[metrokoi]

Smoking decreases the amount of certain enzymes that COVID binds to in order to infect the lungs. Less enzymes means a lesser chance of catching the virus, but if caught, the person will likely have a more severe case due to the decreased lung capability.[0][1] The figures that I have seen previously did show a very significantly decreased risk of catching COVID, and I'm surprised it hasn't been investigated far more.

Edit: I had that wrong, it seems nicotine increases ACE2, but also binds with ACE2 decreasing the amount of available enzymes overall that COVID could bind to.[2]

[0]https://en.wikipedia.org/wiki/Angiotensin-converting_enzyme_... [1]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7191112/ [2]https://arxiv.org/abs/2004.14943