> It’s also not hard to find diets high in SFA like keto and paleo and their practitioners being relatively healthy.
Keto actually looks like it might be bad for long term use based on some studies. For someone who finds that it helps them lose weight, it will still be beneficial as long as they they continue to lose weight, but it probably isn't great as a long-term lifestyle change when not losing weight.
Since most people who go on a keto diet cheat about as much as anyone on any diet (i.e. a lot), the real effect is not so much remaining in a ketogenic metablolic state for years at a time as it is cutting out some number of doughnuts, and while the original idea is extreme, the product is a result just about anybody could get behind.
It's kind of like how most religions have some insane stuff in their holy texts, but regular nice people turn it in to a positive reminder to be kind by filtering it with their human inexactness.
I find keto diet is much more satiating than low fat or "zone" type diets. I lost 80lbs this way and kept it off by doing a moderate version of it 1 meal a day of "zone" type mix and other two keto style. Obviously I eat whatever I want some days, but 90% of the time I'm good about it. My goal was always to be satiated and not to be in ketosis however. I have kept the weight for ~7 years now.
Historically, Inuit life expectancy was shorter than other populations [1]. Are we looking at what people have done or do today? Should we look at the diet of the people who live the longest and have the best health as long as possible? I'm for looking at the diets that produce the best health the longest and best vitality as we age. The Inuit people on an animal diet are not a good example of this.
Some other indigenous North American tribes also subsisted almost entirely on meat (mainly bison), and seem to have been fairly healthy. This site is pushing a particular diet so take their conclusions with some skepticism, but their underlying data seems to be mostly accurate.
The problem with these studies is that:
1) They mix in infant mortality rates.
2) Many of these "native peoples" are poorer and have less access to healthcare compared to others.
So in general it's very hard to get good data on life expectancy on these fringe groups.
Then there's a question of how much access to health care should be needed? I was recently reading about a study that found when western diets entered a region health care costs go up. I was reading about it in Barons which is a financial publication. I imagine they are looking for investment opportunities. But, the observation is interesting. I'd link it if I could find it.
If you look at the US causes of death, a high percent of them are related to lifestyle. Like so many heart disease issues being linked to smoking or arterial blockages (and they've studied the causes of those). If a group doesn't have those lifestyle components they they have better health and longevity.
The idea that the Inuit had low cardiovascular disease on a high meat, high fat diet looks to be unfounded, and based on unreliable mortality data [2]. Several Inuit bodies mummified in ice from centuries years ago have been autopsied and found to have evidence of atherosclerosis
Keto actually looks like it might be bad for long term use based on some studies. For someone who finds that it helps them lose weight, it will still be beneficial as long as they they continue to lose weight, but it probably isn't great as a long-term lifestyle change when not losing weight.