In the world of nutrition, there’s no one-size-fits-all approach. While a balanced diet is the cornerstone of good health, some individuals may struggle to meet their nutritional needs through food alone. This is where oral nutritional supplements (ONS) come into play. These specially formulated products can be a lifeline for those at risk of malnutrition or with increased nutritional requirements. But what exactly are they, who are they for, and how do dietitians’ decide when they’re needed? Let’s break it down.
What are Oral Nutritional Supplements?
Oral nutritional supplements (ONS) are designed to provide extra calories, protein, vitamins, and minerals to individuals who may not be getting enough from their regular diet. They come in various forms, including ready-to-drink shakes, powders, soups, and even pudding-like desserts. While they’re not a replacement for food, they can be a valuable tool to bridge nutritional gaps.
Types of ONS
There’s a wide range of ONS available, each tailored to meet specific needs. Here are some of the most common types:
- High-calorie supplements
These are designed for individuals who need to gain weight or maintain their current weight, such as those recovering from surgery, living with a chronic illness, or experiencing unintentional weight loss. - Protein-focused supplements
Protein is essential for tissue repair, immune function, and muscle strength. Protein-rich ONS are often recommended for older adults, athletes, or those recovering from illness or injury. Many high protein ONS are also high in calories and are fortified with vitamins and minerals, and so may be considered nutritionally complete. - Disease-specific supplements
Certain medical conditions, such as diabetes, kidney disease, or cancer, may require specialised nutritional support. For example, formulas for those with kidney disease will have different amounts of protein within them, and less minerals such as phosphate or potassium to reduce the risk of complications. Equally, ones more suitable for those with diabetes may have less simple sugars in them. - Fibre-enriched supplements
For individuals with digestive issues or those at risk of constipation, fibre-enriched ONS can help promote gut health and regularity. These don’t tend to be the standard prescribed; often, they will be prescribed if symptoms occur or if initially clinically indicated. - Vitamin and mineral fortified supplements
Most supplements will contain vitamins and minerals, in varying quantities; not all are nutritionally complete, so ask your dietitian to see if the one you are prescribed is.
Who might need ONS?
While ONS can be beneficial, they’re not necessary for everyone. We dietitians carefully assess individuals to determine whether supplements are appropriate. Here are some common scenarios where ONS might be recommended:
- Malnutrition or risk of malnutrition
Malnutrition can occur for various reasons. Dietitians use tools like the Malnutrition Universal Screening Tool (MUST) to identify need and prescribe appropriately. - Chronic illnesses
Conditions like cancer, COPD, or inflammatory bowel disease can increase nutritional requirements or make it difficult to eat enough. Equally, some conditions can impact the absorption of certain nutrients. ONS can help ensure these individuals get the nutrients they need to support their health and recovery. - Pre/post-surgery or recovery
Before or after surgery, or during recovery from an illness, the body’s nutritional needs are often higher. ONS can provide the extra energy and protein required to aid healing and rebuild strength. - Dysphagia
Dysphagia, or difficulty swallowing, can mean that people may require different textures of food. Because of this, eating enough can be difficult to manage nutritional needs. Pre-thickened or correct texture ONS can be a good way of maintaining nutritional intake. - Limited food intake
Individuals with limited food choices due to allergies, intolerances, or sensory issues may benefit from ONS to ensure they’re meeting their nutritional needs.
How do we as dietitians decide who needs ONS?
Dietitians take a holistic approach when assessing whether someone might benefit from ONS. We will generally use the MUST tool to identify if someone is at risk. We will also consider:
- Dietary Intake: Is the person eating enough to meet their nutritional needs? Where are they getting their calories from? Are they able to drink more than they are able to eat? Are there specific food groups they cannot have, making them at a higher risk for malnutrition of certain nutrients?
- Weight Changes: Have they experienced unintentional weight loss or gain within the past 3-6 months? We would generally look for a weight loss of over 5% in the past 3-6 months that was unintentional to diagnose someone as being at risk of malnutrition.
- Medical History: Do they have a condition that increases their nutritional requirements, such as cystic fibrosis or a cancer? Does their medical condition impact absorption of nutrients, such as uncontrolled coeliac disease or IBD? If ONS is indicated, do they have any medical conditions which mean certain ONS would not be appropriate, such as kidney disease?
- Lifestyle Factors: Are there barriers to eating, such as difficulty cooking or shopping? Do they have the ability to cook or store food at home? Is there anyone that can help them prepare food?
- Biochemical Markers: Do they have any overt deficiencies?
Based on this assessment, dietitians may recommend ONS as part of a broader nutrition plan. We will also monitor progress and adjust recommendations as needed.
A word of caution
While ONS can be incredibly helpful, they’re not a substitute for a balanced diet. Over-reliance on supplements without addressing underlying dietary issues can lead to other health problems. It’s always best to work with a dietitian or healthcare professional to ensure ONS are used appropriately.
Final Thoughts
Oral nutritional supplements are a valuable tool in the dietitian’s toolkit, offering a practical way to support those who struggle to meet their nutritional needs through food alone. Whether it’s aiding recovery, managing a chronic condition, or simply ensuring older adults stay well-nourished, ONS can make a real difference. However, they’re not a one-size-fits-all solution, and their use should always be guided by a qualified professional.
If you or someone you know is struggling to meet their nutritional needs, don’t hesitate to reach out to a dietitian such as myself. They can help determine whether ONS might be beneficial and create a plan that supports overall health and wellbeing. After all, good nutrition is the foundation of a healthy life—and sometimes, a little extra support can go a long way.
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