A healthy lifestyle may do more than simply slow the ageing process. It could actually reverse it.
Keeping physically fit, having a plant-based diet and practising stress-reduction techniques such as yoga could extend the lifespan of cells, researchers say. They studied the effect of healthy living on lengths of DNA called telomeres – tiny ‘caps’ on the ends of chromosomes that protect against the ageing process.
Just as the tips of shoelaces prevent fraying, telomeres keep chromosomes stable and prevent deterioration when the cells containing them divide. Dubbed the ‘chromosomal clock’, they shorten as we age. This process is associated with a greater risk of early death and of conditions such as heart disease, dementia, diabetes and cancers, as well as with increased vulnerability to infection.
Scientists believe the shortening process may even place an unextendable limit on the human lifespan.
The pilot study, published in The Lancet Oncology, compared two groups of men with early non-aggressive prostate cancer who had not undergone surgery or radiotherapy but were having regular checks. One group of 25 men continued without making any changes. Ten others underwent a radical lifestyle transformation supervised by doctors, nutritionists and psychologists.
Their diet was switched to one high in plant proteins, fruits, vegetables and unrefined grains while low in fat and processed carbohydrates. They were taught stress reduction techniques such as yoga and meditation, and were given counselling. They also took moderate levels of exercise, such as walking for 30 minutes, six days a week.
After five years, blood tests showed that the telomeres of the healthy-lifestyle group had lengthened by an average of 10 per cent, effectively reversing the natural ageing process. But the telomeres of the group who continued with their previous lifestyle shortened by an average of 3 per cent.
The study found no significant difference between the groups in the progress of prostate cancer.
But the scientists believe that their findings carry an important health message with wider implications.
The team’s leader, Professor Dean Ornish, from the Preventive Medicine Research Institute at the University of California in San Francisco, said: ‘The implications of this relatively small pilot study may go beyond men with prostate cancer.
‘If validated by large-scale randomised controlled trials, these comprehensive lifestyle changes may significantly reduce the risk of a wide variety of diseases and premature mortality. Our genes, and our telomeres, are a predisposition, but they are not necessarily our fate.’
Dr Lynne Cox of the University of Oxford said: ‘This new study suggests that reducing stress, improving diet and increasing exercise not only prevent telomere loss but also lead to small but significant increases in telomere length.
‘It is perhaps too soon to judge whether this increase will correlate with increased longevity or healthspan. Overall, though, the findings of this paper support the calls for adoption of and adherence to healthier lifestyles.’