Recently researchers have discovered that the prevalence of obesity is paradoxically much lower in cannabis users as compared to non-users and that this difference is not accounted for by tobacco smoking status and is still present after adjusting for variables such as sex and age (Le Foll, 2013). In abdominal obesity, the ECS is generally up-regulated in central and peripheral tissues and its blockade results in positive metabolic changes (Silvestri, 2012).
A CB1 antagonist that attempted to harness these positive effects on weight loss was approved by the FDA in February 2006 under the name Rimonabant. However, because CB1 antagonism in the central nervous system causes severe depression and suicidal thoughts the drug was removed from the market shortly after (O'Keefe, 2013).
More recently researchers have focused on developing new CB1 antagonists that can't cross the blood brain barrier restricting them to the periphery. By using compounds that solely target the peripheral ECS, weight loss treatment using this strategy should no longer be accompanied by such negative psychological effects.