This danger is hidden deep in the belly. New research says that for men, visceral (deep belly) fat is a risk factor for bone loss and decreased bone strength. Miriam Bredella, M.D. and her team from Massachusetts General Hospital evaluated 35 obese men with a mean age of 34 and a mean body mass index (BMI) of 36.5.
“It is important for men to be aware that excess belly fat is not only a risk factor for heart disease and diabetes, it is also a risk factor for bone loss, ” said Dr. Bredella in the November 28, 2012 news release. Dr. Bredella is a radiologist at Massachusetts General Hospital and associate professor of radiology at Harvard Medical School in Boston.
“Most studies on osteoporosis have focused on women. Men were thought to be relatively protected against bone loss, especially obese men, ” Dr. Bredella said.
After the Osteoporotic Fractures in Men Study—a multi-center observational study designed to determine risk factors for osteoporosis—indicated that male obesity was associated with fracture risk, the researchers wanted to quantify belly fat and study its impact on bone strength. The men in Dr. Bredella’s study underwent CT of the abdomen and thigh to assess fat and muscle mass, as well as very high resolution CT of the forearm and a technique called finite element analysis (FEA), in order to assess bone strength and predict fracture risk.
“FEA is a technique that is frequently used in mechanical engineering to determine the strength of materials for the design of bridges or airplanes, among other things, ” Dr. Bredella said. “FEA can determine where a structure will bend or break and the amount of force necessary to make the material break. We can now use FEA to determine the strength or force necessary to make a bone break.”
In the study, the FEA analysis showed that men with higher visceral and total abdominal fat had lower failure load and stiffness, two measures of bone strength, compared to those with less visceral and abdominal fat. There was no association found between age or total BMI and bone mechanical properties.
The results also showed that muscle mass was positively associated with bone strength.
