Unproven dietary cancer treatments

Complementary therapies are treatments that may help you cope better with side effects such as pain. They may also increase your sense of control over what is happening to you, decrease your stress and anxiety, and improve your mood. There are many types of complementary therapies, such as herbal medicine, acupuncture, massage, relaxation and meditation.

By contrast, alternative therapies, which include unproven diets, are often defined as those used instead of conventional medical treatments. These therapies may be harmful if people with cancer delay or stop using medical treatment in favour of them.

There are no special foods, diets or vitamin and mineral supplements that have been scientifically proven to cure cancer or to stop it from recurring. Unproven diets are often expensive, restrictive and repetitive. It is important to enjoy a wide variety of foods to keep you well nourished.

Many unproven dietary treatments, particularly those that cut out food groups such as meat or dairy products are likely to be low in energy (kilojoules), protein, fat, iron, calcium and zinc as well as vitamins. This can cause unwanted weight loss, tiredness and decrease your immune function. Your recovery and quality of life can improve if your diet includes adequate amounts from each food group.

Some alternative therapies can be harmful even when used in combination with conventional therapy. It is important that your doctor, dietitian, nurses and pharmacist are aware of all the treatments you are taking.

Juice therapies

Juice therapies involve using fresh fruit and vegetable juices as the main source of food. Supporters of juice therapy believe it strengthens the immune system, reduces blood pressure and helps to clean out (detoxify) the body. However, while the health benefits of fruit and vegetables are well documented, the benefits of juice therapy are not. Juice only contains a fraction of the fibre of whole fruit or vegetables. The protective effect of fruit and vegetables may be related to many factors in the whole fruit and vegetables, not just the juice. Use fresh fruit and vegetable juices as part of a varied eating plan.

For more information, or a copy of Cancer Council’s booklet Understanding Complementary Therapies, call Cancer Council Helpline 13 11 20.

The checklist below will help you assess any diet therapy you are thinking of undertaking. Is the diet likely to:

  • Exclude one or more of the basic food groups?
  • Include large amounts of specific fruits, vegetables or their juices?
  • Exclude cooked foods or limit the cooking methods allowed?
  • Exclude or limit protein foods like meat, fish and chicken?
  • Completely change the way you choose, prepare and cook your foods?
  • Result in weight loss during your cancer therapy?
  • Prevent you enjoying social occasions with family and friends?
  • Include large amounts of special supplements?
  • Cost you a lot of money and time?

If you answer yes to any of these questions, the diet could affect your recovery and compromise your health. Some eating patterns and nutrition supplements or pills can be harmful and may interfere with the success of your medical treatment. Before radically changing the foods you eat, or taking vitamin/mineral pills or herbal remedies talk to your doctor or dietitian.

This information was last reviewed in June 2013

This information has been reviewed by: Jenelle Loeliger, Head – Nutrition Department, Peter MacCallum Cancer Centre, VIC; Kate Aigner, Cancer Information Consultant, Cancer Council Helpline ACT; Ian Anderson, Consumer; Anna Boltong, PhD Candidate (Dietitian), Department of Cancer Experiences Research, Peter MacCallum Cancer Centre, VIC; Clare Hughes, Nutrition Program Manager, Cancer Council NSW; Bridget Kehoe, Public Health Coordinator (Nutrition and Physical Activity), Cancer Council QLD; Steve Pratt, Nutrition and Physical Activity Manager, Cancer Council WA; and Roswitha Stegmann, Helpline Nurse, Cancer Council WA.

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