Women live longer than men, even in the worst circumstances

A new study from Duke University shows that women are more likely to survive times of crisis than men. Women now live up to 10 years longer than men, and the new research suggests that this is also the case during the worst of circumstances.

The experts found that, in times of adversity, newborn girls are more likely to survive than boys. The researchers say that the fact that women have an advantage over men even in infancy, which is before behavioral differences between the sexes have developed, suggests that the explanation must be biological.

The research team analyzed mortality data for people who lost their lives to famine, disease, or other crises dating back around 250 years. The data covered seven different populations of individuals whose life expectancy was only 20 years or less, including slaves in Trinidad and the United States in the early 1800s and famine victims in Sweden.

Freed American slaves who were relocated to Liberia in the 1800s experienced the highest mortality rates ever recorded. More than 40 percent died during their first year, which was most likely the result of exposure to tropical diseases.

In the 1840s, a potato blight caused widespread crop failure in Ireland and life expectancy dropped by more than 15 years.

The study revealed that women live longer than men by an average of 6 months to 4 years even when mortality rates are very high for both sexes. For example, girls born during a famine that struck the Ukraine in 1933 lived 50 percent longer than boys.

When the researchers categorized their results by age group, they found that most of the female survival advantage comes from differences in infant mortality. Newborn girls are more resilient than newborn boys.

The findings indicate that the life expectancy gender gap cannot be fully attributed to social differences between the sexes, such as violence and risky behavior. The female advantage in times of crisis may be due primarily to biological factors such as genetics or hormones.

Estrogens, for example, have been shown to strengthen the body’s immunity to infectious disease.

“Our results add another piece to the puzzle of gender differences in survival,” said the study authors.

The research team was led by Virginia Zarulli, an assistant professor at the University of Southern Denmark. The study is published in Proceedings of the National Academy of Sciences.

—

By Chrissy Sexton, Earth.com Staff Writer