Why do women live longer than men?

It's no secret that Women usually live longer than men. The question is how do they do it? Well now, Stanford University scientists may have some answers, EyeOpener explains.

They put out a study published in Cell Stem Cell, showing that estrogen has increased blood stem cells in female mice, and even helped them regenerate brain stem cells faster than male mice. Plus, male mice lived longer when they were given estrogen supplements.

So estrogen could have something to do with longevity. But something else might be a major factor that give ladies the advantage.

Thomas Perls from Boston University School of Medicine notes that women are more prone to have an iron deficiency because of their periods.

Dr Perls says that iron helps produce oxygen free radicals. Oxygen free radicals, while awesome at fighting infections, also contribute to aging by damaging cell membranes. So if you got less iron, there's less free radicals, and your cells all over your body might age slower.

Not to mention all the lifestyle reasons. Dr. Marianne Legato from Columbia University sites that women are less likely to be daredevils, usually take better care of their heath, and have stronger social networks.

When you look at the oldest people in the world, the top 10 are all ladies, and no dude has made it to 117 yet.

The CDC even says that a girl born in 2012 can expect to live to about 81 years old, and a boy, born the same year, is looking at around 76 years on the planet.

Speaking of long lives, did you know these British sisters are the world's oldest siblings? Combined, they have lived a whopping 391 years!

Take a look at some of the oldest people ever: