Maybe I’m an idiot. I can’t imagine being overweight or obese is good for anything—except winning belly-flop competitions—but apparently there is a school of thought out there that high body mass index helps build strong bones. Luckily, a new study shoots that pieces. Turns out muscles keep bones strong, not fat.
The researchers looked at bone density and volume, as well as lean and fat mass, in 768 men aged 25 to 45, including 296 pairs of brothers.
After the researchers adjusted for weight, they found that men's bone mass and volume fell steadily as their percentage of fat mass increased, while bone size rose in tandem with lean mass. Fat in the trunk area had a stronger influence on bone size than fat on the arms and legs.
"Lean mass," the researchers conclude, "is the major determinant of bone size, providing further evidence that bone size is adapted to the dynamic load imposed by muscle force rather than passive loading" by fat.
Dr. Fuhrman agrees with the muscle-bone link, saying, “Strong muscles and bones are married together. Working out and strengthening the muscles, thickens the bones in the process.” And in his DVD Osteoporosis Protection for Life you’ll learn how certain exercises tone muscles and build bone density.