[AstralStorm]

They aren't controversial but effect sizes on mood are small. You do not fix depression with small mood changes.

A lot of this research is further confounded by the simple fact that depressed people exercise less as well as eat less healthy. Epidemiology does not show causation here, only interventional studies do with tiny effects.

Example is the studies that show having friends makes one less depressed. Obviously people who are depressed regularly have fewer friends because they're avoided.