> In the blue zones, clearly the biggest factor is the diet which is almost 100% plant based.
Clearly you are extremely biased and refuse to look at things in any other way but life doesn't revolve around "I eat animals or I don't".
Vegans aren't immune to cancer or heart diseases (they only have a small reduction of these in some studies) and they don't live 20-30-40-50 years longer than omnivores. And the reason vegans weigh less is because they're more aware of how much they eat compared to the mostly uneducated (in terms of nutrition) population.