What does Underweight mean?
Being underweight isn’t good for your health. Weighing too little can contribute to a weakened immune system, fragile bones and feeling tired.
Why are you underweight?
If you are underweight, think about why this might be.
- Have you felt unwell? There might be an underlying medical cause for your low weight, such as an overactive thyroid.
- Have you been finding it difficult to make time to have a healthy, balanced diet with regular meals?
- Have you lost your appetite, perhaps because you’re worried or stressed?
- Have you been trying to lose weight?
If you feel anxious or worried when you think about food or feel that stress or low self-esteem are affecting the way you eat, you may have an eating disorder.
Why being underweight could be a problem?
Being underweight isn’t good for you. It could cause:
- Nutritional deficiencies: If you’re underweight, it’s likely that you’re not consuming a healthy, balanced diet, which can lead to you lacking nutrients that your body needs to work properly. Calcium, for example, is important for the maintenance of strong and healthy bones. If you don’t get enough calcium, you risk developing Osteoporosis (fragile bone disease) later in life. If you’re not consuming enough iron, you may develop Anaemia, which can leave you feeling drained and tired.
- Weakened immune system: Your immune system isn’t 100% when you’re underweight, so you’re more likely to catch a cold, the flu or other infections.
- Fertility problems: Women who are underweight can find that their periods stop.
How to put on weight safely?
If the diet is the cause of your low weight, changing to a healthy, balanced diet that provides the right amount of calories for your age, height and how active you are can help you achieve a healthy weight. Aim to gain weight gradually until you reach a healthy weight. Try to avoid relying on high-calorie foods full of saturated fat and sugar – such as chocolate, cakes and sugary drinks – to gain weight. These foods can increase body fat instead of lean body mass and increase your risk of developing high levels of cholesterol in your blood. Aim for regular meals and occasional snacks.
A few tips to consider:
- Eat at least five portions of a variety of fruit and vegetables every day.
- Base your meal on potatoes, bread, rice, pasta or other starchy carbohydrates. Choose wholegrain where possible.
- Have some dairy or dairy alternatives (such as soya drinks and yogurts). Choose lower-fat and lower-sugar options.
- Include beans, pulses, fish, eggs, meat and other protein. Aim for two portions of fish every week – one of which should be oily, such as salmon or mackerel.
- Choose unsaturated oils and spreads, such as sunflower or rapeseed, and eating them in small amounts.
- Drink plenty of fluids. Try not to have drinks just before meals to avoid feeling too full to eat.
If you’re having foods and drinks that are high in fat, salt and sugar, have these less often and in smaller amounts. Try to choose a variety of different foods from the five main food groups. However, for those who need more specialized nutrition advice, consult your GP or a registered dietitian. Also, if you don’t eat meat, find out how to have a healthy vegetarian diet.
Tips to boost your calorie intake
If you’re trying to gain weight, eat foods that are not only healthy but also high in energy.
Try the following:
- For breakfast, porridge made with whole (full-fat) milk with chopped fruit or raisins sprinkled on top; or eggs on toast.
- Milkshakes are a great snack. Make them at home and take them to work or college. Fortify them with milk powder for extra protein and calories.
- For a healthier lunch, try a jacket potato with baked beans or tuna on top, which contains energy-giving starchy carbohydrates and protein.
- Peanut butter on toast makes a great high-energy snack.
- Yoghurts and milky puddings, such as rice pudding, are high in energy.
- Consume unsalted nuts.
- Try to limit the fruit and vegetable juices and smoothies to no more than a combined total of 150 ml a day.