But who are the "meat eaters" in the studies?

Chris, as I pointed out in another post in this thread: What often gets lost in the studies on meat and associated health problems is that the people in the studies who are identified as "meat eaters" almost always included people who live and eat less healthily in general, including sedentary people and people who eat a unhealthy processed meats along with a largely SADS diet of junk and other processed foods.

By comparison, people who are vegans or who eat a diet high in vegetable and fruit content tend to be more health conscious and live and eat more healthily.  I would bet that the comparisons would be much different if the studies compared so-called meat eaters who chose organic free range type meats and had healthy lifestyles versus vegans who had similar lifestyles.