This leaflet provides information on dietary and herbal supplements, and will help you make an informed decision regarding whether they are appropriate to take during your cancer treatment.
What are dietary supplements and herbal remedies?
Dietary supplements or herbal remedies contain one or more nutrients including vitamins, minerals, herbs and plant extracts and can come in the form of tablets, capsules, powders or drinks.
Even though they can be bought from health shops or pharmacies and are often taken with the aim to improve health and wellbeing, they may not be safe to use while having treatment for your cancer.
Should I take dietary supplements during my cancer treatment?
Vitamins and minerals are important to help our bodies work properly. You should try to meet your nutritional needs by having a varied, healthy, balanced diet containing fruits, vegetables, whole grains, and protein. If you eat a healthy and varied diet, it’s likely you will already be getting all the vitamins and minerals your body needs. Supplements should NOT be used as an alternative to a balanced, varied diet.
If you are unable to eat a diet with enough nutrients and want to take a supplement, then a standard multivitamin and mineral supplement that contains up to 100% of the Recommended Daily Allowance (RDA) can be taken.
Make sure you do not exceed the stated dose and avoid taking more than one product containing the same vitamin or mineral. Also check that the product does not contain any other ingredients such as herbs or plant extracts, as this would make it unsuitable.
Although there has been a lot of research into the use of dietary supplements and cancer there is not enough evidence to prove that they can help treat cancer or stop it coming back. The World Cancer Research Fund UK has reviewed various studies and advise against taking supplements to reduce your cancer risk.
Should I take probiotics during my cancer treatment?
Probiotics contain live bacteria and yeasts and are often added to yoghurts or taken as food supplements.
Whilst undergoing treatment, there is a small risk that probiotics could cause an infection which your body will not be able to fight as well as normal. This is because some cancer treatments can lower the number of white blood cells in the body which fight infection.
We recommend
That probiotic products are NOT taken whilst receiving cancer treatment, or if your immune system is weakened from treatment.
Problems with supplements or herbal remedies
- They may interfere with your cancer treatment – potentially stopping it working as well as it should.
- They may cause unwanted side effects.
- They may affect hormone-sensitive conditions e.g. breast cancer even after treatment has been completed.
What does this mean for my treatment?
We are asked frequently by patients whether they are able to take herbal remedies or dietary supplements alongside cancer treatment. For many years we have been looking into each request on an individual basis, and the great majority of the time we find that there is insufficient evidence to make a good recommendation about the safety or otherwise of these products.
We have therefore decided to ask that patients do not take herbal remedies or dietary supplements alongside chemotherapy/immunotherapy. Some exceptions to this are mentioned in the leaflet summary.
Summary
We recommend that you do not take supplements/herbal remedies during treatment for cancer unless you are advised to do so by your doctor.
Exceptions to this are:
- Vitamins or minerals prescribed to treat a known deficiency or as a supportive medication for some cancer treatments.
- A multivitamin/multimineral (containing up to 100% RDA) if you are unable to eat a normal, balanced diet.
- High calorie nutritional supplements as recommended by a dietician.
Contact your team
After reading this leaflet, if there is a supplement or herbal remedy that you feel strongly about taking, then please do discuss this with your Consultant, Nurse Specialist or Pharmacist.
Please note that it normally takes some considerable work by the pharmacy team to investigate possible interactions of supplements with cancer treatment.
This is therefore not the sort of query that the nursing staff will be able to provide an immediate answer to in pre-assessment or on the day units.
Further support
Please see the details below for more information about supplements.