Supplement Drinks for Older Adults: Simple, Essential Guide

Nutritionally complete supplement drinks, often called oral nutritional supplements, are concentrated drinks or powders that provide energy, protein, vitamins and minerals for people who cannot eat enough, such as older adults with a small appetite or people recovering from illness. Clinical guidelines recommend them for older people who are malnourished or at risk when food-based changes are not enough, and reviews show they increase energy and protein intake and body weight. They are not diet shakes or sports protein drinks, and they work best between meals as part of a plan with a doctor or dietitian.

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This guide explains what “nutritionally complete” means, who these drinks are designed for, how to spot unplanned weight loss, what the research shows, how to compare labels, how to get them down when appetite is poor, and when to get professional advice.

At a glance

• Designed for people who cannot eat enough, not for weight loss or gym goals.
• Guideline target: European clinical guidelines (ESPEN) suggest that when supplement drinks are used for older adults, they provide at least 400 kcal and 30 g of protein a day.
• Compare per prepared serve: energy and protein per serve as made up, not per scoop or per 100 g of powder.
• Between meals, not instead of them: so they add to food rather than replace it.
• Talk to your doctor, pharmacist or dietitian about unplanned weight loss, diabetes, kidney disease, swallowing problems or if you take other supplements.

What “nutritionally complete” means

An oral nutritional supplement provides energy, protein, vitamins and minerals in a concentrated form. “Nutritionally complete” means that, at a stated amount per day, the product supplies all the essential nutrients a person needs, so it could in principle be the only source of nutrition. In practice, most people use these products alongside food to top up what they can manage to eat.

How they are regulated depends on the country. In Australia and New Zealand, many are sold as foods, and those intended for medical use fall under the Food Standards Code standard for food for special medical purposes. In the European Union they are covered by rules for food for special medical purposes, and in the United States some are sold as medical foods. Whatever the category, the same brand often makes several versions, so the label matters.

How they differ from other shakes

Product type	Designed for	Typical profile	Use with care
Oral nutritional supplement (standard)	People eating too little	Balanced energy, protein, vitamins and minerals	Often contains sugar; check with diabetes
High-energy or compact versions	People who fill up quickly	More energy and protein in a smaller volume	Sip slowly; can cause fullness
Diabetes-specific formulas	People with diabetes who need nutrition support	Modified carbohydrate for less effect on blood glucose	Still needs advice on amount and timing
Meal-replacement diet shakes	Weight loss	Lower energy per serve	Unsuitable for someone losing weight unintentionally
Sports protein shakes	Active adults adding protein	Mainly protein, few added micronutrients	Not interchangeable with nutrition support drinks; see our protein powder comparison

Who they are designed for

• Older adults with a small appetite or unplanned weight loss.
• People recovering from surgery, illness or a hospital stay.
• People with conditions that make eating difficult, such as some cancers, swallowing problems or chronic lung or heart disease.
• Anyone identified by a health professional as malnourished or at risk of malnutrition.

For healthy adults who eat well, they add little beyond kilojoules.

Why malnutrition is easy to miss

Undernutrition is common among older adults everywhere, particularly in hospital, residential care and among people living alone. It can be hard to see: a person can be overweight and still be losing muscle and missing nutrients. Health services use simple screening tools, such as the Malnutrition Universal Screening Tool (MUST) and the Mini Nutritional Assessment (MNA), which combine weight, recent weight loss, appetite and illness to flag people who need help.

Signs worth raising with a doctor or dietitian:

• Clothes, belts, rings or dentures becoming loose.
• Meals regularly left half eaten, or meals skipped.
• Less interest in food, or difficulty chewing or swallowing.
• Weaker grip, slower walking or more falls.
• Unplanned weight loss over the past three to six months.

What the research shows

The European Society for Clinical Nutrition and Metabolism (ESPEN) guideline on clinical nutrition in geriatrics (2019) recommends offering oral nutritional supplements to older people who are malnourished or at risk when dietary advice and food fortification are not enough. It recommends that, when used, they provide at least 400 kcal (about 1,700 kJ) and 30 g of protein a day, and that they continue for at least a month with regular review.

A Cochrane review of protein and energy supplementation in older people (Milne and colleagues, 2009) found small but consistent weight gain, and some evidence of fewer complications and deaths in people who were already undernourished, mainly in hospital settings. Effects on longer-term function and quality of life are less consistent, partly because people often do not drink the full amount suggested. The products only help if they are actually consumed, so flavour, volume and timing are practical issues, not trivial ones.

How to read the label

Energy and protein per prepared serve

Compare kilojoules (or kilocalories) and grams of protein per prepared serve, not per scoop or per 100 grams of powder. One kilocalorie is about 4.2 kilojoules. Compact high-energy versions deliver more in a smaller volume, which suits people who feel full quickly. Protein matters particularly for older adults trying to keep muscle; see our article on protein and muscle after forty.

How it is meant to be made up

Powders are designed to be mixed with a set amount of milk or water. Mixing with milk adds protein and energy; mixing with water reduces both, and the label’s nutrition figures usually assume one or the other. Using less liquid than stated does not make the product usefully stronger and can be harder to digest.

Sugar, lactose and fibre

Many standard formulas contain a fair amount of sugar for energy and flavour. People with diabetes should ask a dietitian about suitable versions. Some formulas are low in lactose or add fibre, which can matter for people with bowel symptoms.

