On average, women live 5-10 longer years than men. But this is just an average: not all women live longer.
Women generally have fewer heart problems than men. Some researchers this is down to hormonal differences between men and women. A hormone called estridiol, which is releasaed during menstruation, can strengthen the heart over the lifecourse. Oestrogen has also been found to lower cholesterol levels, which again influences risk of heart disease.
There might also be some genetic factors. In terms of sex chromosomes, women have 2 X chromosomes, men have 1 X and 1 Y. It’s the Y chromosome that has the instructions for making an embryo into a “boy”, but it doesn’t have many other genes. So women have two copies of all the genes on the X chromosome, while men only have 1. If some of these genes are invloved in living longer, then women may have an advantage if they have two different copies, as opposed to the single one that men do.
Lifestyle factors that have an influence too. This may be over-generalising slightly, but men tend to drink and smoke more on average, and many have poorer diets.
So ultimately, I’m going to fall back on my default explanation for everything – “it’s probably due a mixture of genetic and environmental factors”. Which is really just a way of saying “We don’t know for sure. Yet.”. Always “yet”. We’re still looking. 😀
There is a view that the cells of mens bodies are not genetically programmed to live as long as womens. Female animals also tend to live longer than male ones and if you neuter animals then they also live longer. Ageing (as Andy said) is probably to do with genetics, hormones and enviromental factors. Men generally are more susceptible to, and develop, age related diseases (like cardiovascular disease and strokes) 10 years earlier than women.
In terms of evolution females probably live for longer since they are responsible, at least in mammals, for the care of the young. In a reproductive sense it makes sense for women to live longer.
The best thing we can do is take care of our bodies and try not to cause too much damage to our cells. 🙂