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 are more likely to live longer than men? And how the advantage has grown as time passes? We only have partial evidence and the evidence isn't strong enough to make an unambiguous conclusion. Although we know that there are biological, psychological and environmental factors which all play a part in women's longevity more than males, it isn't clear how much each one contributes.

We are aware that women live longer than males, regardless of weight. However this isn't because of certain biological factors have changed. What are these new factors? 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 over the line of parity diagonally. This means that a newborn girl in all countries can be expected to live for longer than her younger brother.

This chart is interesting in that it shows that, while the advantage for women exists everywhere, the difference between countries is huge. In Russia women have an average of 10 years more than men; in Bhutan the difference is less than half one year.

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The advantage for women in life expectancy was much lower in countries with higher incomes as compared to the present.
Let's examine how the advantage of women in life expectancy has changed over time. The next chart plots male and female life expectancies at birth in the US from 1790 to 2014. Two distinct features stand out.

First, there's an upward trend. as well as women in the US live much, http://www.jurisware.com/w/index.php/User:HannahSmithers much longer than they did a century ago. This is in line with historical increases in life expectancy everywhere in the world.

And second, there is an ever-widening gap: female advantage in terms of life expectancy used to be extremely small however, it has increased significantly over the last century.

You can confirm that these principles are also applicable to other countries with data by selecting the "Change country" option in the chart. This includes the UK, France, and Sweden.