Diet and secondary breast cancer

If you have secondary breast cancer, you might wonder whether you should make any changes to your diet.

There’s no scientific evidence that you need to follow a special diet if you have secondary breast cancer, or that a particular diet can make a difference to your outlook (prognosis).

However, a healthy, balanced diet can have many health and wellbeing benefits.

Should I avoid certain foods?

You don’t need to cut out any specific foods if you have secondary breast cancer.

But it’s a good idea to follow NHS healthy eating guidelines and try to eat foods high in sugar, salt and saturated fat less often if you can.

If you’re unable to eat a healthy balanced diet or are struggling to get essential nutrients or vitamins from your diet, you may be prescribed a dietary supplement. However, unless you’re having problems, you do not need to take supplements.

Some people wonder whether certain supplements, such as vitamins, herbal remedies or probiotics, might help ease their symptoms or treatment side effects. But there’s conflicting evidence about the safety and effectiveness of many products.

Supplements do not have to comply with the same regulations or go through the same rigorous testing as conventional medicines.

They may also affect how certain cancer treatments work, such as chemotherapy and radiotherapy.

How can I check if a supplement will affect my treatment?

You can check if a supplement might interact with your treatment on these websites:

• Complementary and Alternative Medicine for Cancer (CAM Cancer)
• Memorial Sloan Kettering Cancer Center

Talk to your breast care nurse, treatment team, pharmacist or GP before taking any supplements or other treatments bought over the counter or online.

Having radiotherapy normally doesn’t cause any dietary problems but it’s still good to eat a balanced diet and drink plenty of fluids.

If you’re having radiotherapy around your collarbone or breastbone, you may have a sore throat, dry mouth or difficulty swallowing. If this happens, speak to your treatment team. Taking liquid pain relief, such as liquid paracetamol, before eating may help.

If you have to travel for your treatment, take a drink and snack with you and plan meals that are easy to prepare for when you get home.

Read more about shopping and cooking during treatment.

Changes to how your food tastes are very common, particularly if you’re having treatment such as chemotherapy or some targeted therapies.

You may find that food tastes bland or just different. You might prefer to eat strongly flavoured foods, or use herbs and spices when cooking. Try a variety of foods to find the ones you like the best. As well as going off your usual foods, you may like foods you previously didn’t like.

You might find these tips for managing taste changes helpful:

• Drink plenty of fluids like water and herbal teas throughout the day (aim for 6 to 8 glasses a day)
• Try rinsing your mouth with water before and after eating
• Try sugar-free gum to help your body produce saliva
• Try flavoured teas, juices, lemonade or ginger ale as they can help mask unpleasant tastes. Sucking fruity sweets or mints may help too
• Try experimenting with different textures, flavours and temperatures of food to find what works for you
• If you have a metallic taste in your mouth when you eat, use plastic cutlery and non-metallic utensils and pans
• Try adding strong flavours like strong cheese, bitter jams, stock cubes or pots, or Marmite to your food for extra flavour

See more tips and information about taste changes.

You might find you can’t eat as much as usual. This can make it hard to maintain your weight and get enough energy.

If you have less appetite than normal, it could be due to the effects of the cancer, your treatment or anxiety. You might not feel hungry or feel full after only eating a small amount. You may also feel sick or be sick after eating.

If you have problems eating, the following tips may help:

• Eat smaller amounts more often rather than trying to eat a large plate of food at set mealtimes
• Add high-energy ingredients and foods containing protein to your meals – for example, add cream or butter to mashed potatoes and vegetables, grated cheese to soups, and syrup or jam to porridge or desserts
• Avoid strong-smelling foods that may put you off your meal
• Snack on high-calorie foods and drinks such as chocolate, cake, crisps, nuts or milkshakes to give you energy
• Do something active, if you feel able to, as exercise can help increase your appetite – you might have more of an appetite if you take a short walk before eating
• Take your time eating, and if you have a dry mouth have a glass of water at hand

If you’re still struggling to eat enough or you’re losing weight, talk to your treatment team or nurse about nutritional supplements or ask to speak to a dietitian for specialist advice.

For more information, Macmillan Cancer support has a booklet called The building-up diet. You can order it free from their website.

You might gain weight, especially if your appetite increases or taste changes are affecting your diet. You may also put on weight as a result of treatment – for example, if you’re taking steroids or are unable to do as much exercise.

If you’re worried about gaining weight, the following tips may help:

• Choose low-fat foods and drinks
• Eat plenty of fresh fruit and vegetables
• Check labels for the sugar content of food (some “diet” foods contain lots of sugar)
• Avoid sugary drinks

If weight gain becomes a problem for you, it might help to talk to your GP or a dietitian, who can advise you about diet and help to monitor your weight.

If you want to exercise, speak to your treatment team to find out if there are any limitations on the type or intensity of exercise you can do. Your GP can refer you to an exercise programme in your local area. These can be helpful to people with secondary breast cancer, including those wanting to lose weight.

It’s not uncommon to feel sick or be sick while living with secondary breast cancer, but there are a number of things that can help.

In most cases, feeling sick and being sick can be controlled using anti-sickness medication. It’s important for your treatment team to find the cause so it can be managed effectively. You can help your treatment or palliative care team decide what treatment will work best by keeping a record of what makes it worse or when it happens.

Some pain relief can make you feel sick when you first take it, but this usually wears off. You may be prescribed an anti-sickness tablet to take with your pain relief to stop this happening.

You might also find the following tips helpful:

• Drink plenty of fluids like water or herbals teas – ginger and mint tea can help settle the stomach
• Try to take small sips as you drink
• Eat little and often
• Try to eat cold foods if you find the smell of hot foods makes you feel sick

Constipation can be caused by eating or drinking less than usual, not eating enough fibre and lack of exercise. Some drugs can cause constipation, including chemotherapy and some pain relief.

Consuming high-fibre foods can help if you’re constipated. These include:

• High-fibre breakfast cereal, such as bran flakes or shredded wheat
• Beans and lentils
• Vegetables (fresh or frozen)
• Fruit (fresh, frozen, canned and dried)
• Brown rice
• Wholemeal bread
• Wholewheat pasta

You should also drink plenty of fluids (6 to 8 glasses of water a day) and do some regular, gentle exercise such as walking. If you’re still having problems with constipation, ask your treatment team or GP for advice.

Laxatives can help relieve constipation, especially if you’re on regular pain relief. Your GP, treatment team or palliative and supportive care team can prescribe these for you.

Treatments such as chemotherapy and radiotherapy to the spine or pelvis may cause diarrhoea. Other drugs can also affect the digestive system and cause diarrhoea.

If you have regular diarrhoea, your body can’t absorb water and nutrients from food or any medications taken by mouth.

If the medication you’re having is known to cause diarrhoea, your treatment team may prescribe drugs to help control it.

Try to drink plenty of fluids during the day, reduce foods high in fibre, eat little and often and minimise fatty foods.

You may be given specific advice, but generally if you have more than 4 episodes of diarrhoea in 24 hours, tell your treatment team or palliative and supportive care team.

For further support, you can talk to your treatment team or breast care nurse, or ask to speak to a dietitian for specialist advice. You can also speak to our specialist nurses on our free helpline – see below.

You can find more useful information about diet and breast cancer on the World Cancer Research Fund website. You can also find a series of helpful videos about diet and cancer on the Royal Surrey NHS Foundation Trust’s website.

Our Living with Secondary Breast Cancer services also have a range of support options – see below.