I listened to few podcasts with Sinclair. When someone asks him what he eats, his reply is always "vegetables, leafy greens". No rich source of protein, fat. Is this for real?

My Dad is on a similar diet for health reasons after a cardiovascular scare (not even nuts or avocados allowed), apparently the amount of oil and protein the average sedentary person needs can be obtained from vegetables we don't tradionally think as being good sources of them because you actually don't need much oil or protein to be healthy

Though if you're trying to build muscle/are more physically active you'd probably want more protein rich food sources

Is this not just a description of a blue zone diet[0]?

[0] https://www.bluezones.com/2020/07/blue-zones-diet-food-secre...

This article mentions Ikaira. It should be noted that the diet restrictions in this region are rooted in religious fasting.

Does that change things wrt how old they tend to become or is this a heads-up about an additional dietary requirement?

Well, both, but I do think it positively impacts longevity because the fast is for a reason much deeper than extending life. The main goal of fasting is to increase the intensity of prayer, but, it has many other benefits. And then after the fast there is the feast. All of this also happens in a trusted community, no one is alone.

My point is that fasting, at least in this blue zone, isn't an end unto itself. It's just one part of a way of life, so, to focus the diet misses the whole picture.

There's no denying that Sinclair has propelled longevity research, but his promotion of certain molecular systems is generating some valid skepticism... https://www.youtube.com/watch?v=e7u6esW3qVw