D: It's time to go again to the A Moment of Science mailbag. A listener writes:
Dear A Moment of Science,
I've heard that women, on average, tend to live longer than men. Is this true? And if so, why?
Y: Great question! First, it is true. According to lots of evidence, women do live longer than men, on average. In fact, humans are the only species for which this appears to be true under all conditions. For example, women comprise ninety percent of people who live to be 110 years old or older. Iceland provides another example. From the mid 1800s to the early 1900s, the country experienced famine, flooding, volcanic eruptions, and disease outbreak. But no matter the deprivations, census data shows that women still tended to outlive men.
D: As for why women tend to live longer than men, that's a mystery. It could be due to hormones such as testosterone, which men have more of than women. Women's greater longevity could also be linked to differences in male and female immune systems, or responses to free radical molecules.Y: But strangely, although women may live longer than men, they also tend to be less healthy during their adult lives. For example, women are more likely to suffer from joint and bone problems, including osteoarthritis, osteoporosis, and back pain.