When I told my husband that the use of cannabis is being linked to a five percent increase in lung cancer risk -- that's 15 new cases each year in New Zealand where a study was just conducted -- he seemed to think this risk is comparable to his dying from a grasshopper landing in his eye.

A scientist John is not, but his thoughts on the matter seem to parallel international thinking on the drug which goes something like this: the risk marijuana use has on cancer incidence is so very low it's hardly worthy of much worry.

A California study of more than 1600 people last year found no link between cancer and smoking the drug, despite researchers' prediction they would find some kind of connection.

New Zealand researchers have found a connection, though, and however small it may seem, they say it's significant.

They found the risk of developing lung cancer increased by about eight percent each year for people whose cumulative exposure equated to smoking one joint per day -- about the same as the increase for someone who smokes one pack of cigarettes per day. They also found the younger someone starting smoking cannabis, the greater the risk and that contributing risk factors include smokers' deeper inhalation and the tendency to hold smoke in their lungs.

Cannabis, the most commonly used recreational drug in the world with 161 million users, has been thought to have a protective effect against cancer due to its chemical THC, which appears to kill aging cells and keep them from becoming cancerous. This study may prove otherwise.