It seems like the jury on marijuana and weight gain has been out for a while. Cannabis is known to increase appetite, sure, but most daily tokers you know are skinnier than Justin Bieber.

A new study attempts to answer the vexing question.

University of Montreal researchers, led by Jennifer O’Loughlin, looked at data from 1294 young people who agreed to share information each year on their diets as well as about their alcohol, tobacco and marijuana use.

The guarded conclusion is that long-term cannabis use can indeed be associated with weight gain. According to a summary:

The main finding of our study shows that long-term cannabis use indeed influences weight gain. But above all, we noted that certain factors drastically modify this effect, including gender, level of use, and concomitant cigarette smoking.

Weight gain was more noted in men.

“In male non-cigarette smokers, greater cannabis use led to greater weight gain,” says University of Montreal professor Didier Jutras-Aswad. “And significantly, in male cigarette smokers, the effect was almost the opposite.”

Why aren’t women affected the same way? It’s not clear. Researchers suggest hormones might play a role.

“THC and nicotine do not affect the neurobiological circuits controlling hunger in the same way in men and women,” Jutras-Aswad says.

Meanwhile, that old stereotype of a munchies-obsessed toker? The struggle is real.