It's natural to assume that bearing and caring for children must wear heavily on mothers. But counterintuitive new research findings suggest that women with more kids actually age slower than their childfree counterparts. From an evolutionary perspective, mothers of several grown children are sort of done with their purpose in life, but their DNA actually seems to be in better shape. Is this the secret of hot moms everywhere?
The research team, from Simon Fraser University in Canada, looked at 75 women in Guatemala at two points 13 years apart. They found that, in general, women who had given birth to more surviving children had longer telomeres at the end of each strand of their DNA. Since telomeres are involved in DNA replicating successfully and shortening telomeres are a sign of aging-related problems, the researchers' discovery implies that the mothers of more children were aging slower physiologically.
A few caveats, though. Since the study looked at women who already have children, we know that those women are (or were) definitely fertile. The longer telomeres could be a pre-existing factor in fertility, maybe even a partial cause of it, rather than childbearing itself being responsible for any telomere-lengthening effect. Additionally, in this Guatemalan community, mothers of many children routinely receive intense support from their families and communities over their lifetimes. That may have more of a mitigating impact on aging than pregnancy and childbirth.
A larger study group would be required to figure out the direction of causation and the effects of social support, perhaps one including surrogate mothers who gave birth to several children but who didn't rear them, mothers of non-surviving children, and women who raised several children as underprivileged single moms. That would help to tease apart the complicated relationships amongst reproducing, environment, pre-existing genetics, and aging.
Of course, even if the study's findings are accurate, this isn't exactly a knock-down argument for beginning to pop out babies today, and there are plenty of reasons not to have kids. But if you are going to have kids anyways, it's nice to know that they might help to keep you young. With more mothers working outside the home than ever before, retirement ages increasing (if you even still manage to retire at all), and adolescence (i.e. parental dependence) dragging into adult children's 20s, goodness knows mothers will need all the good health and energy they can get later in life.