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. What's the main reason women have a longer life span than men? Why is this difference growing as time passes? We only have a few clues and the evidence isn't sufficient to support an absolute conclusion. We recognize that biological, behavioral and environmental factors contribute to the fact that women have longer life spans than men, but we don't know exactly how strong the relative contribution of each one of these factors is.

In spite of the precise amount of weight, we are aware that at least a portion of the reason why women live longer than men do today however not as previously, is to be due to the fact that several fundamental non-biological factors have changed. The factors changing are numerous. Some are well known and relatively straightforward, like the fact that men smoke more often. Others are more complex. 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 women. We can see that all countries are above the diagonal parity line ; this means in all countries baby girls can expect to live for longer than a new boy.1

This graph shows that although there is a women's advantage everywhere, cross-country differences can be substantial. In Russia women are 10 years older than men. In Bhutan the gap is just half each year.

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The female advantage in life expectancy was much lower in developed countries than it is now.
Let's examine how the female longevity advantage has changed in the course of time. The following chart shows the male and female life expectancy when they were born in the US between 1790 to 2014. Two points stand out.

There is an upward trend. Both genders living in America are living longer than they used to 100 years ago. This is in line with historical increases in life expectancy everywhere in the world.

And second, there is a widening gap: The female advantage in terms of life expectancy used to be very small, but it grew substantially in the past century.

You can verify that these points are also applicable to other countries that have data by clicking the "Change country" option on the chart. This includes the UK, France, ماذا يحدث بين الزوجين في الحمام بالصور (simply click glorynote.com) and Sweden.