Researcher: Cold Potatoes, Beans May Prevent Colorectal Cancer

A bowl of cold mashed potatoes, cold baked beans, cold porridge or a green banana are probably a better breakfast for protecting against colorectal cancer than a high-fiber cereal, according to a leading British researcher.

Professor John Burn, director of clinical research at Cancer Researck UK and the University of Newscastle, told the British Association science festival that 500 people from 33 countries, all of whom have a genetic tendency to contract bowel cancer, have been enrolled in a trial to test this new preventive approach.

"As far as the benefits for cancer prevention are concerned, the high-fiber diet is a myth," said Burn. "It was based on a misunderstanding of the African diet and the science behind it is weak. However, it has left a lot of people eating cardboard for breakfast.

"Studies on diet from around the world show there is a beautiful relationship between the prevalence of bowel cancer and the amount of a particular sort of starch in the diet. The more of this starch, which is resistant to digestion, is eaten, the lower the incidence of bowel cancer," he said.

"Resistant" starch is present in many cooked vegetables, such as potatoes or baked beans, when they are cold, he said. When they are warm, the starch is in a jelly-like form that is easily digested. But when they cool down, the starch passes through most of the digestive-system intact and is only broken down when it reaches the gut.

"Initially there is a bit of a flatulence problem but this goes away," said Burn.

"When mashed potato goes cold it crystallises," said Burn. "So do cold baked potatoes and baked beans. In fact the same thing applies to quite a lot of the rubbish you eat. I'm talking about anything that contains carbohydrate that's not hot."

Bananas also lose their crystalline starch when they ripened, said Burn, making green bananas more protective.

"I do eat a slightly green banana every morning for breakfast," he added. "But not cold porridge, I have to say."

Other Sources: British Media, Press Association