The role of exercise and nutrition

It’s common for people with cancer to have questions about what to eat and whether to exercise during and after treatment. The right diet and exercise for you depends on the cancer type, the treatments you are having, your general health and your doctor’s advice. 

Who can help with nutrition and physical activity?

Your GP and treatment team can provide general advice, but the following experts can also help.

Exercise physiologist – An accredited exercise physiologist (AEP) has completed at least a 4-year university degree. They use exercise as medicine to help with chronic disease management and overall wellbeing.

Physiotherapist – This allied health professional has completed at least a 4-year university degree. They focus on physical rehabilitation and prevention and treatment of injuries using a variety of techniques, including exercise, massage and joint manipulation.

Dietitian – An accredited practising dietitian (APD) has completed a 4-year university degree in science, nutrition and dietetics. They modify diets to help treat disease symptoms and to get the most out of food.

Nutritionist – This term refers to both qualified nutrition scientists and naturopathic nutritionists. Some dietitians also call themselves nutritionists. Nutritionists working in the natural health industry should have at least a diploma of nutrition, or equivalent, from a university or naturopathic college.

For nutrition advice specific to cancer, speak to an accredited practising dietitian.

How exercise and a balanced diet can help

Exercise

Why it is useful – Research shows that exercise benefits most people both during and after cancer treatment.

It increases energy levels, improves sleep, reduces treatment-related muscle loss, improves bone and muscle strength, improves mobility and balance, relieves stress, and decreases fatigue, anxiety and depression.

What to expect – The Clinical Oncology Society of Australia recommends that people with cancer do:

• at least 150 minutes (2½ hours) of moderate intensity aerobic exercise or 75 minutes (1¼ hours) of vigorous intensity aerobic exercise every week
• 2–3 strength-training (resistance exercise) sessions a week to build muscle strength.

How to exercise safely

• Before taking part in any exercise program, it is important to talk to your cancer care team or GP about any precautions you should take. Ask about the amount and type of exercise that is right for you.
• Exercise professionals, such as an accredited exercise physiologist or physiotherapist, can develop an exercise program to meet your specific needs and show you how to exercise safely. Some treatment centres have professionals who are specially trained in exercise interventions for people with cancer.

More information

• To find a physiotherapist, visit the Australian Physiotherapy Association.
• To find an accredited exercise physiologist, visit Exercise & Sports Science Australia.

Download our booklet ‘Exercise for People Living with Cancer’ for examples of aerobic, strength-training and flexibility exercises

Balanced diet

Why it is useful – Cancer and its treatment both place extra demands on the body.

Research shows that eating well before, during and after treatment can help you cope better with treatment side effects and speed up recovery, increase energy and maintain wellbeing.

What to expect – Cancer Council recommends that most people with cancer follow the Australian Dietary Guidelines and:

• eat a balanced diet from the 5 food groups – fruit, vegetables and legumes, wholegrains, meat (or alternatives) and dairy (or alternatives)
• limit foods containing saturated fat, added salt and added sugars, avoid sugary drinks, and limit alcohol.

How to eat well – For some people, it is not always possible to eat well during cancer treatment. You may find it hard to eat enough or you may have trouble  eating some foods. This may mean that your food choices need to be different from the Australian Dietary Guidelines.

An accredited practising dietitian can:

• help ensure you meet your nutritional needs
• give you tailored advice on your food choices, nutrition and how to cope with any eating problems you may experience
• assist in managing side effects.

If you find swallowing food and drink difficult, a speech pathologist can help. 

More information

• To find an accredited practising dietitian, visit Dietitians Australia.
• To find a certified practising speech pathologist, visit Speech Pathology Australia.

Download our booklet ‘Nutrition for People Living with Cancer’

Other muscle and movement therapies

While studies into the use and safety of these therapies in people with cancer are limited, these forms of therapist-led movement exercise can help improve breathing, strength, flexibility, mobility, fitness and general wellbeing.

Bowen technique (Bowtech) – A therapist applies gentle pressure over acupuncture and reflex points to massage the muscles and soft tissue and tendons. A Bowen session lasts up to an hour and most people have 3–4 sessions.

Pilates – This system of strengthening and stretching exercises is designed to develop the body’s core (abdominals, lower back and hips). It encourages the mind to be aware of its control over the muscles and to change postural habits that have contributed to pain, reduced mobility and poor coordination. Pilates started as a form of physical therapy.

Alexander technique – Although not a type of exercise, this therapy teaches people ways to improve posture and movement, and to use muscles efficiently. By changing the way people use their body, this therapy can enhance mental and physical functioning.

Feldenkrais method – This series of guided movements focuses on balance and flexibility. It helps people become more aware of the way they move and how this contributes to, or compensates for, bad posture, pain and mobility restrictions. Trained therapists use touch, movement, guided imagery and mindful body awareness to stimulate the brain to improve movement and posture.

Should I change what I eat?

People often consider changing their diet to help their body cope with the effects of cancer and its treatments, and to give themselves the best chance of  recovery. Some complementary therapies incorporate general dietary advice, while others have their own specific approaches to diet.

While it’s best to get vitamins and minerals from eating whole foods, they are sometimes taken as supplements. For example, doctors may advise some people to take calcium or vitamin D supplements during and after treatment. If you were taking supplements before treatment, ask your cancer specialist if it is safe to continue.

Unproven diets

Some people claim that a particular diet or way of life can cure or control cancer on its own. Often these diets are promoted on social media or in the traditional media.

There are no special foods, diets or vitamin and mineral supplements that have been scientifically proven to cure cancer. There’s also no research that shows any particular foods can lower the chance of the cancer coming back.

Following an unproven diet may mean you don’t get enough energy (kilojoules/calories), protein, fat, carbohydrates, vitamins and minerals. This may affect your energy levels, cause unwanted weight loss and fatigue, and weaken your immune system.

Cutting out whole food groups and losing weight may also contribute to malnutrition. This may make it harder for you to cope with treatment and may slow down your recovery. You can become malnourished regardless of how much you weigh.

Taking care with special diets during treatment

During treatment, following the diets listed below may stop you getting enough nutrients for your body to work properly.

Gerson therapy – This involves drinking fresh juice several times a day, taking supplements, and having coffee enemas. There is no scientific evidence that Gerson therapy is an effective treatment for cancer, and evidence shows that coffee enemas can be dangerous if used excessively.

High doses of vitamins – Some people believe that taking high doses of certain vitamins strengthens the body’s immune system during cancer treatment. There is little evidence to support this claim. In fact, many vitamins and minerals can be toxic at high levels (for example vitamin E in high doses may increase the risk of bleeding). They may also affect how radiation therapy, chemotherapy and other drugs work.

Alkaline diet – This diet claims eating high alkaline foods such as green vegetables, fruits, oily fish and nuts lowers the acidity levels in the body. A low acid level is said to stop cancer growth, but there’s no evidence to support this claim.

Macrobiotic diet – Generally, this diet consists of wholegrains, fruits and vegetables, and soups made with legumes and fermented soy (miso). This diet may cause you to lose weight. There is no evidence this diet cures cancer.

Paleo diet – This diet consists of fruits, vegetables, seeds, nuts, meats and eggs, but excludes grains and dairy products. Eating grains is essential for a healthy digestive system. This diet is not recommended during cancer treatment.

Keep your complementary therapists and other health professionals informed about any special diets you try before, during or after cancer treatment. This will help them give you the best possible care.