Far from being inert and unchanging, a mere scaffolding to which the body's muscles and organs attach themselves, bones change constantly. Old bone cells die. New ones are born. But that's not all. According to an exciting new discovery, bones play a role in regulating blood sugar levels and fat deposits.How is this possible? Bones act like a kind of endocrine organ, releasing osteocalcin, a hormone that influences bone formation. This hormone also increases both insulin production and the body's insulin sensitivity. It also reduces fat stores. Basically, osteocalcin levels in the bones are linked to blood sugar and body fat levels, and there is some sort of interaction back and forth.
It's a surprising finding for the uninitiated. However, some scientists are saying it makes sense when you think about it. Says Ronald Kahn, director of Harvard's Joslin Diabetes Center, "Obviously there does need to be some coordination between skeletal growth and body mass. If you carry around extra weight, your bones need to hold up under the extra pressure, so it's not surprising that your bones have a sense of body fat."
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