Some of you may have heard of leptin and some of you may be hearing the word for the first time. Leptin is a hormone produced by fat cells that signals your brain that you’ve had enough food. If you’re serious about understanding appetite and weight-related body chemistry, here’s the quick-and-dirty on leptin.

According to an ENVIRONMENTAL NUTRITION (February 2011) article, Lessons About Leptin, Weight and Your Eating Environment, when you eat more calories than your body needs, they are stored in fat cells as fat. As fat is socked away, your leptin levels elevate and are released into your bloodstream, alerting your brain that you’ve consumed enough nutrients. Conversely, by losing weight through reducing fat stores, your leptin levels plummet, signaling your brain to believe that your body is in starvation mode which increases food-seeking behavior. Throughout history, this balance of stored calories evolved to help us take in the amount of food we needed to survive.

Discovered in 1994, leptin was at first thought to be the panacea to curbing obesity. The thought was to increase leptin to suppress appetite, which would lead to eating less and losing weight, and studies were conducted upping leptin through injection in obese patients. This increase was based on the erroneous assumption that obese people have low levels of leptin and, therefore, do not receive a body signal that they’re satiated—which turns out not to be the case.

Martin G. Myers, Jr., M.D., Ph.D., associate professor of internal medicine at the University of Michigan Medical School explains that “…if you have someone very obese…adding extra leptin doesn’t appear to help with weight loss. Leptin can’t do the job all by itself with environmental factors that promote overeating.” That said, it appears that recent clinical trials have found that leptin in combination with a hormone called amylin may yield more promising results. However, Myers cautions not to look to leptin to curb your eating and warns against supplement scams that promise quick weight loss through leptin manipulation.

He does encourage people to recognize the impact of their environment on their eating, including not keeping tempting foods around. Although, as a generalization, I disagree with this advice, I do believe that reducing plate and portion size and whisking food off the table after a meal helps. In the long run, however, troubled eaters have to learn how to live in a goodies-laden food world by managing their urges for unwanted eating.