I think a lot of 'good' habits are often correlated together so it's always suspect when there is a claim that a 'good' habit has some positive health outcome.

I think a lot of 'good' habits are often correlated together so it's always suspect when there is a claim that a 'good' habit has some positive health outcome. it could even be worse where the 'good' habits have no effect and the 'good' habits are just a side effect of a 'good' package of genes which is what really produces the positive health outcome.