Diet

Can diet cause cancer?

There are several well-established links between diet and the causes of cancer. In general, fresh fruit and vegetables and high-fibre diets are good for you and can reduce the risk of getting cancer. Diets based more on fish and chicken and less on red meat may also reduce the risk. A high intake of smoked food may slightly increase the risk of some cancers.

Researchers have looked at the diets of people in different parts of the world and compared them with the amount of cancer in those parts of the world. In parts of Africa where they have a high-fibre diet, bowel cancer is rare. In the USA, where they eat much less fibre, bowel cancer is more common. Other studies looking at what happens to immigrants have found that within a few generations, the immigrants are more likely to develop the same cancers as the people who are native to that country, rather than the country they came from. It is thought that diet plays a part in the development of up to a third of all cancers.

Will a change in diet alter the outlook if I have cancer?

The alternative diet therapies share a common philosophy: poor diet can help cause cancer, and so a good diet can help cure it. Unfortunately it is not so simple. There is no evidence that once you have got cancer changing your diet can treat it or reduce the risk that it may come back.

A healthy diet

Taking an interest in what you eat is a very practical way to look after yourself when you are ill, and eating well can only be helpful. Both doctors and complementary practitioners agree that a healthy diet is a good thing. The basic principles are:

• Plenty of fresh fruit and vegetables
• Foods high in fibre – wholewheat bread and grains
• More fish and chicken and less red meat
• Less fat
• Less sugar and salt
• Moderate amounts of tea, coffee and alcohol
• Take time to eat slowly, peacefully and enjoyably

These guidelines do not apply to people who have lost a lot of weight. They may need to eat whatever foods they can manage in order to get enough calories and protein. There may be times when someone with cancer wants to eat foods which are considered unhealthy, but are very enjoyable. It would be wrong to be too rigid about a healthy diet in this situation.
CancerBACUP has a further information about diet and the cancer patient, which gives advice on diet and eating problems caused by cancer or treatments.

Should I change my diet if I have cancer?

If you change your diet because you want to eat healthily, then following the basic guidelines above may be all you need to do. If you change your diet only because you think it will affect the rate of cancer growth, you may be disappointed. However, don’t feel guilty if you occasionally give yourself a treat and eat something like a chocolate mousse or fried egg and bacon, which you really enjoy. If you have lost weight it is important to eat whatever you can.

Whether or not you decide to change your diet may also be affected by your family’s views. Families who are already coping with the stress of a family member with cancer may add to the pressures on themselves by suddenly becoming vegetarians, or trying to get used to herbal teas. It is important to ask for advice but also not to forget common sense.