We also didn't get vaccines for most of history. That doesn't mean remaining unvaccinated is good.

For the record, keto works for me (including bloodwork to prove it) but is unsustainable. My mind is never sufficient compared to when I'm eating normally. It's observable in my work and parenting. Although, last time I was on keto, my cholesterol was through the roof. I went off keto and three months later numbers were back to normal. And I wasn't consuming a shitton of meat and butter or anything. I was pretty close to exactly the right numbers for optimal health. Just...something made the numbers terrible and I've no idea why. Did a re-test to confirm. Same awful cholesterol.

On IF I actually got fatter. Numbers worse. Less healthy. Couldn't exercise as vigorously.

For me, calorie counting works. It's also not sustainable, because with kids you get in a rush and if you have a normal social life you eat at places you can't calorie count.

To stay healthy I just try as hard as I can and exercise (distance running, weightlifting, tennis when I can, which is pretty rare with three young children).

Why is this such a complex concept for so many? I literally cannot think of anything simpler.