||While there are conflicting studies as to the extent of damage caused by cannabis smoking and the long term effects of the psychoactive compounds on a person's mental state, I can say for certain that smoking anything is bad for one's health. The combustion of any organic matter produces all kinds of toxic and reactive compounds and gases. However, everyone is exposed to various levels of these compounds just by living in modern society. One must assess the amount of risk and exposure one is comfortable living with based on the level of exposure experienced.|
It's important to recognize that smoking three joints a day qualifies as heavy use. Because joints are unfiltered, this is probably equivalent to around a pack of cigarettes a day. This level of cigarette smoking has definitely been shown to be harmful to the lungs. Do you ever notice coughing, difficulty breathing, throat irritation, or lung or throat infections? All of these are short term symptoms of heavy smoking and suggest that long-term use at this level may have signifant long term effects.
If you find that you are uncomfortable with the risk, you may want to change smoking styles to something less harmful, or cease smoking all together. There seems to be some data that shows that smoking out of a water pipe or bong is *not* that much better than joint smoking (note that the less you apply a flame to the cannabis, the less toxic compounds are produced, thus a "cherrying" joint may be less harmful than repeatedly lighting a bowl or bong). Vaporization is probably the safest way to "smoke" cannabis, as the psychoactive compounds are practically "steamed" out of the plant matter and less smoke is produced. Another alternative is eating, which has its own benefits and drawbacks. The final option is abstanance. If you feel that the drawbacks outweigh the benefits, stop.