Nutritional supplements

If you are not managing to eat enough, or are losing weight, your dietitian, GP, cancer doctor or specialist nurse may recommend nutritional supplements.

About food supplements

Your dietitian, GP, cancer doctor or specialist nurse may recommend nutritional supplements if you are not managing to eat enough, or are losing weight.

The types of nutritional supplements available include:

  • milk-based supplements
  • juice-tasting supplements
  • soups
  • powders that are made into drinks with water or milk
  • ready-made puddings
  • concentrated liquids.

They come in many different flavours. You can sometimes get these products from your chemist or supermarket. But sometimes your doctor, nurse or dietitian needs to prescribe them for you. You should only use high-protein or high-energy supplements as your doctor or dietitian tells you.

If you are vegetarian or vegan, or if you have a dietary intolerance, such as to dairy (lactose) or gluten, ask your GP, specialist nurse or dietitian to prescribe suitable food supplements.

If you are diabetic, it is important to get advice from your GP, specialist nurse or dietitian before using nutritional supplements.

Powdered drinks

Some powdered drink supplements can be used to replace a meal. You can mix them with fortified milk, regular milk or water. Sometimes your doctor will prescribe these supplements. Or you can buy them from a chemist or supermarket.

You can mix some powder supplements into food. You can add them to soup, custards or milk puddings. Sometimes companies that make the powders have recipes on their websites.

Milk-based supplements

Milk-based supplements are available on prescription in a range of flavours including sweet, savoury and neutral flavours. They usually need to be used within 24 hours. If you can only manage small amounts at a time, you can pour some into a glass and keep the rest in the fridge.

Juice-tasting supplements

These ready-made, flavoured supplements are available on prescription.

If you find them too sweet, you can dilute them with water or fizzy drinks such as soda or tonic water. You can also put them into jellies or puddings.

High-energy and juice-tasting supplements have a high sugar content. If you are diabetic, talk to your dietitian before using them. These drinks may not be suitable if you have a sore mouth or throat, as they may sting.

If you have had radiotherapy for certain types of head and neck cancer, you may be more at risk of tooth decay. It is best to avoid having sugar too often.

It is a good idea to clean your teeth or use a mouthwash after any sugary snacks. Make sure you have your teeth regularly checked by a dentist. Your GP, nurse or dietitian can give you more advice about this.

Fat-based liquids

You can take fat-based liquids separately in small doses. Or you can add them to some foods. Your doctor or dietitian will give you advice on how and when you should use this type of supplement.

Energy and protein powders and gels

Unflavoured powders and gels are available on prescription from your GP or dietitian. These are almost tasteless. You can add them to drinks, soups, sauces and gravies, casseroles, milk puddings and desserts.

Your dietitian can explain how much powder to use in different meals or drinks.

Related pages

About our information

  • References

    Below is a sample of the sources used in our building-up diet information. If you would like more information about the sources we use, please contact us at

    European Society for Clinical Nutrition and Metabolism (ESPEN). ESPEN guidelines on nutrition in cancer patients. February 2017 [accessed Jan 2020] 

    European Society for Clinical Nutrition and Metabolism (ESPEN). ESPEN expert group recommendations for action against cancer related malnutrition. June 2017 [accessed Jan 2020] 

    World Cancer Research Fund (WCRF). Healthy living after cancer. 2016. [accessed Jan 2020]      

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Chief Medical Editor, Professor Tim Iveson, Consultant Medical Oncologist.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

Date reviewed

Reviewed: 01 August 2020
Next review: 01 August 2023

This content is currently being reviewed. New information will be coming soon.

Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

Our cancer information meets the PIF TICK quality mark.

This means it is easy to use, up-to-date and based on the latest evidence. Learn more about how we produce our information.