Exercise may cut kidney stone risk

Study: Obesity ups risk of the ailment

Women have another reason to exercise: It may help prevent kidney stones. You don’t have to break a sweat or be a super athlete, either. Even walking for a couple hours a week can cut the risk of developing this painful and common problem by about one-third, a large study found.

“Every little bit makes a difference” and the intensity doesn’t matter — just getting a minimum amount of exercise does, said Dr. Mathew Sorensen of the University of Washington School of Medicine in Seattle.

He led the study, which was to be discussed Friday at an American Urological Association conference in San Diego.

About 9 percent of people will get a kidney stone sometime in their life. The problem is a little more common in men, but incidence has risen 70 percent over the last 15 years, most rapidly among women.

Obesity raises the risk as do calcium supplements, which many women take after menopause. A government task force recently advised against supplements for healthy older women, saying that relatively low-dose calcium pills don’t do much to keep bones strong but make kidney stones more likely.

Why might exercise help? It changes the way the body handles nutrients and fluids that affect stone formation. Exercisers sweat out salt and tend to retain calcium in their bones, rather than having these go into the kidneys and urine where stones form. They also tend to drink water and fluids afterwards, another plus for preventing stones.

Exercise is known to cut the risk of conditions that raise the risk of kidney stones.