The controversy over whether a high-fibre diet can prevent colon cancer continues as two new studies suggest that it has a “substantial effect” on reducing the risk of the disease.

LONDON, Friday, May 02, 2003

Two studies from the US and Europe, published in The Lancet, follow another piece of research that appeared earlier this week suggesting that, on the contrary, a high-fibre diet may not necessarily prevent bowel cancer.

In one of the latest studies, Dr Ulrike Peters and colleagues from the National Cancer Institute in Rockville, US, assessed the relationship between fibre intake and frequency of colorectal adenomas – non-malignant polyps which are often a precursor of malignant disease.

Their investigation of around 34,000 people who did not have polyps and 3,600 who had at least one adenoma in either the colon or rectum revealed that a high intake of fibre, particularly from grains, cereals and fruit, was associated with a lower risk of colorectal adenoma.

Those who were in the top 20 per cent for dietary fibre intake had a 27 per cent lower risk of adenomas compared to people in the bottom 20 per cent for fibre intake.

Appearing in the same journal, a European study reaches similar conclusions after looking at dietary fibre intake and the incidence of colorectal cancer in more than half a million people aged 25 to 70 years of age.

After an average follow-up of 4.5 years, 1,065 cases of colorectal cancer were diagnosed.

People who ate 35g of dietary fibre per day reduced their risk of colorectal cancer by as much as 40 per cent compared with those who consumed only 15g per day, according to the team of doctors from across Europe.

Professor Nick Day, who led the European study for Cancer Research UK, says, “It became clear that the amount of dietary fibre in food was inversely related to bowel cancer incidence.”

However, Professor Sheila Bingham of the Medical Research Council, which helped to fund the study, warns, “It is important for people to be aware that fibre supplements or special foods with added fibre were not studied and it should not be assumed that they have the same protective effect as foods that are naturally rich in fibre such as cereals, vegetables and fruit.”

Source: The Lancet 2003; 361: 1491-1501
© HMG Worldwide 2003