Table 5

Multivariate-adjusteda mean value (95% CI) of percent breast density by quartiles of vitamin intakes

VitaminAllb,c (n = 1508)Premenopausal (n = 283)Postmenopausal (n = 1225)
Meana95% CInMeana95% CInMeana95% CI
Vitamin A (IU)
≤9826.435(29–34)10339(35–47)27432(33–37)
>9,826.4–14,347.736(31–35)7044(36–48)30733(33–38)
>14,347.7–21,012.035(30–34)6040(33–45)31732(32–37)
>21,012.035(29–34)5040(35–45)32731(33–37)
P trend d 0.610.660.45
Retinol (IU)
≤1487.235(33–38)7541(37–51)30232(29–34)
>1,487.2–2,616.035(32–37)7939(36–48)29832(34–45)
>2,616.0–5,308.035(34–38)7341(36–48)30432(35–47)
>5,308.035(32–37)5641(32–43)32132(35–47)
P trend d 0.350.610.5
Carotene (IU)
≤6796.735(32–37)10640(32–44)27131(29–33)
>6796.7–10,492.436(33–38)7241(37–49)30533(31–35)
>10,492.4–15,998.735(33–37)5042(33–45)32732(30–35)
>15,998.734(32–37)5538(36–48)32231(29–33)
P trend d 0.770.560.77
Vitamin C (mg)
≤146.634(32–38)9638(33–44)28131(29–33)
>146.6–217.336(33–37)7840(34–45)29933(31–36)
>217.3–385.236(33–37)4341(38–50)33433(31–35)
>385.235(33–38)6643(35–49)31132(30–34)
P trend d 0.230.030.68
Vitamin D (IU)
≤188.735(33–38)8640(34–45)29132(30–35)
>188.7–328.434(33–37)7540(35–46)30231(29–33)
>328.4–562.835(33–38)7641(35–46)30132(30–35)
>562.835(32–37)4642(35–48)33132(30–34)
P trend d 0.680.550.96
Vitamin E (IU)
≤6.935(32–37)8738(33–46)29033(30–35)
>6.9–12.434(33–38)7739(34–47)30031(29–33)
>12.4–51.735(33–38)7543(34–44)30232(29–34)
>51.736(32–37)4442(36–47)33332(30–35)
P trend d 0.20.050.88
Vitamin B12 (mg)
≤5.234(34–38)6340(38–50)31431(29–33)
>5.2–7.134(33–38)8838(34–46)28931(29–34)
>7.1–12.136(32–37)8242(33–43)29533(31–35)
>12.136(35–37)5043(36–49)32733(30–35)
P trend d <0.010.140.03
Folate (mg)
≤294.735(34–38)9340(38–50)28432(29–34)
>294.7–378.134(33–38)6140(34–46)31631(29–34)
>378.1–627.336(32–37)6742(33–43)31033(30–35)
>627.336(35–37)6241(36–49)31533(30–35)
P trend d 0.10.320.27
  • a All analyses are adjusted for caloric intake, age, age2, body mass index, WHR, physical activity, age at menarche, age at first birth and number of births combined, self-reported alcohol intake, smoking, family history of breast cancer, hormone replacement usage (all and postmenopausal women), and oral contraceptive usage (premenopausal women).

  • b Analyses for all women combined are also adjusted for menopausal status.

  • c The analyses for all women are performed on quartiles of the energy-adjusted dietary variable.

  • d Test for trend is an F test of the linear contrast.