Underweight children aged 6-12

Children aged 6-12 are still growing, which means they need more energy (calories). If your child is underweight, they may not be getting enough calories.

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If you're concerned that your child is underweight or not growing normally, take them to see your GP. Low weight can occur for a number of reasons.

Your GP will weigh and measure your child and talk to you about what your child is eating. If there is a possible problem with your child's diet, your GP can give advice on what will help bring them up to a healthy weight, or refer your child to a dietitian.

Paediatric dietitian Jacqui Lowden, from the Manchester Children's Hospital, explains basic child nutrition and what to do if your child is underweight.

A healthy, balanced diet for children

"All children need energy and nutrients from a varied and balanced diet," says Jacqui.

If your child is underweight, it may be tempting to fill them up with high-calorie but unhealthy foods, such as sweets, cake, chocolate and sugary and fatty foods and drinks. However, it's important that your child gains weight in a healthy way, and this means eating a balanced diet.

Once they reach the age of five, you can start to make sure your child's diet is similar to the healthy, balanced diet recommended for adults (children under five need a diet that is higher in fat and lower in fibre than this). That means three meals a day and healthy snacks.

A balanced diet includes the following principles:

  • Eat at least five portions of a variety of fruit and vegetables every day.
  • Base meals on potatoes, bread, rice, pasta or other starchy carbohydrates. Choose wholegrain where possible.
  • Have some dairy or dairy alternatives (such as soya drinks and yoghurts). Choose lower-fat and lower-sugar options.
  • Eat some 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 and eat in small amounts.
  • Drink plenty of fluids – the government recommends 6-8 cups/glasses a day.

If you're having foods and drinks that are high in fat, salt and sugar, have these less often and in small amounts.

Try to choose a variety of different foods groups. Most people in the UK eat and drink too many calories, too much fat, sugar and salt, and not enough fruit, vegetables, oily fish or fibre.

Learn more about the different food groups and how they form part of a healthy, balanced diet.

Children's meals at home

"This is a good time to sit down and think about how your family eats," says Jacqui. "Do you take time for proper meals or do you rely on snacks and quick fixes? If so, that might be part of the reason your child isn't consuming enough calories."

Make time for a proper breakfast and dinner, and eat together as a family. Make mealtime a fun part of the day.

To help your child gain weight, increase their portion sizes at mealtimes until they have reached a healthy weight, especially for starchy foods such as bread, rice, pasta and potatoes. You can check how healthy their weight is using the healthy weight calculator.

Children's lunches

During the week, your child will eat lunch at school. It's impossible to monitor exactly what your child eats away from home, but you can help your child make healthy choices.

  • Talk to your child about the importance of a healthy and balanced diet.
  • Give your child prepaid school lunches, or a healthy packed lunch, instead of giving money that your child can spend on food.
  • Find out what the school's healthy eating policy is.

These days, school lunches have high standards and are more likely to meet a child's nutritional requirements compared with the average packed lunch. However, if you would prefer to make your child a packed lunch, make sure it is nutritionally balanced. A good packed lunch should include a starchy food; protein from meat, fish, eggs or beans; a milk or dairy food; and a portion of fruit and vegetables.

Below are some ideas to get you started:

  • Sandwiches with a filling of lean meat, tuna, eggs or cheese provide carbohydrates and protein.
  • Potato or pasta salad are tasty alternatives to sandwiches.
  • A carton of milk, a lower-sugar fruit yoghurt or piece of cheese will provide calcium, which is important for growing bones.
  • Cut vegetables into small segments to make them easier to eat. A small handful (about 30g) of dried fruit counts as one portion of their 5 A DAY.
  • Don't forget a drink. Water, milk or 100% pure fruit juice is best. Limit your child's consumption of fruit/vegetable juices and smoothies to a combined total of 150ml a day at mealtimes, as it can cause tooth decay. 

Get ideas for what to put in your child's school packed lunch.

Snacks for kids

If your child isn't consuming enough calories, you can boost their daily intake by providing healthier snacks.

On school days, you can provide a healthy snack for your child to eat at morning break.

Great snack ideas include:

  • small sandwiches with a protein filling, such as cheese or eggs
  • cheese and crackers or cheese on wholemeal or brown bread
  • yoghurt, which contains protein and calcium
  • other energy-dense foods, such as bananas and avocados

Keep your child active

Physical activity burns calories your child has consumed. But even if your child is underweight, it's still important that they're physically active.

Physical activity helps them develop strong, healthy bones and muscles. It's a crucial part of how they learn about themselves and the world. And, best of all, it’s great fun.

Children over five should do a minimum of 60 minutes of at least moderate-intensity activity each day. But the amount of physical activity your child should do may be different if they're underweight. Your GP, practice nurse or school health visitor can advise you on this.

Find ideas on how to get active with your child.

Monitor your child's progress

If you provide a healthy diet using these guidelines, you should see your child’s weight and growth improve.

Keep regular records of your child's height and weight, and take your child back to your GP to check that their weight gain is happening as it should. Once your child has reached a healthy weight, their diet may need adjusting so that they don't become overweight.

Page last reviewed: 14/11/2014

Next review due: 31/05/2017


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