Pogue Mahone
Closet Gooner.
The difference I observed in college was that average pot smokers inhaled less actual puffs of smoke per day than the hardcore cigarette smokers would smoke per cigarette (bong hits of high THC California pot). I counted this back then and the heavy cigarette smokers (1 pack+/day) were inhaling more puffs of smoke in a single day than the average pot smokers would take in 3-4 weeks. Even assuming the smoke is equaling damaging, the cigarette smokers were inhaling exponentially more of it and far more regularly throughout the day.
Bong hits certainly less damaging than joints, as the smoke is cooled and (partially) filtered by the water. You’re still setting stuff on fire and sucking smoke right down to the bottom of your lungs. Which is not going to do them any good, put it that way.