05/08/2025
Breastfeeding has been shown to provide protective effects against certain cancers, both in mothers and infants, based on large-scale epidemiological studies.
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✅ In Mothers:
1. Breast Cancer
Protective Effect: Yes
Estimated Risk Reduction:
4.3% reduction in risk per 12 months of breastfeeding (combined across all children), according to a large pooled analysis by Collaborative Group on Hormonal Factors in Breast Cancer (Lancet, 2002).
Each birth also independently reduces risk by 7%.
Mechanism:
Suppression of ovulation reduces lifetime estrogen exposure.
Promotes differentiation of breast cells, reducing their vulnerability to carcinogenesis.