Appetite
Leptin is a protein that's made in the fat cells, circulates in the bloodstream, and goes to the brain. Leptin is the way your fat cells tell your brain that your energy thermostat is set right, Lustig says. While ghrelin is an appetite-stimulating peptide, leptin is an appetite-suppressing one. Ghrelin, secreted from the stomach, particularly influences the metabolism of fat tissue by promoting its storage during hard times. Leptin and ghrelin function interdependently in healthy humans. Leptin acts as a hormone that modulates the size of the adipose tissues in the body. It regulates food intake and body weight. Leptin also acts on specific receptors in the hypothalamus to inhibit appetite through both counteractive and stimulatory mechanisms: Leptin is a cell-signalling hormone vital in the regulation of appetite, food intake and body weight. Studies have shown that an absence of leptin in the body or leptin resistance can lead to uncontrolled feeding and weight gain. Leptin is a complex hormone that helps regulate food intake and body weight. A part of your brain controls leptin levels in conjunction with your body fat mass. Because leptin suppresses appetite, it may seem beneficial to raise your level. It's more complex than that, however. When fat mass decreases, the level of plasma leptin falls so that appetite is stimulated until the fat mass is recovered. There is also a decrease in body temperature and energy expenditure is suppressed. By contrast, when fat mass increases, so do leptin levels and appetite is suppressed until weight loss occurs. The truth about the hormone leptin and obesity. It's been called the  obesity hormone or fat hormone -- but also the starvation hormone.. When scientists discovered leptin in 1994, excitement arose about its potential as a blockbuster weight loss treatment. Even today, the Internet is loaded with sites that sell leptin supplements.
http://www.webmd.com/diet/obesity/the-facts-on-leptin-faq http://montereydiet.com/ghrelin_and_leptin.html http://www.news-medical.net/health/What-Does-Leptin-Do.aspx http://www.news-medical.net/health/What-Does-Leptin-Do.aspx http://www.livestrong.com/article/41429-foods-stimulate-leptin-response-body/ http://www.news-medical.net/health/What-Does-Leptin-Do.aspx http://www.webmd.com/diet/obesity/the-facts-on-leptin-faq
what does leptin stimulate