You can check if your child is overweight or underweight using the NHS BMI calculator*. BMI tells us whether our weight is right for our height and because children are growing, their BMI is given as a centile. Health professionals may plot your child's growth on a growth chart.

Avoid weighing your child too regularly as weight can fluctuate daily and repeated weighing could cause anxiety for both you and your child. Speak to your GP or Health Visitor for further guidance. The NHS BMI calculator will show if your child is a healthy weight using the centile ranges below:

  • Underweight: on the 2nd centile or below
  • Healthy weight: between the 2nd and 91st centiles
  • Overweight: 91st centile or above
  • Very overweight: 98th centile or above

*The NHS BMI calculator is not appropriate for children under 2 years, seek advice from your GP or health visitor.

If your child falls above or below the healthy weight range this can affect their overall health and wellbeing, including mental health issues like low self-esteem and self-confidence.

Healthier Together North East and North Cumbria is a free website and app developed by local healthcare professionals to help parents keep their children safe and healthy, and have more information on ways you can encourage your children to have a healthy diet and healthy weight. Wellbeing for Life is a local service providing support with healthy eating, physical activity and more, both face-to-face within County Durham and online.

Underweight children

If there are any concerns with a child's poor weight gain or faltering growth, it is recommended to speak to their health visitor or GP, who may give advice and/or refer to a dietitian. As all children are different and reasons for poor weight gain vary, it is very important that the child is assessed by a healthcare professional. Individual advice can then be given, taking the child's weight, height and feeding history into account. If a child's weight is maintained but their height increases, their BMI will reduce to a lower centile.

Children in the underweight range, or with faltering growth, are eating/drinking less energy than their body needs. To help children become a healthier weight, families are usually advised to increase the child's energy (calorie) intake. It's important for children to continue to be active, and children who don't have enough energy may struggle with this.

One of the main strategies used to improve weight gain in children is food fortification. This involves adding calories (energy), protein and/or fats to foods without dramatically increasing the portion size of the meal or snack. This can also be called making the food more energy dense.

Foods which can added to meals or snacks to make them more energy dense include:

  • Full fat milk and dried milk powder
  • Cheese, yoghurt and cream
  • Margarine, oil and butter
  • Meat, fish and other protein sources
  • Nuts and nut butters
  • Avocado
  • Sauces e.g. mayonnaise, ketchup, pesto, sour cream, guacamole
  • Sugar, honey and jam

Where possible, try to aim to keep the diet balanced. It can be tempting to increase high sugar and/or ultra-processed foods in the diet. Small amounts of these foods can be included, but It is recommended they are added to balanced meals/snacks, rather than given by themselves e.g. adding chocolate spread to a slice of toast with banana, rather than a just giving a chocolate bar.

It is helpful to offer children 3 meals and 2-3 small snacks per day (making them energy dense where possible). Desserts and nourishing drinks are also an easy way to increase calories. Remember to take into consideration any allergies and choking risks.

Avoid force feeding your child. Children should be praised when eating well, but avoid negative comments or behaviours if your child chooses not to eat.

Some children may also need a nutritional supplement to boost their weight gain. This may be advised by their GP or dietitian.

Whilst your baby is breastfeeding or given formula milk, your healthcare professional may suggest increasing the volumes or frequency of feeding, top up feeds, increasing the concentration of formula and/or using a high energy formula.

Whilst your baby is weaning (from 6 months) you may be advised to increase both milk and solid foods.

Overweight children

Children that are overweight are more likely to become overweight adults and with this comes increased risks of other health conditions, like heart disease, diabetes and cancer.

To help your child become a healthier weight it's important to consider how your family could eat healthier, and move more. You may wish to speak to your child's GP or school nurse about their weight. As children are continuing to grow taller (pre-puberty), health professionals are likely to encourage maintenance of your child's weight. Maintaining their current weight means keeping their weight the same whilst they are growing taller, which will lower their BMI over time.

Children in the overweight range are eating/drinking more energy (calories) than they are burning off through activity, which causes them to slowly gain weight. To maintain their current weight, or slowly lose weight, it's important to use a combination of both eating healthier and moving more. Large, sudden weight losses are not recommended.

Listing reasons why you as a family are motivated to become healthier and reflecting on these, can help keep motivation high when trying to make lifestyle changes.

  • Consider portion sizes that you feed your child - food packaging usually shows the recommended portion size. You may find it easier to buy foods that are already in individual portions as children will tend to eat more if they are given a larger portion. It may be useful to read more about using your child's hand to measure a portion.
  • Eating together as a family at mealtimes makes them more enjoyable for children and eating the same meals shows them that you enjoy eating healthy meals too - children will copy your behaviour so it's important to make healthy changes as a whole family.
  • Eat healthy meals with a balance of food groups. Check out our information on Healthy Eating to learn more about the food children should be eating. Look for ways to reduce the amount of foods high in fat, salt and added sugar that your family eats.
  • Consider methods of introducing new foods for Fussy Eaters.
  • Move more. Look for new activities your family can do together to be more active like walking to school, going to the park or a family bike ride. Children should be active for at least 60 minutes every day. Physical activity is also good for children's confidence, sleep, social skills, coordination, concentration, overall health and more. Find out about sports and activities in County Durham and Darlington.
  • Consider limiting your child's screen time. Sitting around too much can increase your child's chances of putting on weight. Taking this approach as a family will set a good example for your child, and may also improve your family's sleep quality.
  • It can be challenging to talk to your child about their weight. Children can be unhappy with their weight and avoiding talking about it can give your child the impression that they can't talk to you about it. It's important to focus on the positives like what they can do to be healthier, and providing praise for the things they are doing well.
Interactive education