April 28, 2006 (New York) -- A system in the body that plays a role in getting the "munchies" may be the latest battleground in the war on obesityobesity, according to experts at a presentation sponsored by the American Medical Association.
The endocannabinoid system affects many body processes, including the control of food intake and metabolic functions such as energy, sugar, and fats. Studies have shown that the endocannabinoid system is revved up in people who are obese, causing weight gain and its related risks.
"What many people are looking at as a lack of willpower could have some physical basis," says Louis J. Aronne, MD, director of the Comprehensive Weight Control Program at New York Presbyterian Hospital-Weill Cornell Medical Center and a clinical professor of medicine at Weill Medical College of Cornell University in New York. Simply put, when the endocannibinoid system is overactive, people eat more, leading to weight gain.
But blocking the endocannabinoid system may do more than just reduce weight; it may also reduce related risk factors. Because this system also affects metabolic functions, putting the lid on it fights risk factors that lead to diabetesdiabetes.
Five drugs are being developed that block the endocannabinoid system, including Acomplia, the "antimunchies" drug, so-named because it acts like marijuana in reverse, curbing appetite.
EC system 101
When your endocannabinoid system is overactive, the deck is stacked against you. "Its effect on the brain is to increase hunger and decrease satiety, and drive the desire for palatable food," he explains. "In the gastrointestinal tract, it interacts with other hormones ... to make you feel hungrier."
What's more, it impairs the cells' ability to use blood sugar. This sets the stage for diabetes.
Studies in both animals and humans show that when the endocannibinoid system is stimulated, it leads to weight gain, increases body fat, and slows the action of insulin. Taken together, these effects are called the metabolic syndromemetabolic syndrome, which predisposes a person to developing heart diseaseheart disease and diabetes.
Is Blocking the EC System a Panacea?
Soon after discovering the endocannabinoid system, researchers began to find sites all over the body called cannabinoid receptors. Blocking these receptors may rein in the overactive endocannabinoid system and reduce weight as well as improve other related risk factors. Acomplia is designed to do just that.
A recent study published in The Journal of the American Medical Association showed that people who took Acomplia were able to lose weight, maintain their weight lossweight loss, reduce the level of fats in the blood and fat deposits, and improve insulin action as long as they took the drug, thus reducing their risk factors for heart diseaseheart disease and diabetesdiabetes.
Drugs that block the endocannabinoid system may provide "one more tool in the tool box to deal with obesityobesity," says Sharonne N. Hayes, MD, director of the Women's Heart Clinic at the Mayo Clinic in Rochester, Minn., and an associate professor of medicine and cardiovascular disease at the Mayo Clinic College of Medicine, also in Rochester.
"Right now all we have to treat the metabolic syndromemetabolic syndrome is lifestyle changes such as diet and exercise, and just losing 10% of body weight that can be very effective, but there are many people who can't meet this goal," she says, "If we had a tool that had some impact on the underlying [cause], that would be great," she says.
"We need to be hopeful, but it is premature to believe that this new class of drugs will be the answer," she tells WebMD.