Leptin, the chemical which has something to do with appetite and fat formation, has been increasingly interesting to researchers. It has been discovered, for example, that when the body goes into famine -survival mode (and that happens when people 'diet' as well), it stops producing leptin and this causes the individual to be very hungry and also to form more fat when food is eaten (in case there is food, to store it up). Leptin levels continue to be low for as long as two months after a famine or a diet and this explains, in part why dieters coming off a diet are so ravenously hungry, why they have an affinity to overeat ('diet related binge-ing') and why they gain weight back so quickly after a diet. There are doctors treating underweight by having the individual go on a diet as dieting is also a very good way to gain weight.
But researchers have recently discovered something else interesting about Leptin - it seems to influence the formation of bone and when the levels get low (as during a diet or chronic starvation), bone formation seems to stop completely. On the other hand, in rats who were obese, or even in those well nourished, bone formation was normal or even better than normal. (The bone formation may be more in obese individuals because obese individuals are thought to be 'Leptin resistant' i.e. their bodies may ignor the high levels of leptin they often have, and still cause a big appetite and the formation of fat).
This may explain, in part why women athletes, most of whom do not get sufficient nutrition (in order to be able to be 'acceptable' to a world which rejects largeness in women) often get osteoporosis. It might be the low levels of leptin from the chronic starvation or semi-starvation causing this, if the latest research rings true.
It was an international team of investigators, led by Dr. Gerard Karsenty from the Baylor College of Medicine, with support from the National Institutes of Health, which discovered the link between leptin, the brain, and bone density.
The researchers are a bit upset that it was the 'obese' rats who had dense bones. Actually osteoporosis is rare among obese human beings also.
Now, the researchers will undoubtedly try and look for a way to encourage
bone density and still remain fashionably thin. That ought to keep them
off the streets for an hour or two!
Source: NIH bulletin
or... Use back arrow on Browser to go back to home page