Researchers Establish Link Between Obesity, Weak Bones

New research from the University of Georgia shows a link between obesity and weaker bone structure in young adult women.

The participants in the study were 115 women all aged 18 or 19. Some of the participants had normal body fat, less than 32% and some had higher, above 32%. They were all given advanced three-dimensional bone scans.

The researchers adjusted for any differences in the muscle mass right around the bones and they were able to determine that those with the high percentages of body fat had bones that were from 8% to 9% weaker than the ones with a normal percentage.

The previous studies that focused on the connection between obesity and healthy bones used a two-dimensional bone densitometer, the same one that is used in screening for osteoporosis. But it does not figure in the shape of the bones and geometry, both of which play a big part in the strength, or lack of it, in bones.

By using the three-dimensional imaging technique they were surprised to find that all of the participants in both groups have bone strength that is similar when they are compared to each other when they do not take into account the muscle mass. Muscles exert force on the bones and this stimulates bone growth. Those who are obese have more muscle around their bones, which leads some researchers to believe that being overweight leads to better bone health.

But, when the researchers adjusted the results based on the amount of muscle, they determined that a person who is obese is actually not making enough bone in relation to the amount of muscle. The reason why this was never discovered before is because no on else has used the three-dimensional scan

They are not sure exactly how having excess fat is able to adversely affect bone strength, but in studies done with overweight mice they discovered that they make more fat cells in the bone marrow and fewer fat cells in the bone cells themselves. Fat cells and bone cells actually spring from the same precursor, which leads to the belief that as far as obese people are concerned, the production of fat cells is heightened, while the production of bone cells is put on the back burner, so to speak.