Fat no protection against fractures

Philip J. Goscienski, M.D.

August 2010

At the beginning of the obesity epidemic that began to accelerate in the 1970s physicians held the opinion that persons who were overweight had fewer fractures, especially those involving the hips, than persons of normal weight. They reasoned plausibly that the extra weight put more stress on leg bones, causing them to become stronger. Further protection came from the padding that hip fat provided in case of a fall.

If a heavier body were truly protective against osteoporosis we would see a decline in the incidence of that condition but the opposite is true. Overweight and obesity increase the risk of osteoporosis. Worse, as obesity has increased four-fold since 1970 among children, they are not only destined to develop osteoporosis in middle age, they are already experiencing an increase in broken bones before they leave high school.

It has become increasingly clear that overweight children are about 3 times more likely to break a bone than their thinner playmates. The risk is higher among girls, a finding that is not surprising since adolescent females are more sedentary than boys. Stated simply, obese or overweight persons of all ages have less bone per pound than persons of normal weight. When they fall they are more likely to snap that relatively thin bone.

Weighing more does make one's skeleton stronger but that is only true if the additional pounds consist of muscle. Muscular activity stresses and strengthens bones; fat weakens it and the reasons are beginning to become clear.

All fat is not the same. Visceral fat is that which insinuates itself between and around the coils of the intestine and is usually associated with a large waist. It is metabolically more active than the fat that accumulates elsewhere and it produces chemicals that promote inflammation. These chemicals, known as inflammatory cytokines, inhibit the formation of bone. It's no surprise then, that persons who are overweight and suffer from type 2 diabetes, heart disease and stroke are more likely to develop osteoporosis, for all of these are influenced by inflammation.

Brisk walking and weight-lifting exercises about 4 days a week lower body fat, build muscle and strengthen bones. It also takes a moderate reduction in calories to melt away fat but by substituting vegetables for potatoes and pasta and having fruit instead of sweets for dessert, that is quite doable.

You'll see the results in a matter of weeks. And eventually, you'll feel it in your bones.

Philip J. Goscienski, M.D. is the author of Health Secrets of the Stone Age, Better Life Publishers 2005. Contact him at drphil@stoneagedoc.com.