The main symptom of malnutrition (undernutrition) is unintended weight loss, although this isn't always obvious.
Most people who are malnourished will lose weight, but it is possible to be a healthy weight or even overweight and still be malnourished.
Someone could be malnourished if:
- they unintentionally lose 5-10% of their body weight within three to six months
- their body mass index (BMI) is under 18.5 (although a person with a BMI under 20 could also be at risk) – use the BMI calculator to work out your BMI
- clothes, belts and jewellery seem to become looser over time
See your GP if you've unintentionally lost a lot of weight over the last few months.
If you notice a friend or family member has lost lots of weight, talk to them about your concerns and encourage them to get help.
Other signs of malnutrition include:
- reduced appetite
- lack of interest in food and drinks
- feeling tired all the time
- feeling weaker
- getting ill often and taking a long time to recover
- wounds taking a long time to heal
- poor concentration
- feeling cold most of the time
- low mood or depression
See your GP if you have these symptoms. If you notice these problems in someone else, try to encourage them to get help.
Symptoms in children
Symptoms of malnutrition in a child can include:
- not growing at the expected rate or not putting on weight as would normally be expected (faltering growth)
- changes in behaviour, such as being unusually irritable, slow or anxious
- low energy levels and tiring more easily than other children
Contact your GP if you're concerned about your child's health or development at any point.
Page last reviewed: 17 February 2017
Next review due: 17 February 2020