Red Meat Diet Damages DNA And Adds to Cancer Risk, Expert Warns
EATING red meat alters your DNA and may lead to an increased risk of developing bowel cancer, scientists said yesterday.
Chemical compounds formed while digesting meat can cause DNA to mutate and increase the likelihood of cancerous cells developing.
People who eat two portions or more of red meat a day suffer significantly more DNA damage to the cells of their colon than those who follow a largely vegetarian diet or eat red meat less than once a week.
The research, published in Cancer Research journal, found that people who eat large quantities of red or processed meat are more likely to develop cancerous tumours in their large bowel.
N-nitroso compounds are formed in the large bowel after eating red meat and can attach themselves to DNA and cause it to mutate.
Scientists compared the cells of healthy volunteers, some of them on a vegetarian diet, others eating large quantities of meat and over a period of two weeks were able to pinpoint DNA damage.
Professor David Shuker, who led the research from the Open University department of chemistry in Milton Keynes, said: "We hope to be able to develop a simple screening test so that we can spot DNA damage and advise people to change their diets by cutting down on the amount of red meat they eat before cancer develops.
"We advocate a balanced diet, not vegetarianism as there are some nutrients that are best got from meat.
"This research showed damage in healthy people so you can imagine that if someone was predisposed to bowel cancer or had an inflamed gut the effects would be more severe.
"People also have varying abilities to repair the damage to their intestines.
"I advise a balanced diet as there is not much evidence that vegetarianism lowers your risk of bowel cancer."
Eating a low-fibre diet combined with high red meat content also elevates the risk of bowel cancer because digested food and chemicals stay in the gut longer. Eating more fibre may help repair damage done to the colon.
Research by the Medical Research Council published last year showed the chance of developing colorectal cancer was a third higher in people who regularly ate more than two portions of red or processed meat a day compared to those who ate less than one portion a week.
Bowel cancer charities welcomed the research yesterday and supported the consumption of red meat in moderation.
Professor Annie Anderson, from the Centre for Public Health Nutrition Research at the University of Dundee and adviser to Bowel Cancer UK, said the rise of ready meals contributed to the trend.
She said: "We are eating more fast foods, which we know are high in calories and fat and implicated as a cause of obesity and diabetes, but such cuisine may also be the very type of meals [high in meat products and low in vegetables] that also contributes to bowel cancer risk."
The charity advises people to eat no more than 80g of meat per day, as recommended by the World Cancer Research Fund.
A spokeswoman for charity Beating Bowel Cancer said: "A third of all cancers are linked to what we eat and we must not underestimate the importance of a well-balanced diet in the prevention of bowel cancer."
Colorectal cancer is the second most common cancer found in developed countries.
More than 940,000 cases are diagnosed each year and about 492,000 people die from the illness, according to the International Agency for Cancer Research in Lyon, France.
A diet rich in fat, animal protein and refined carbohydrates and lack of exercise are risk factors for the illness.
Most cases are in people over 60 years old and about 5 per cent of them are inherited.
Health experts estimate that about 70 per cent of colorectal cancers could be prevented by changes in diet and nutrition.
Each year 35,000 people in Britain are diagnosed with bowel cancer, and 16,000 die of the disease