Table 3.

Multivariable adjusted mean mammographic density and 95% confidence intervals by total vitamin D and calcium intake at baseline, Women's Health Initiative Mammogram Density Study (n = 808).

	Vitamin D (IU)
Calcium (mg)	< 200	200 - 399	≥ 400
< 750	7.5 (5.7, 9.2)	2.4 (0.0, 5.7)	2.8 (0.0, 5.7)
750 - 1199	10.5 (7.2, 13.8)	6.3 (3.9, 8.6)	4.0 (1.1, 6.9)
≥ 1200	7.3 (3.0, 11.5)	8.8 (3.9, 13.7)	4.5 (2.5, 6.5)
			P int = 0.99

Adjusted for covariates in Model 1: age, race/ethnicity, body mass index, age at menarche, parity, oral contraceptive use and duration, previous HT use/duration, HT trial randomization assignment, family history of breast cancer, education, alcohol intake, smoking, total calorie intake, physical activity, Gail risk, and use of multivitamins.