I have some thoughts about people’s reactions to studies such as this one (here’s the actual article); I see many reactions in the shape of “WE ALWAYS ATE THIS AND LOOK HOW HEALTHY WE WERE AND GRANDMA AND THE NEANDERTHALS!!” Well.
First of all, I think (and this is my humble opinion, I haven’t done the research), that in the past, people ate less animal products. Much less, like once a week? I don’t know. The doctor that was interviewed for one of the articles about l-carnitine and meat a fortnight ago said, though, that he liked meat and so he had it every other week, and that was fine as his gut microbiota stayed at low levels. Second, they were natural, bio, eco; no growth hormones, herbicides, pesticides, antibiotics (I mention the plant killers also because the animals eat stuff too, which becomes them). Third, we’ve become idle. Most of us are not moving. We’re not helping our bodies. Fourth, even when they in the past would eat certain products they would eat them with other healthy things. Now, we stack unhealthy stuff on top of each other (classic example: white bread, red meat, sugar liquified tomatoes, cheese, mayo, white bread), and I suspect that doing so exacerbates the bad effects of each component.