I've read about saunas, and studies were saying people who spent 19 minutes, 4-7 days a week in a 174F sauna had a 66% less chance of dying from all causes. An

I've read about saunas, and studies were saying people who spent 19 minutes, 4-7 days a week in a 174F sauna had a 66% less chance of dying from all causes. And then marketing people tried conflating IR saunas with conventional saunas, which nobody has studied and might not have the same efficacy. I don't know either but I suspect hot air, especially in the lungs is a big part of the mechanism.