A whole pile of the studies are observational and not placebo-controlled, nor randomized.
Therefore, other factors beyond the consumption itself can't be ruled out, such as differences in education, religious beliefs, non-religious beliefs, open-mindedness, etc.
Trying to answer the question of why alcohol clinically has the effects that it does is a hard battle. The molecule has wide-ranging effects, it doesn't by any means hit any particular receptor. It goes wherever water goes in the body and disrupts every cell membrane in the body, among other effects.
And that's if the health benefits have anything to do with the clinical effects at all.
Therefore, other factors beyond the consumption itself can't be ruled out, such as differences in education, religious beliefs, non-religious beliefs, open-mindedness, etc.
Trying to answer the question of why alcohol clinically has the effects that it does is a hard battle. The molecule has wide-ranging effects, it doesn't by any means hit any particular receptor. It goes wherever water goes in the body and disrupts every cell membrane in the body, among other effects.
And that's if the health benefits have anything to do with the clinical effects at all.