Table 4.

Calcium and vitamin D intake and breast density

First author (ref.), year, study placeYears of data collectionStudy designSample sizeComparison*EstimatesVariables adjusted for
Vachon (62), 2000, United States1990-Cross-sectional study1,508Total vitamin D (IU/d)Mean (95% CL) % breast densityAge, BMI, WHR, physical activity, age at menarche, age at first birth and no. births combined, alcohol, smoking, family history of breast cancer, HRT, and oral contraceptive use (premenopausal women only)
Premenopausal, ≤188.740 (34, 45)
Premenopausal, >562.842 (35, 48)
Postmenopausal, ≤188.732 (30, 35)
Postmenopausal, >562.832 (30, 34)
Holmes (63), 2001, United States1986-1990Cross-sectional study885PremenopausalMean % density across quintiles (P)Age and BMI
Dietary vitamin D intake45, 41, 38, 42, 33 (0.02)
Dietary calcium intake44, 47, 37, 37, 37 (0.01)
Bérubé (61), 2004, United States1988-1990Cross-sectional study543Dietary vitamin D (IU/d), 200+ vs <50OR (95% CL)§: 0.24 (0.11, 0.53)Age, BMI, age at menarche, no. birth/age at first birth, oral contraceptive use, menopausal status, HRT, family history of breast cancer, education, alcohol, caloric intake, and smoking
Dietary calcium (mg/d), 1,000+ vs <499OR (95% CL)§: 0.24 (0.10, 0.57)
Bérubé (64), 2005, Canada2001-2002Cross-sectional study1,560Vitamin D (100 IU increase)β (P)Age, BMI, age at menarche, no. birth, age at first birth, duration of oral contraceptive and HRT use, history of breast biopsies, family history of breast cancer, education, alcohol, caloric intake, physical activity, and smoking
Premenopausal
Food−1.8 (0.008)
Supplements−1.0 (0.16)
Total−1.4 (0.004)
Postmenopausal
Food−0.4 (0.40)
Supplements0.4 (0.29)
Total0.1 (0.76)
Calcium (100 mg increase)
Premenopausal
Food−0.7 (0.005)
Supplements−0.7 (0.06)
Total−0.8 (0.0004)
Postmenopausal
Food0.1 (0.72)
Supplements0.2 (0.46)
Total0.1 (0.49)
Masala (65), 2005, Italy1993-2000Longitudinal study1,668Dietary calcium (tertiles), T3 vs T1OR (95% CL): 0.67 (0.47, 0.94)Age, education, BMI, menopausal status, and total caloric intake
  • * The associations are presented by menopausal status whenever the studies reported them separately or the studies were restricted to either premenopausal or postmenopausal women. Otherwise, the associations for a combination of premenopausal and postmenopausal women are presented.

  • Assessment was based on mean (95% CL) of % breast density.

  • The study was published as an abstract. No detailed information on the 95% CL was presented.

  • § This study compared women with mammographic density of ≥70% with those with mammographic density of ≤30%.

  • β, estimated from linear regression analyses, represented absolute mean decrease or increase in breast density (%) for increments of 100 IU vitamin D or 100 mg calcium, respectively.

  • The study compared women with high mammographic breast density with those with low mammographic breast density.