Leptin is a hormone that is essential in the regulation of appetite and metabolism. Since its discovery by scientific researchers in 1994, problems with leptin production and levels in the body have been identified as a major contributor to a number of health problems, including obesity. Leptin's function, while not yet fully understood, is the focus of a large amount of research by both nutritionists and health professionals.
Leptin is a hormone that reacts with cell receptors in the brain's hypothalamus gland to signal to the body when it has reached satiety--in other words, telling the body that it has had enough to eat and to stop consuming food. Leptin is produced primarily by the body's adipose tissue (fat cells), but it is also synthesized in smaller amounts by the ovaries, the pituitary gland, the liver and bone marrow.
Like all hormones, leptin acts by binding with cell receptors and triggering those cells to either release a biochemical (such as another hormone or enzyme) or to perform a particular action. When leptin reacts with hypothalamus receptors, it stimulates the hypothalamus to signal the brain to stop eating in order to prevent overeating and unnecessary weight gain.
Leptin has been also identified as being vital for the proper functioning of both the male and female reproductive organs, as well as increasing the rate of glucose metabolism. Leptin levels are also thought to be directly correlated to an individual's energy levels.
Leptin and Obesity
An individual whose hypothalamus is responding appropriately to leptin has a built-in check against excessive weight gain--the leptin-induced feeling of satiety. However, if a person is obese, their hypothalamus gland can become resistant to the effects of leptin. As they accumulate more fat cells, the fat cells produce ever greater amounts of leptin, all the while making a hypothalamus that responds more and more feebly to the hormone.
Problems with Leptin
Excessively high leptin levels in the blood or leptin that is not synthesized properly has been linked to a number of health problems, in addition to obesity. These include insulin resistance, often leading to diabetes; imbalances in the male and female sex hormones, resulting in reproductive problems; high blood pressure; high cholesterol; heart disease; and increased risk of developing Alzheimer's disease.
The Leptin Diet
After realizing leptin's importance in the body's energy metabolism system, many nutritionists and health care professionals have begun recommending that controlling weight lies controlling the levels of leptin in the body. Byron and Mary Richards, the authors of "Mastering Leptin: The Leptin Diet, Solving Obesity and Preventing Disease," suggest five main eating strategies to reduce the effects of leptin resistance in overweight individuals. The five strategies include eating three meals a day with no snacks in between, reducing the amount of carbohydrates consumed and never eating after dinner.