Everywhere in the world women live longer than men - but this was not always the case. The available data from rich countries shows that women didn't live longer than men in the 19th century. Why do women live longer than men, and why is this difference growing over time? We only have partial evidence and the evidence is not strong enough to make an absolute conclusion. We know that biological, behavioral and environmental factors all play a role in the fact that women have longer life spans than men, however, we aren't sure how strong the relative contribution of each factor is.

We have learned that women are living longer than males, regardless of weight. However this is not due to the fact that certain non-biological factors have changed. What are these factors that have changed? Some are well known and relatively straightforward, like the fact that men smoke more often. Other are more complicated. For example, there is evidence that in rich countries the female advantage increased in part because infectious diseases used to affect women disproportionately a century ago, so advances in medicine that reduced the long-term health burden from infectious diseases, especially for survivors, ended up raising women's longevity disproportionately.

Everywhere in the world women tend to live longer than men
The first chart below shows life expectancy at birth for men and العاب زوجية women. We can see that every country is over the line of parity diagonally. This implies that a baby girl in every country can be expected to live for longer than her younger brother.

It is interesting to note that, while the advantage for women exists across all countries, the global differences are significant. In Russia women live 10 years longer than men. In Bhutan, the difference is less than half a calendar year.

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In wealthy countries, the female advantage in longevity used to be smaller
Let's examine how the female longevity advantage has changed in the course of time. The next chart plots the male and female lifespans at birth in the US during the time period between 1790 and 2014. Two things stand out.

The first is that there is an upward trend. Men as well as women in the US are living much, much longer today than a century ago. This is in line with historical increases in life expectancy everywhere in the world.

The second is that there is an increase in the gap between men and women: female advantage in terms of life expectancy used be quite small but it increased substantially during the last century.

It is possible to verify that these are applicable to other countries with data by clicking the "Change country" option on the chart. This includes the UK, France, and Sweden.