Dietary calcium decreases stone formation in women

A higher intake of dietary calcium appears to decrease the risk of kidney stone formation in women, according to findings from the Nurses' Health Study II. Interestingly, supplemental calcium had no impact on stone risk.

During an 8-year period, women aged 27 to 44 years with no history of kidney stones were questioned about their dietary intake. After adjusting for relevant risk factors, those women who ate three or more servings of dairy each day reported a lower incidence of kidney stones than those who did not (p=.007). Supplemental calcium, sodium, animal protein, and sucrose may increase the risk, the authors said.

The study appears in Archives of Internal Medicine (2004; 164:885-91).