Vitamins and minerals: watch the totals

Because these drinks contain a full range of micronutrients, adding a multivitamin on top may be unnecessary. Two or three serves a day can supply a large share of daily vitamin A, vitamin D, iron and other nutrients. If you also take other supplements, check the combined amounts against upper limits with a pharmacist. Our guides to multivitamins after 50 and reading a vitamin D label explain the units, and our step-by-step guide to reading a supplement label covers the rest of the panel.

Texture

For people with swallowing difficulties, drinks may need to be thickened to a specific level. Many countries use the International Dysphagia Diet Standardisation Initiative (IDDSI) levels; a speech pathologist or dietitian should set the level rather than guessing.

Label comparison checklist

1. Energy per prepared serve, in kJ or kcal.
2. Protein per prepared serve, in grams.
3. Serve size and how many serves a day the label suggests.
4. What to mix it with (milk or water), and whether the nutrition panel assumes it.
5. Sugar per serve, and whether a diabetes-specific version exists.
6. Lactose, fibre and allergens such as milk, soy or gluten.
7. Vitamin and mineral amounts per day at the suggested number of serves, compared with any other supplements taken.
8. Whether it is labelled as a food for special medical purposes, which usually means it should be used under medical supervision.

Practical tips for getting them in

• Serve them between meals, such as mid-morning, mid-afternoon or before bed, so they add to food rather than replace it.
• Try them chilled, or blended into smoothies, soups, custards or desserts if the flavour is a barrier. Check the label before heating, as some products should not be boiled.
• Split a serve into smaller sips through the day.
• Rotate flavours to avoid taste fatigue.
• Keep offering real food: small, frequent, energy-dense meals and snacks remain the foundation.
• Pair nutrition with gentle strength work where possible, as muscle responds to both; see our guide to resistance bands for beginners.

Common mistakes

• Using a diet shake for someone who is losing weight unintentionally.
• Serving the drink with meals, so the person eats less food and gains nothing overall.
• Comparing per 100 g of powder instead of per prepared serve.
• Doubling up on vitamins and minerals with a multivitamin or separate supplements.
• Buying in bulk before checking taste and tolerance with a single tin or small pack.
• Treating the drink as the fix without asking why the weight loss is happening.

When to get professional advice

These drinks are safe for most people, but they work best as part of a plan. A doctor or accredited dietitian can work out why someone is losing weight, how much nutrition they need, and which product suits them, especially for people with diabetes, kidney or liver disease, swallowing difficulties or tube feeding, where specialised products and textures may be needed. Unplanned weight loss in an older adult always deserves a medical check.

If you are deciding between a supplement drink and other products, our plain-English guide to choosing supplements sets out when food comes first and when a supplement makes sense.

Sources this guide draws on: Volkert D and colleagues, ESPEN guideline on clinical nutrition and hydration in geriatrics, Clinical Nutrition (2019); Milne AC and colleagues, protein and energy supplementation in elderly people at risk from malnutrition, Cochrane Database of Systematic Reviews (2009); British Association for Parenteral and Enteral Nutrition, the Malnutrition Universal Screening Tool; Guigoz Y, the Mini Nutritional Assessment review of the literature, Journal of Nutrition, Health and Aging (2006); Food Standards Australia New Zealand, Food Standards Code standard for food for special medical purposes; International Dysphagia Diet Standardisation Initiative framework; NHMRC Nutrient Reference Values.

Frequently asked questions

What is the difference between a supplement drink and a protein shake?

Sports protein shakes mainly provide protein, usually with modest energy and few added vitamins and minerals. Oral nutritional supplements provide a balanced mix of energy, protein, vitamins and minerals for people who cannot eat enough. They are not interchangeable.

Can supplement drinks replace meals?

Some can be used as the only source of nutrition under medical supervision, for example for people who cannot eat solid food. For most people the aim is to use them alongside meals, because food provides fibre, variety and the pleasure of eating.

How many serves a day are needed?

It depends on how much the person is eating and their needs. One to three serves a day in addition to food is common, and ESPEN suggests at least 400 kcal and 30 g of protein a day when they are used for older adults. A dietitian can set a target based on weight, appetite and health.

Are they safe for people with diabetes?

Standard formulas contain sugar and can raise blood glucose. Diabetes-specific formulas are designed to have less effect. People with diabetes should ask their doctor or a dietitian which product and how much.

Can they cause side effects?

Some people notice fullness, bloating or diarrhoea, particularly if they drink a serve quickly or have trouble with lactose. Sipping slowly, chilling the drink or trying a different formula can help. Anyone with kidney or liver disease should get tailored advice.

Should I use one if I want to build muscle?

For healthy, active adults, everyday food plus, if needed, a protein shake is usually more appropriate. Oral nutritional supplements are designed for people at risk of malnutrition rather than training goals.

Nutritionally complete supplement drinks are a practical tool for people who cannot eat enough, especially older adults and people recovering from illness. Choose by energy and protein per prepared serve, mix as directed, serve between meals, watch vitamin and mineral totals, and involve a health professional whenever weight loss or poor appetite is the reason you are buying them.

This article is general education only. It is not medical advice and does not replace advice from your own doctor, pharmacist or accredited dietitian, particularly if you are pregnant, take medicines or have a health condition. Products are discussed by category, not endorsed; the only affiliate links are to the practical items listed near the end.