Toronto, June 30 (IANS): Long-term cannabis use may lead to weight gain, especially among men, says a new research.

"It is known - and often reported by users - that cannabis causes temporary increase in appetite. As to whether it actually causes weight gain in the long term, the available data is limited," said Didier Jutras-Aswad, professor at University of Montreal in Canada.

"The main finding of our study shows that long-term cannabis use indeed influences weight gain," Jutras-Aswad said.

"But above all, we noted that certain factors drastically modify this effect, including gender, level of use, and concomitant cigarette smoking," Jutras-Aswad added.

The researchers found that greater cannabis use led to greater weight gain specifically, in male non-cigarette smokers. And significantly, in male cigarette smokers, the effect was almost the opposite, the study said.

The study followed 1,294 young people who from the age of 12 or 13 agreed to share information each year about, amongst other things, their diet, overall mental and physical health (including weight and height), physical activities, and frequency and levels of their cannabis, alcohol, and/or nicotine use.

For the moment, the researchers are unable to explain the difference between males and females, although they have some hypotheses.

"There are possible psychological differences in men and women in their perception of and preoccupation with weight gain and diet, which could hypothetically explain why men seem specifically sensitive to the complex interaction between cannabis use, cigarette smoking, and weight gain," Jutras-Aswad said.

The study was published in the journal Pharmacology Biochemistry and Behaviour.