Intake of calcium and vitamin D was measured in 1991, 1995, and 1999 by a food frequency questionnaire.Results After adjustment for age, parity, smoking status, and other risk factors, women in the highest quintile of total vitamin D intake (median, 706 IU/d) had a relative risk of 0.59 (95% confidence interval, 0.40-0.86) compared with those in the lowest quintile (median, 112 IU/d) (P = .01 for