age (probably because they're more active, leaner, and don't eat much saturated fat)."

Wikipedia[3] says about the Hadza: "only around 400 Hadza still survive exclusively based on the traditional means of foraging[...] A 2001 anthropological study on modern foragers found the Hadza to have an average life expectancy of 33 at birth for both men and women. Life expectancy at age 20 was 39 and the infant mortality rate was 21%.[37] More recently, Hadza adult have frequently lived into their sixties, and some have even reached their seventies or eighties"

So what is "into old age" in your comment, how many people and how old? (For comparison, life expectancy at birth in the USA and UK is >80 years and "the American Heart Association (AHA) state the average age of a person at the time of their first heart attack in the United States is 65.5 years for males and 72 years for females", so if there's only 400 of them living as foragers and it's also rare for them to reach their seventies at all, that doesn't sound much data to draw a conclusion of protection against heart disease).

[1] https://junkscience.com/wp-content/uploads/2020/08/ebm111413...

[2] https://sebastianrushworth.com/2020/11/13/how-much-do-statin...

[3] https://en.wikipedia.org/wiki/Hadza_people*

It should be obvious by now that subtle genetic differences can hold a huge influence in regards to what a "healthy" diet for someone is. IMO, there isn't enough research being done on such matters.

Anecdote. I've tested this personally and found it to be true. Gastric motility also increases with high animal fat diets, meaning on some level my body/brain feels like its getting what it requires faster.