Maintain a healthy weight

Excess weight appears to increase the risk of several types of cancer, including those of the oesophagus, colon, breast, kidney and womb. Experience shows that a diet based on whole, natural and unprocessed foods such a meat, fish, eggs, fruits, vegetables, beans, lentils and nuts is usually the way forward for those seeking to achieve a healthy body weight.

Be active

Physical activity has been associated with relative protection from colon cancer and probably breast cancer, too. While it is not known how much activity is necessary for benefit here, half an hour's daily exercise can make a difference.

Eat plenty of fruit and vegetables

Fruit and vegetables are rich in vitamins, minerals, fibre and plant substances known as phytochemicals, many of which may have cancer-protective effects. A good intake of fruit and vegetables has been associated with a reduced risk of a range on cancers, including those of the mouth, oesophagus, stomach and colon. Five 80 gram servings of fruits and vegetables each day seems to be the amount needed for optimum protection. Fruits that have been singled out for particular anti-cancer properties include all types of berries such as blueberries, strawberries and raspberries. Vegetables that are similarly lauded include broccoli, Brussels sprouts and cabbage.

Limit your alcohol intake

Relatively high alcohol intakes are associated with an increased risk of several cancers including those of the mouth, larynx, oesophagus and liver. And small amounts of alcohol seems to increase breast cancer risk. Drinkers would do well to balance their alcohol consumption with plenty of water.

Ensure a good intake of folic acid

Research suggests that alcohol's ability to increase cancer risk can be counteracted by a good intake of the nutrient folate Also, higher folate intakes are associated with a reduced risk of other cancers, including colon cancer and ovarian cancer, too. Good sources of folate include oranges, green leafy vegetables, asparagus and cantaloupe melon. Those looking for additional protection (particularly women drinkers) might do well to supplement with 400 mcg of folic acid per day.

Ensure a good intake of selenium

Selenium is an antioxidant nutrient, which means it helps to quench rogue, damaging chemical entities called free radicals that are heavily implicated in the processes that cause cancer. In one study, supplementation with 200 mcg of selenium per day was associated with a halving in the risk of dying from cancer. Brazil nuts are naturally rich in selenium - three or four of these nuts will provide the body with about the same as 200 mcg selenium supplement.

Drink mineral water

Higher intakes of water have been found to be associated with a reduced risk of cancers of the colon and bladder. However, not all waters are as equal as others. Studies have found that tap water is associated with an increased risk of bladder and rectal cancer, the likely culprits being chlorine and related compounds. Mineral water, which is free of these chemical contaminants, is a healthier option.

Go for wholegrains

The consumption of refined carbohydrates such as white bread, white rice and pasta tends to stimulate the production of the hormone insulin and insulin-like substances that some scientists believe have cancer-causing potential. On the other hand, wholegrains (such as brown rice, oats, wholemeal bread, wholewheat pasta), tend to give rise to more tempered amounts of insulin. They are also richer in fibre and nutrients, which also may help protect against cancer.

Drink green tea

Green tea contains antioxidants known as polyphenols. One such polyphenol - epigallocatechin gallate (EGCG) - has been found to have a number of beneficial actions in the body, including an ability to help in the deactivation of cancer-causing chemicals (carcinogens). Studies have linked the drinking of green tea with very reduced risk of cancers of the breast and prostate. While green tea may help to keep the body cancer free, it's best not to have it too hot: research has linked the drinking of very hot drinks with an increased risk of cancers of the mouth, pharynx (soft palate) and oesophagus.

Get out in the light

While sun exposure may increase the risk of skin cancer, it is also believed to have health-giving properties. For instance, the action of sunlight on skin increases the formation of vitamin D, a nutrient which has cancer-protective properties. Studies have linked sunlight exposure with a reduced risk of cancer of the breast, colon, prostate, ovary, bladder, womb and oesophagus.

· Read Dr John Briffa in OM magazine every week