Research
Mixed
Daily supplementation with 1000 mg elemental calcium and 400 IU vitamin D3 does not reduce the incidence of invasive breast cancer in postmenopausal women.
For postmenopausal women, taking 1000 mg of calcium and 400 IU of vitamin D3 daily will not reduce the risk of developing invasive breast cancer. While these supplements are important for bone health, they should not be used as a strategy for breast cancer prevention.
StrongRefutesHIGH confidence
Calcium and vitamin D supplementation did not reduce invasive breast cancer incidence in postmenopausal women.
Why this rating
Large-scale, randomized, double-blind, placebo-controlled clinical trial (N=36,282) with long follow-up (mean 7 years).
Source
Calcium Plus Vitamin D Supplementation and the Risk of Breast Cancer
Rowan T. Chlebowski et al. · JNCI Journal of the National Cancer Institute · 2008
rct · n=36282Cited 424×
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