Oral Nutritional Supplements (ONS) in Cancer Care

During cancer and treatment, your body's nutritional needs can significantly increase. Supplying your body with adequate nutrients is important to help maintain your weight and muscle mass. Changes in your nutritional status can also affect your treatment plan. 

However, side effects of cancer and its treatment often make it hard to get enough of the calories, protein and other nutrients you need in increased amounts. Oral nutritional supplements may be recommended by your doctor to help fill nutrition gaps when a normal diet alone isn’t enough.

Oral nutritional supplements (also called ONS), are food products specifically designed to help patients who, due to their disease or medical condition, have different nutritional needs that cannot be met by their normal diet alone. ONS can provide additional calories, protein, and other key nutrients your body needs during cancer. 

Your dietitian or other healthcare provider may recommend an oral nutritional supplement as part of your nutrition care plan if you're finding it difficult to meet your nutritional needs through food alone. They don’t require cooking or time-consuming preparation and are available in different formats such as ready-to-drink shakes, mixable powders, juices, puddings, and yoghurt-style foods. 

These oral nutritional supplements are also designed to be used along with your regular diet, not replace it — so you can still eat and drink your favourite foods when you’re feeling up to it. 

Oral nutritional supplements for patients with cancer provide extra protein, calories and other important nutrients to meet their increased nutritional needs during cancer treatment. 

Cancer changes your metabolism, causing you to burn more calories than usual and lose weight and muscle more quickly than usual. At the same time, cancer treatments often cause side effects like nausea, vomiting, mouth sores, and fatigue, making it hard to eat. As a result, people with cancer are at a high risk of malnutrition, which can worsen side effects like fatigue and increase infection risk (1). 

These supplement drinks provide significant calories and protein, along with vitamins, minerals and other nutrients in a small serving. By helping to fill the nutritional gap, ONS can help minimise weight loss and support maintenance of muscle mass. 

Oral nutrition supplements are not meal replacements, nor are they protein shakes. Instead, they help patients who cannot meet their increased nutritional needs during cancer, even with a modification of their normal diet.

When advised by your doctor or dietitian, you can use an oral nutrition supplement any time of day. Since they can be filling, many people prefer to eat or drink them in between meals or as a bedtime snack. It’s OK to sip on your nutrition supplement throughout the day, but once opened, follow the storage instructions on the label. 

Many people find it hard to eat enough to meet their body’s nutritional needs during cancer. If you’re struggling, tell your healthcare provider. They can evaluate your situation and, when needed, recommend medical nutrition to help you meet your body's specific nutritional needs during the disease. 

†Oral nutritional supplements are foods for special medical purposes and must be used under medical supervision. Check with your doctor if you would like to understand if oral nutrition supplements may be suitable for you.