Broccoli may play an important role in blocking a key stage in the development of the inflammatory bowel disease (IBD), Crohn’s disease, the results of a new study indicate.
There are two types of IBD – Crohn’s and ulcerative colitis. They can be difficult to tell apart as in both diseases, there is inflammation and damage to the intestine wall in the form of lesions or sores that often bleed easily.
However, with Crohn’s disease, symptoms can be more severe and any part of the intestine can be injured, although problems are most common in the small intestine or ileum near the entrance to the large intestine.
According to UK researchers, the causes of Crohn’s disease are thought to be a mixture of genetic and environmental factors, one of which is very likely to be diet. The disease is significantly less common in developing countries, where fibrous fruit and vegetables, such as broccoli, are dietary staples, and its incidence has recently risen rapidly in Japan, in tandem with the increasing adoption of a more Westernised diet there.
One of the key stages in the development of Crohn’s is invasion of the cells lining the bowel by bacteria, particularly a ‘sticky’ type of E. coli, so the researchers looked at dietary agents that might influence this process.
They cultured M (microfold) cells, which are bowel lining cells that are the common entry point for invading bacteria that cause diarrhoea, in a process known as translocation.
The researchers from Liverpool then tested whether preparations of plant soluble fibres prepared from leeks, apples, broccoli and plantains, and the fat emulsifiers polysorbate 60 and 80, commonly used in processed food manufacturing, could alter E. coli translocation across M cells.
They found that broccoli fibres reduced translocation of E. coli by between 45% and 82%, while leek and apple fibres had no noticeable impact. By contrast, the emulsifier polysorbate 80 substantially increased translocation.
These results were then confirmed in tissue samples taken from patients undergoing surgery for other gut disorders.
The findings suggest that supplementing the diet with broccoli or plantain fibres might prevent relapse of Crohn’s disease, the researchers said.
Details of these findings are published in the journal, Gut.