Research

Hormonal

Vitamin D supplementation (1100 IU/day) combined with Calcium (1400-1500 mg/day) reduces the relative risk of cancer incidence by ~60% in postmenopausal women.

Postmenopausal women may consider 1100 IU of Vitamin D3 and 1400-1500 mg of Calcium daily, as one major trial showed a 60% reduction in cancer risk. However, consult your doctor, as causality is not fully proven and individual needs vary.

ModerateSupportsMEDIUM confidence
a population-based, double-blind, randomized placebo-controlled trial of 4 years duration with more than thousand postmenopausal women, whose principal secondary outcome was cancer incidence, showed that the supplementation with calcium (1400–1500 mg/day) and vitamin D3 (1100 IU/day) reduced the relative risk (RR) of cancer by ~60% (p < 0.01).
Matthias G. Wacker et al. · Nutrients · 2013

Why this rating

Based on one major RCT and ecological studies; causality is not fully proven and confounding factors (obesity, activity) exist.

Source

Vitamin D — Effects on Skeletal and Extraskeletal Health and the Need for Supplementation

Matthias G. Wacker et al. · Nutrients · 2013

DOI 10.3390/nu5010111

narrative_reviewCited 731×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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