Malnutrition is a serious condition that occurs when your diet doesn't contain the right amount of nutrients. Information on possible signs of malnutrition, how to prevent it and how it is treated is available below.

Causes of malnutrition

Malnutrition is a common health problem and occurs when you are not eating enough of the right foods or have a problem absorbing nutrients from food. This means you are not getting all the nutrients such as proteins, vitamins and minerals that you need.

Signs of malnutrition

The most common symptom of malnutrition is weight loss.

Being malnourished can make you ill, as your body needs the food as a fuel to make sure it functions properly. Being ill can also lead to malnutrition as this often leads to poor eating habits.

Other signs can include:

  • increased risk of illness and infection
  • slower wound healing
  • increased risk of falls
  • difficulty keeping warm
  • low mood
  • reduced energy levels
  • reduced muscle strength

All of these could result in you being admitted to hospital.

When to see your GP

You should visit your GP if you believe you or someone you care for is at risk of malnutrition. They can check for signs of malnourishment and any conditions that may cause malnutrition.

See your GP if your body mass index (BMI) is lower than 18.5 or you notice the above symptoms. 

BMI is a measure of whether you're a healthy weight for your height. You can use the healthy weight calculator below to work out your BMI.

You can also use the tool below to check your risk level of malnutrition. It has been developed by BAPEN, a charitable association that raises awareness of malnutrition in the UK.

It should not be used as a substitute for seeing a medical professional if you have any concerns about malnutrition.

More information about BAPEN is available on their website.

Treating malnutrition

Depending on what's caused you to become malnourished and how severe it is, treatment may be carried out in your home, in your care home or in some cases, hospital.

Changes to your diet are the main treatment for malnutrition. If you're undernourished, you may need to increase the nutritional content of your food, with or without taking nutritional supplements.

If you're unable to eat enough to meet your nutritional needs you may need a:

  • feeding tube to provide nutrients directly into your digestive system
  • drip to provide nutrients and fluids directly into a vein

For more information on treatment for malnutrition, go to the page below:

Preventing malnutrition

The best way to prevent malnutrition is to eat a healthy, balanced diet. Try not to miss or skip meals and aim to eat three small meals a day and two to three snacks a day if your appetite is poor. Take drinks after your meal, not before or during as that can fill you up.

A healthy, balanced diet is vital for maintaining health and fitness. To stay healthy, you need to eat a variety of foods from the four main food groups including:

  • fruit and vegetables
  • starchy foods, such as rice, pasta, bread and potatoes
  • milk and dairy foods
  • meat, fish, eggs and beans and other non dairy sources of protein

The Eatwell Guide shows the different types of food you need to eat (and in what proportions) to maintain a well-balanced and healthy diet.

If your malnutrition (or your risk of malnutrition) is caused by an underlying health condition, you may have more complex dietary needs or you may need additional items in your diet such as nutritional supplements. Your GP or the doctor in charge of your care will be able to advise you and refer you to a registered dietitian.

To find out more about healthy eating go to:

If you are losing weight and want to increase your nutritional intake, go to:

The information on this page was provided by the Health and Social Care Board.

For further information see terms and conditions.

This page was reviewed April 2018

This page is due for review June 2020

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