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Being underweight

Weighing too little is not good for your health and can contribute to a weakened immune system, fragile bones and feeling tired.

If your BMI is below 18.5, this suggests that your weight may be too low.

There are lots of different reasons why you may be underweight:

  • feeling unwell
  • not finding time to make healthy, balanced meals
  • losing your appetite because you are stressed or worried
  • trying to lose weight

If your low weight is caused by your diet, changing your diet to a healthy balanced diet can help you achieve a healthy weight. You should aim to gain weight gradually by eating foods that are healthy and also high in energy. If you're concerned about being underweight visit the NHS website where you can find more information to help you.

Underweight older people

Losing weight is not a normal part of getting older.

You may be underweight because you’re not eating enough and not getting sufficient calories.

However, if you have lost weight suddenly or for no obvious reason you should see your GP to make sure you do not have an underlying medical cause for this weight loss.

Eating well can help you to gain weight and benefit from better mood and more energy. People who are a healthy weight have fewer GP visits and hospital admissions, faster recovery time and fewer other health complications including bone fractures if you fall.

If you’re underweight and your appetite has decreased you still need to get the energy and nutrients your body needs.

The NHS website has tips to help you eat if you’ve lost your appetite. It includes:

  • tips to boost your calorie intake
  • eating with friends and family
  • improving your appetite with exercise and moving more
  • having your meals delivered

The Greater Manchester Nutrition and Hydration programme raises awareness about malnutrition and hydration in older people and that losing weight is not a normal part of ageing. Their website includes tips and advice for eating and drinking well for older and / or more vulnerable people. You can also download the Eat, Drink, Live Well booklet which gives some tips to boost your appetite and some simple steps to add calories to meals and to make food preparation easier.