My theory that I just made up without any research or noteworthy knowledge on the topic is that women have a slower metabolism (which is related to hormones as their muscle mass and density is lower).
The slower your metabolism and your caloric intake the less cells are replicating. When cells are being replaced there's always some degradation of genetic information involved. If you don't require much energy and thus keep your metabolism low your body is under less pressure. It's basically like a car with high mileage that has only seen constant slow long distance rides.