no, it doesn't. there is no reputable evidence it kills braincells. > "for many just learning about cannabis, there's a lasting buzz of often repeated claims. neurologist dr. david bearman took on the most common, including what he called "the bogus claim of brain damage." he wrote, "cannabis does not cause brain damage. it is neuroprotective," pointing to the story's origin as long-debunked research."   ed-kill-brain-cells
United States