I guess dry mouth increases incidence of periodontal disease. Some people get cannabinoid hyperemesis syndrome, but that's somewhat rare.
With long term, increasing use, I personally experienced insomnia, anxiety, and lack of appetite. Only with 1g of dabs a week. YMMV. I've quit weed and alcohol, but I consider weed usually a lesser evil. Alcohol really fucked my depression up.
Smoking anything is bad for your lungs. Carcinogenic most likely.
Not all cannabis is consumed via smoking.
/pedant who finds it funny to comment on this because I don't even consume cannabis what with being allergic to it.
Let's assume the user isn't smoking or gaping it, but eating it instead.