Agreed, this is a highly correlative study. However even if meditating doesn't have a direct effect on the brain (it is in some forms just sitting there) it en

Agreed, this is a highly correlative study. However even if meditating doesn't have a direct effect on the brain (it is in some forms just sitting there) it encourages the type of self-reflection that leads to healthier choices. The moments where you go "Oh, activity X is unhealthy and makes me unhappy so I should stop" cause a healthier more balanced lifestyle. So there is a completely non-woo mechanism for why meditation could be improving long term health. Also noteworthy is meditation is a practice that's thousands of years old and there are many different types of it and just because one of them is beneficial doesn't mean they all are.