[robbedpeter]

Nobody is going to be smoking 20+ joints per day, every day. Cigarettes also have more carcinogenic chemicals per unit of inhaled smoke, so it's not a 1 to 1 comparison. Smoking weed also has anti-inflammatory effects, and other chemistry that counters some of the negative effects of combustion.

It's not great for you, but its level of harm is closer to vaping than to smoking cigarettes.

If someone does persistently smoke comparable amounts of marijuana per day, they're also likely to have a substance abuse issue. I don't think even Snoop or Willie do it like that.

[bko]

Marijuana has other negative side effects especially when used by people under 18. I don't know about the long term evidence, but I would bet there are cognitive issues associated with regular use, such as short term memory loss.

It is also surprisingly common and socially accepted to drive while under the influence.