We can manipulate Ageing to live longer

Why do we age?

There are hypotheses that damage to DNA probably affects cell renewal in stem cells, which in turn prevents repair in the body and contributes to loss of viability. Then there is the free radicals theory of ageing: the idea that as mitochondria in our cells burn energy with oxygen, it generates very highly reactive compounds, which creates damaging oxidative stress, which in turn accumulates with age and causes ageing. 
There are also things like telomeres, the tips of chromosomes that shorten with cell division. But because this also occurs with age (and is linked to cancer risk), people have said this drives the process of ageing."The thing with ageing, of course, is that it entails different levels – molecular, cellular, hormonal and physiological – different organs and different systems in the body, which makes it very complex and relatively difficult to study. We actually don't know much about ageing in the sense of its mechanisms – how and why we age. And what drives the process of ageing is still relatively poorly understood. If you look at it evolutionarily, our lifespan has only recently been so long."