“According to a new British study, marijuana leaves (not the buds that Willie Nelson loves so dearly) contain two compounds that boost the metabolism of mice, leading to lower levels of fat and cholesterol in the body — the latest addition to a growing body of evidence that marijuana may be useful in countering ailments related to obesity. One study in March found that a brain chemical similar in structure to an active compound in cannibis could help people shed weight, while another study last September concluded that pot smokers were less likely to be obese than non-potheads, though for reasons that remain unclear.   

The two compounds, THCV and cannabidiol, boosted the rodents’ metabolisms — reducing fat levels in their livers and cholesterol levels in their bloodstreams — and also made the mice more sensitive to insulin and protected the cells that produce insulin, “allowing [the cells] to work better and for longer.” The combined effects improved the mice’s ability to burn off energy.

And the compounds didn’t make mice hungry the way smoking weed affects humans?
Actually, the compounds were found to have an appetite-suppressing effect, but the effect only lasted for a short time.”

 http://news.yahoo.com/marijuana-could-help-cure-obesity-related-diseases-175900182.html