Fish oil may really be an 'elixir of youth'
Fish oil may really be an “elixir of youth" because of its effects on our biological ageing, according to a new study.
By Kate Devlin, Medical Correspondent
20 Jan 2010
Fatty acids found in fish such as salmon, mackerel or sardines have long been known to protect against conditions like heart disease.
Because of the health benefits official guidelines recommend eating at least two portions of oily fish a week, but many people eat far less.
Now scientists believe that they have uncovered the reason why fish oil is so good for us.
The discovery, made in a group of heart patients, could help confirm many of the claims made about the benefits of the fatty acids, called omega-3 fatty acids.
Researchers found that they help guard a protective ‘cap’ within cells, which helps to determine how long they will live.
Studies have also suggested that fatty acids can increase the chances of survival after suffering a heart attack, reduce the mental decline associated with old age and help prevent changes in the eye that can lead to blindness.
Tests on rats have shown that they live around a third longer if they are given a diet high in omega-3 fatty acids.
"These findings raise the possibility that omega-3 fatty acids may protect against cellular ageing in patients with coronary heart disease," said Dr Ramin Farzaneh-Far from the University of California at San Francisco, writing in the Journal of the American Medical Association (JAMA).
Cellular ageing is thought to be linked an increased risk of developing conditions like heart disease and cancer.
Scientists are still unsure, however, whether it has any relation to other symptoms of physical ageing, such as wrinkles.
Researchers have found that the acids slow down the rate at which these caps, which protect DNA and keep it organised within a part of the cell, shorten.
Called telomeres, these ‘caps’ become shorter each time cell divides.
Too short and they can leave DNA open to damage, and even eventually cause the cell to die. This rate of shortening varies but the new research has found that it is affected by fish oil.
A study on 608 patients with heart disease shows that those with high levels of omega-3 fatty acids in their diet over five years had longer ‘caps’ than those with low levels.
A higher than average intake of fish oil cut the rate of shortening by 32 per cent, the study found.
June Davison, from the British Heart Foundation, said: "This is an interesting study which may offer a further explanation as to why a dietary intake of omega-3 fats from fish can help to protect your heart.
"It is well established that a dietary intake of omega-3 is good for heart health. Oily fish, such as salmon, mackerel or sardines, is a nutritious source of omega-3."