Meal replacement

What is meal replacement?

Meal replacement refers to a food or drink that’s intended to replace a solid meal. It often comes as a shake, but it can also include things like soups, snack bars or other drinks.

You can use meal replacements as either a means to help you lose weight (like slimming shakes) or to help you to gain weight or take in more nutrition if you’re malnourished, or at risk of becoming malnourished.

Meal replacements are regulated to provide a reasonable amount of your essential nutrients and calories for the day, so that you can safely use them to replace some of your meals without the risk of you not meeting your nutritional needs. But because a serving often contains less calories than a meal, it’s recommended that you don’t use them consistently for more than three weeks unless your clinician has told you otherwise.

How do weight loss shakes work?

Weight loss shakes work by regulating your calorie intake, so that if you follow the ‘plan’ that’s been set out, you’ll take in less calories than you burn. When you burn more calories than you take in from food and drink, you’re running on a ‘calorie deficit’, which means that your body has to burn its fat stores for energy, meaning that you’ll lose weight as a result.

Basically, weight loss shakes do the heavy lifting for you - meaning that you don’t need to think about what you’re going to eat, count calories or spend a lot of time cooking healthy or low-calorie meals.

How do nutritional supplement drinks work?

Nutritional supplement drinks are essentially designed to do the opposite of weight loss shakes. They’re usually fairly dense in calories, and are often intended to supplement, rather than replace, a food-based diet.

It might be recommended to you if you’re malnourished, or are at risk of becoming malnourished, to drink nutritional supplement drinks throughout the day or between meals in order to increase your weight and improve your health. This can often be useful if you’re elderly, as malnutrition is particularly common and dangerous in older populations (especially if you suffer with low mood, cognitive impairment or other health conditions).

Because they’re rich in calories and nutrients, they make it easier for you to take in more calories than you use - and so create a calorie surplus. This means that you can build muscle and fat stores and support your body’s healthy function. When people are malnourished, it means that their bodies aren’t working as effectively as they could be. As such, getting to a healthy weight is important to help your body to fight off illnesses, keep your brain working at its best and to maintain your energy levels.

Medically reviewed by

Dr Daniel Atkinson

GP Clinical Lead

on February 10, 2023.

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