3 ms·
I wonder if people with higher vitamin D levels are more likely to touch grass. It's good for your immune system to go outside.
by hooverd 4y ago
I wonder if people with higher vitamin D levels are more likely to touch grass. It's good for your immune system to go outside.
- nradov 4y agoProbably. That's one of the confounding factors which makes this difficult to study in a really rigorous way.
- selimthegrim 4y agoPeople who smoke are probably more likely to smoke outside too with the recency of indoor smoking bans