The findings, published in the academic journal, Gut, are based on 183 men and women with the bowel disease, from two district hospitals in the north east of England.
At the time of the study, symptoms of frequency, urgency, and bloody stools had subsided, and the patients were well. On average, patients had had their disease for six years.
Dietary intake was assessed using a food frequency questionnaire, listing 107 types of food commonly eaten in the UK, and a food atlas, showing portion size. A food table was used to indicate the sulphur content of the foods consumed.
During the year of monitoring, just over half the patients relapsed (52%). Those who ate the most meat (100g or more a day)* were three times as likely to relapse as those who ate the least (50g a day) If this was red and/or processed meat the risk was even greater: these patients were five times as likely to relapse. A high intake of animal protein in general?meat , fish, eggs¯tripled the risk.
Those who drank the most alcohol (more than 2 units a day) were also almost three times as likely to relapse compared with those who drank the least (less than 1 unit a day).
Risk of relapse was not associated with high intake of milk and dairy products, and high levels of dietary fibre did not seem to ward off the risk of relapse either.
When the food constituents were assessed, high intakes of sulphur and sulphate were associated with relapse, which could explain the link with red meat and alcohol, say the authors.
The main sources of dietary sulphur are the sulphur amino acids, found in high protein foods, such as red meat, cheese, milk, nuts and eggs, and sulphate. Sulphate is found in brassica vegetables, such as broccoli, and is used as a preservative in processed foods, especially bread, beer, sausages, and dried fruit. Many alcoholic drinks also contain sulphate.
A high sulphur diet produces hydrogen sulphide, which damages the inner lining of the bowel, making it more 'leaky' and increasing cell turnover, say the authors.
*These figures are not in the paper, but have been supplied by the lead author.
Dr Mark Welfare, University of Newcastle, North Tyneside Hospital, Tyne and Wear, UK. Tel: +44 (0)191 293 2574 Email: email@example.com
JOURNAL REF: Influence of dietary factors on the clinical course of ulcerative colitis: a prospective cohort study, Gut 2004; 53: 1479-84. See the paper in full at this link: http://press.psprings.co.uk/gut/september/1479_gt24828.pdf
This press release was issued by the British Medical Association + 44 (0) 20 7383 6174
published on: 14th September 2004