Last dance with Mary Jane, one more time to … stop weight gain? According to a new study by researchers at the University of Nebraska, the Harvard School of Public Health, and Beth Israel Deaconess Medical Center, regular marijuana users are skinnier than those who have either never tried the drug, or don’t use it regularly. The study, which looked at 4,600 adults, found smaller waist circumferences in the 12 percent who identified themselves as regular weed smokers. On top of the skinny factor, researchers also found higher levels of “good cholesterol” (HDL) in those who smoke cannabis often.