WHAT IS AGEING?
In relation to human beings.

The big question is; what is ageing and how and why does it happen? We all know people who are "young for their age" (maturing like fine wine) and others who look, and say they feel, "much older than their years" (a bit ragged and wearing out like old clothes). It is only by asking, "What is ageing?" And taking time to try and understand the answers we get, that we put ourselves in a position to make the informed choices that will dramatically improve our chances of being in the former group and not the latter. So, what is ageing?

Prof. Thomas Kirkwood is a Professor of Medicine whose research interests are; Evolution and genetics of ageing. After years of studying ageing by focusing on our bodies' cells Prof. Kirkwood realised that we age because only our genes need to survive.

He realised that life is inherently risky, although it was far riskier for our distant ancestors than it is today. At any time our ancient ancestors might have been overwhelmed by infection, illness, accident or starvation making life a very tenuous affair. As a result, to ensure the survival of the species he believes that through nature and evolution a situation has developed where our genes benefit from bodily protection mechanisms of the highest level, since our genes are all that need to be passed to the next generation. Evolution has invested less in the bodily protection mechanisms for the rest of the cells that make us (termed the somatic cells), since the somatic cells are needed only for as long as we manage to stay alive. I find it hard to come to terms with natures view, that apart from my genes, everything about me is cruelly disposable. But Hey! It makes sense, we need to make room for the new models that make up the next generation.

Although the protection mechanisms or survival programming for the somatic cells are not of the highest level, they are still pretty awesome when you think how our bodies' cells are replaced by a programme of continuous regeneration and repair.

Prof. Kirkwood's research indicates that over our lifetime our somatic cells develop more and more tiny faults through errors in the repair process, the result of this is what we might recognise as ageing when we look in the mirror. He refers to this buildup of tiny cellular faults as the by-products of the chemistry of life and reminds us that the buildup would be much faster without the protection of our fantastic cellular repair systems. This buildup of faults does however lead to age-related diseases and frailty.

Prof. Kirkwood's theory represents good news. He says "Maximum life span is not clock-driven but malleable, e.g.through modifying exposure to damage or enhancing somatic maintenance functions." By studying how to, and supporting the repair and maintenance functions of the body's cells, a lot can be done to improve how we age and keep at bay the conditions which can disable us and undermine the quality of our later life.

This indicates that ageing is a biological process we cannot stop, but by making informed decisions and acting on them we can influence how it progresses.

Prof. Thomas Kirkwood is Professor of Medicine at the Policy, Ethics, and Life Sciences Research Centre, Newcastle University.