Fat produces hormones that greatly affect weight loss and gain
October 11, 2004
By Dr. William Schamadan
Fat is not just an extra layer of padding or insulation. New research shows fat is actually an endocrine organ, like the thyroid or pancreas, and it produces hormones which influence how the body works.
The concept started in 1994, when a research group at Rockefeller University discovered the hormone, which has been named leptin. Leptin is produced by the fat cells and sends signals to tell the brain whether to increase your appetite or to curb it. When first discovered, leptin was thought to be the answer to obesity. If we could control this hormone and use it to curb appetite and burn more calories, our national fat problem would be solved. Unfortunately, its just not that simple.
Continued research showed the control of the body's fat stores is a complex process of interactions among a whole group of hormones produced by the fat cells, and even the stomach.
- Leptin. When you gain weight, the fat cells release
more leptin, which should make you eat less and burn
more calories. But, the more fat you accumulate, the
less effective leptin becomes. When you lose
weight, the cells release less leptin. That makes
you want to eat more and makes it difficult to keep
off the weight you have lost.
- Adiponectin. This hormone helps insulin pull sugar from the bloodstream into the cells, where it is used for fuel or stored as glycogen. The more fat you have, however, the less adiponectin your fat cells secrete. This is probably part of the answer to insulin resistance and the development of type 2 diabetes.
- Inflammatory proteins. Fat cells can release proteins (interleukin-6 and tumor necrosis factor-alpha) that cause low-level inflammation throughout the body. The inflammation is too subtle to produce fever or pain, but it still causes trouble. Inflammation encourages the rupture of atherosclerotic plaques which have formed in blood vessels, leading to a heart attack or stroke.
- Ghrelin. This strangely spelled hormone is released by the stomach when you lose weight. It makes you hungry and want to eat more, so it is tougher to keep the weight off.
Some people store fat in their thighs or buttocks or arms and assume a "pear shape." Other folks, usually men, store fat in their abdomen (visceral fat) and assume an "apple" shape. The visceral fat is much more active in secreting the hormones that seem to make everything worse; diabetes, heart disease, stroke, etc.
The prescription to reverse this trend is (you guessed it) diet and exercise. You already know my feelings about the benefits of exercise, but let me share some interesting data in support of very-low-fat diets, a la Pritikin and Ornish. The researchers at the University of Washington in Seattle, showed very significant weight losses during three months by changing people to a very-low-fat diet without reducing the number of calories they were eating. That's not new information, but while their leptin levels dropped as expected, it did not increase feelings of hunger. They inferred the diet increased the brain's sensitivity to leptin. What's more, there was no rise in ghrelin, the stomach produced hormone that increases hunger. This hormone rises with weight loss from any other diet and makes it more difficult to maintain or continue weight loss. Perhaps these hormone responses can help explain the success or failure of other dietary approaches to weight loss.
Excess fat is not a passive risk to health, but is really an active (endocrine) participant in the production of disability and disease. Your well being will benefit from your getting actively involved in fighting it.
Source:www.mansfieldnewsjournal.com
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