Cells with Longer Lives

Truth about ouselves can be a nuisance for older people and it can be easier to fantasise that we are younger than we are. Getting a balance between mental attitude and physical reality is of course important, as we’ve said before. There is a sense in which we need to defy the ageing process, and shake our fist at it. But scientists say that every time a cell multiplies to make two new cells, special zones at the ends of its chromosomes, called telomeres, become shorter. Once the telomeres reach a certain length, the cell stops dividing and eventually dies. The only cells to escape this fate are those that divide to make eggs and sperm. In these cells, a substance called telomerase builds the telomeres up again, so they remain the same length.

Scientists are looking for ways to avoid, or even repair, the damage that causes ageing. As we all know, a healthy lifestyle can help you feel younger and fitter for longer. Apparently even people in their 90s can improve their muscle strength through regular exercise. Most research on ageing – of which there is a great deal-aims to improve our health and quality of life as we grow old, not make us live forever.

Now there is a new element in the pursuit of a good style of life for older people. The American Journal of Clinical Nutrition has published a study which claims that for the first time it has been possible to demonstrate that people with higher levels of vitamin D age more slowly than those with lower levels. Moreover they are likely to be more protected against age-related illnesses such as heart disease and cancer. Scientists at King’s College London have similarly found that amongst the 2,160 women who were part of a research project, those with higher vitamin D levels had significantly longer telemores, equivalent to five years of normal ageing.

Sunshine increases our Vitamin D levels. But, as the American study points out, the same sunshine ages our skin and increases the risk of skin cancer. Nothing is simple!! Apparently health guidelines recommend a daily intake of between 200 and 600 international units of vitamin D, the higher level for the over-70’s. (Another caution – too much vitamin D is bad for you! It can cause nausea, weakness and kidney damage)

B.R.