Women who #breastfeed exhibit #cognitive benefits after age 50

Background and objectives
Women who breastfeed may experience long-term benefits for their health in addition to the more widely-appreciated effects on the breastfed child. Breastfeeding may induce long-term effects on biopsychosocial systems implicated in brain health. Also, due to diminished breastfeeding in the post-industrial era, it is important to understand the lifespan implications of breastfeeding for surmising maternal phenotypes in our species’ collective past. Here, we assess how women’s breastfeeding history relates to post-menopausal cognitive performance.

A convenience sample of Southern California women age 50+ was recruited via two clinical trials, completed a comprehensive neuropsychological test battery and answered a questionnaire about reproductive life-history. General linear models examined whether cognitive domain scores were associated with breastfeeding in depressed and non-depressed women, controlling for age, education, and ethnicity.

Women who breastfed exhibited superior performance in the domains of Learning, Delayed Recall, Executive Functioning and Processing Speed compared to women who did not breastfeed (p-values 0.0003-0.015). These four domains remained significant in analyses limited to non-depressed and parous subsets of the cohort. Among those depressed, only Executive Functioning and Processing Speed were positively associated with breastfeeding.

Conclusions and implications
We add to the growing list of lifespan health correlates of breastfeeding for women’s health, such as lower risk of type-2 diabetes, cardiovascular disease, and breast cancer. We surmise that women’s post-menopausal cognitive competence may have been greater in past environments in which breastfeeding was more prevalent, bolstering the possibility that post-menopausal longevity may have been adaptive across human evolutionary history.

Lay Summary
Breastfeeding may affect women’s cognitive performance. Breastfeeding’s biological effects and psychosocial effects, such as improved stress regulation, could exert long-term benefits for the mother’s brain. We found that women who breastfed performed better on a series of cognitive tests in later life compared to women who did not breastfeed.