An analysis of 303,196 subjects enrolled the UK Biobank, a longitudinal study since 2006, found men and women with children were both faster and more accurate in a "Pairs Matching" visual memory task used as a of proxy relative brain age than those without kids.
Since it impacted men as well as women, the brain-enhancing effect was not due to pregnancy, but may instead be that parents engage in lifestyle changes. Many put on a little weight but many also engage in more community activities, binge-drink less, and eat healthier.
The difference in the subset of 13,584 who had brain scans (to quantify structural changes and natural tissue loss) was noticeable. Men with at least two children performed the brain task at a level at least 0.6 years younger than their childless peers. The authors say that is correlated to the brain benefit of exercising 2.5 hours a week.
Exercise has other benefits besides the brain, don't stop lifting weights and just have more kids, but the effects compound. And kids have to listen to your jokes.
Citation: Kaida Ning , Lu Zhao, Meredith Franklin, Will Matloff, Ishaan Batta, Nibal Arzouni, Fengzhu Sun , Arthur W Toga . Parity is associated with cognitive function and brain age in both females and males. Sci Rep. 2020 Apr 8;10(1):6100. doi: 10.1038/s41598-020-63014-7. PMID: 32269255; PMCID: PMC7142076.
