You might be joking, but higher altitude also means less oxygen, which translates to reduced oxidation and less risk of cancer. I'm on my cellphone so I don't

You might be joking, but higher altitude also means less oxygen, which translates to reduced oxidation and less risk of cancer. I'm on my cellphone so I don't have the paper on hand, but there was a big study where they compared lung cancer rates in different geographic areas and found that the highest cancer incidence was at sea level, whereas the lowest was at higher elevations. They tried controlling for other obvious variables but elevation was unquestionably the best explanation. Oxidation may explain plaque in arteries.