Kidney stone clues

Nutrition Action Healthletter, June, 2004

Want to dodge a kidney stone? In a study of 96,000 women aged 27 to 44, those who drank the most fluid (average: 13 1/2 cups a day) bad a 32 percent lower risk than those who drank the least (five cups a day). Nine cups a day cut the risk by 20 percent.

Women who got the most calcium from foods (1,300 mg a day) had a 27 percent lower risk of stones than women who got the least (540 mg a day). Calcium supplements had no impact on risk.

Phytate--found largely in beans and whole grain cereals and breads--also seemed to protect kidneys. In contrast, eating more sugar (sucrose) was linked to a higher risk.

What to do: Here's one more reason to drink fluids, avoid excess sugar, and eat more beans, whole grains, and (low-fat) dairy.

Arch. Intern. Med. 164: 885, 2004.