Tuesday, February 16, 1999 Published at 12:52 GMT
Cancer experts back fibre
Cancer experts still back a high-fibre diet
Eating lots of fibre does protect against bowel cancer, despite reports to the contrary, say leading experts.
The Cancer Research Campaign (CRC) says cancer specialists from around the world still believe a high fibre, low fat, low calorie diet can reduce bowel cancer - the second deadliest cancer in the UK.
A US study of nurses published last month suggested fibre had no effect on bowel cancer rates.
But according to Professor Gordon McVie of the CRC most research is still positive about the beneficial effects and one recent study shows that it may even help prevent breast cancer.
He said government recommendations that people should eat 18 grams of fibre a day were still valid, but only 20% of the population are eating the right amount.
The total budget for anti-cancer drugs is less than the NHS budget for laxatives, said Professor McVie.
"There is a lot of confusion about the diet message," he stated. "It is quite important that we in the cancer business are still saying the same thing."
He said there were at least 39 major studies on bowel cancer and fibre. Twenty-five showed fibre had a positive effect on cancer, 11 showed no significant difference and three showed a negative impact.
The US study sat on the fence, but Professor McVie said it did not contain a representative sample of the population.
Only a small number of the 90,000 middle-aged nurses studied developed cancer.
Moreover, statistics showed that it is not until late middle age that the numbers of bowel cancer cases start to soar.
The CRC is backing a huge European study of diet and cancer which involves over 400,000 men and women in nine European countries.
The high mortality figures are because it is difficult to catch in the early stages.
Despite the plethora of fibre studies, no-one knows exactly how it works on cancer.
There are several theories, including one suggesting that one chemical in the product helps re-establish a mechanism in cells which allows cancerous cells to commit suicide.
The fact that fibre reduces constipation could also have a positive impact by ensuring harmful substances are removed from the digestive system quickly.
And it may be not just bowel cancer which fibre affects.
A recent study published in the European Journal of Cancer Prevention suggests fibre, particularly wheatbran fibre, can protect against breast cancer.
It shows women are on average a third less likely to have breast cancer if they eat a high fibre diet.
The effects are improved if women do not overeat in childhood and take plenty of exercise.