An orthopedic surgeon told me that smoking exacerbates osteoporosis. What is the mechanism of action? Does smokeless tobacco have the same effect?
—Libby M. Kokott, DO, Portsmouth, Ohio

Current smoking of more than one pack of cigarettes per day is considered a risk factor for osteoporosis, although evidence of this effect is best described as modest. The exact mechanism is unknown, but impaired absorption or utilization of calcium or vitamin D is suspected, and poor overall nutrition and weight loss may play a role as well for some smokers. I am not aware of any studies on the effect of smokeless tobacco and bones.
—Jack Waxman, MD (106-3)