Marijuana use is associated with higher daily caloric intake. In the NHANES III and CARDIA study, heavy cannabis users had ;20% higher calorie intake than nonusers (25,26). The increase in calories was from higher intake of all macronutrients. Specifically, the frequency and amount of consumption of soda, cheese, salty snacks, pork, and alcohol was higher in cannabis users. Consistent with other studies, the quality of diets consumed by cannabis users was poor (27). Furthermore, the percent of daily calories derived from carbohydrates relatively rich in simple sugars was significantly higher in marijuana smokers. These findings are consistent with human and animal studies demonstrating that cannabinoids stimulate food intake, specifically highly palatable sweet-tasting foods (28). Cannabis smokers in our study exhibited characteristics typically observed in marijuana smokers in the general population."

Source

Muniyappa, Ranganath, MD, PhD, et al., "Metabolic Effects of Chronic Cannabis Smoking," Diabetes Care, e-published before print on March 25, 2013. DOI: 10.2337/dc12-2303. Clinical trial reg. no. NCT00428987, clinicaltrials.gov.
http://care.diabetesjournals…