Prostate cancer fighters

Men at risk of prostate cancer can do something about it themselves by cooking with foods that are rich in potential anti-cancer agents, an academic nutritionist said this week.

Certain foods cooked in special recipes could have a significant effect on lowering the risk of developing cancer of the prostate, said Margaret Rayman, professor of nutritional medicine at the University of Surrey, citing broccoli, pak choi, rocket and watercress as examples.

There is convincing evidence to suggest that diet plays a leading role in determining whether men develop prostate cancer, and modifying the way food is cooked could help to lower the risk, Rayman said.

"There is a growing body of scientific evidence that strongly suggests that diets rich in certain foods can help to prevent this disease or its spread," she told the British Science Festival.

"There is evidence that eating certain foods in the appropriate quantity and with sufficient frequency can reduce the risk of prostate cancer or slow its progression."

By preparing or cooking food in ways that do not destroy any natural anti-cancer ingredients, men with a family history of prostate cancer, or who are in remission, can also benefit from the psychological boost that cooking can give, she said.

"Consciously making changes to diet and lifestyle is associated with a positive, optimistic attitude and a feeling of being in control," said Rayman. "This has long been known to improve the immune system and can therefore have a direct effect on how disease progresses."

Allium vegetables, such as onion and garlic, are best prepared by leaving them for 10 minutes after chopping them up before heating them in a pan, she suggested. This allows an enzyme called alliinase, which is destroyed by heating, to work on sulphur compounds in the vegetables and turn them into diallyl sulphides, which are known to have an anti-cancer effect and are not destroyed by heat.

Cruciferous vegetables such as broccoli, pak choi, rocket and watercress release an enzyme called myrosinase when chopped, bruised or chewed, which reacts with natural substances called glucosinolates to convert them into isothiocyanates and indoles - both of which have anti-cancer properties.

Myrosinase is also destroyed by heating, so eating these vegetables raw, or steaming them lightly and using the waste water for gravy, can still be beneficial because certain bacteria that live in the gut can produce myrosinase to act on the glucosinolates that pass through the digestive system.

"Prostate cancer is often slow to develop and spread, and so strategies that can influence its progression have considerable potential. For those living with the condition, a controlled diet may provide the only means of active treatment," Rayman said.

"Some of the evidence is very flimsy... [but] on the other hand the principle is that there is nothing here that is going to do you any harm. I wouldn't say that this will definitely make a difference, but there is definitely evidence that suggests that it may make a difference and it gives you the option to do something."

Prostate protection: What you should eat

Breakfast: Porridge with oats and soya milk; raspberry and pomegranate compote (good source of polyphenols, soya and vitamin E).

Lunch: Pea and mint soup; sardines, chickpea and avocado salad (high in legumes, alliums and fish oil).

Dinner: Chicken kebabs and peanut sauce with broccoli; tomato and basil salad; redberry and nut crumble (rich in lycopene, selenium, allium and legumes). - The Independent

• This article was originally published on page 12 of The Mercury on September 21, 2009