That's an empty claim without evidence.
One doesn't have to be a machine learning expert to notice the correlation between health issues and overconsumption of processed/junk foods. Traditional foods, on the contrary, are evolved, so causation is not in the base ingredients, but in processing and substitutes.
Nope. Meat is just an evolutionary adaptation which allows the human race to inhabit northern regions.
There are obviously some crosscultural differences in comsumption of meat, but there are no replicable studies that meat eaters of, say, Japan, Middle East, Greece, Georgia or Nepal are worse off than strict vegetarians of India.
This adaptation happened, perhaps, at Homo Erectus time, so, do not worry, everything is already OK.
What we never had in our long past are supplements and substitutes. One should look here.
Perhaps, before conducting studies one has to understand cooking. That overheated fat is not the same as slowly boiled fat, that pure butter has nothing in common with margarine, and no one knows what kind of shit corporations and fastfood joints are using to save costs while processing junk food.
Tribal/traditional foods tells you what is good and what is bad (and most economically efficient for given location) without any crappy studies.
There is also Chinese/Thai tradition in cooking of not overboiling foods, which, it seems, has a substantial impact on health in the long run.
And to hire a professional cook in the research team is a good idea.)