It was once believed that a diet high
in fibre protected against bowel cancer. It is now believed that
"resistant starch" is the substance which provides the
protection.
In populations where a large proportion of the diet
is unrefined starch, there is a much lower death rate from cancer
of the colon and other degenerative diseases.
Resistant starch - which is starch that is not easily
digested by the body - has a chemical and physical structure which
acts as a protective agent for certain bacteria (probiotics)
allowing them to survive better in the gut.
Probiotics are bacteria which are ingested in foods
like yoghurts, and they have been found to modify the physiology of
the gut. The probiotics modify the immune system promoting a
healthier body. Resistant starches allow probiotics to be present
in larger numbers thus protecting against disease.