Low Protein and Osteoporosis in Men?

Low protein intake may be responsible for fractures in older men, according to an observational study that analyzed data from the 2000-2002 Osteoporotic Fractures in Men Study.

Dietary protein is a potentially modifiable risk factor for controlling fractures among older men.

In a Sept. 18 presentation at the American Society of Bone Mineral Research annual conference in Atlanta, lead study author Lisa Langsetmo, M.D., from the University of Minnesota, discussed the investigators’ hypothesis that lower-to-moderate protein intake was associated with an increased fracture risk while high protein intake was not.

“Increased dietary protein intake may be feasible as a low-risk intervention to reduce the risk of hip fracture among older men,” she said.

The study, which included 5,875 men — average age 73.6 years  — had two objectives:  to assess the association of protein intake with low trauma (trauma < fall from standing height) fracture risk and to assess whether the association between protein intake and fracture risk was mediated by falls, body mass index, bone mineral density, appendicular lean mass or gait speed.

Researchers took baseline protein assessment and excluded men with < 500 kcal/d total energy intake or missing ­­> 10 items. The median was 15.9 percent total energy intake with a range from 14.2 percent to 17.8 percent. They defined low protein intake as the bottom quartile and high intake at the top quartile, Dr. Langsetmo said.

According to the analysis, there were 808 low trauma fractures, excluding head, hands, and feet, over 15 years. Results showed a 16-percent lower hip fracture risk, and an 8-percent lower major osteoporotic fracture risk.

Low protein intake was associated with increased fracture risk (HR=1.28, 95 percent CI, 1.08-1.51) compared to those with moderate intake. High protein intake was not associated (HR=1.00, 95 percent CI, 0.84-1.19). There was a two point change in estimates when they were adjusted for falls, body mass index, appendicular lean mass and gait speed.

The protein intake-fracture risk association was dependent on skeletal site, Dr. Langsetmo said. In addition, while the hip fracture association was strong, there was no such association with vertebral fractures.