Obesity in children

Expert reviewer, Dr Edward Gaynor, Paediatrician
Next review due June 2020

Children need a healthy, balanced diet that gives them enough energy to grow and develop. But if they regularly take in more energy (calories) than they need, and don’t do enough physical exercise, they’ll put on too much weight.

Children who are very overweight and have too much fat in their body are classed as being obese. If your child is obese, they’re more likely to develop serious health problems later in life, such as diabetes, heart problems and even cancer.

An image showing a little girl lying in the grass

Is my child obese?

Children are all different shapes and sizes. Boys are different to girls and your child will grow and develop at their own rate. This constant change and variation can make it hard to know if your child is a healthy weight.

Dr Edward Gaynor, Paediatrician and Clinical Fellow at Bupa UK says: “It’s not always easy to know if your child is a healthy weight – especially if they are quite young. However, your child may be at risk of being overweight if you notice any of the following:

  • they regularly eat the same size food portions as yourself or an older sibling
  • they wear clothes made for older children because they fit better
  • they struggle to keep up with their friends when playing

Your child may be completely healthy, but if you’re concerned about their weight or think they could be at risk of being overweight, take them to see the GP. They’ll be able to confirm if your child is the correct weight for their age, height and gender.”

How the GP works out if your child is a healthy weight

Your GP or health visitor will use a calculation to work out your child’s body mass index (BMI) – this calculation is based on their height and weight. For adults, BMI falls within specific ranges, which indicate whether you are, for example, overweight, underweight or a healthy weight. You can find out more about these reference values on our healthy weight for adults page. But because children are still growing and their height, weight and body fat change a lot, these reference values can’t be used.

Instead, specialists collect data on weight, height and age for a large number of children and use this as a reference to develop charts, called BMI centile charts. These can then show whether children are under or overweight for their age by comparing their BMI against other children of the same age and gender. Your GP or health visitor is likely to be concerned if your child’s BMI is in the top 15 percent of BMIs collected for children their own age and gender. Children are seen as overweight if their BMI is equal to, or above the top nine percent of BMIs collected: Your child is obese if their BMI is in the top two percent.

Your GP or health visitor will use these charts to assess your child and check for other health conditions related to being overweight or obese. If they think there’s an issue with your child’s weight, they’ll ask about their diet and how active they are. They may also ask about any problems they have that may be caused by their weight, such as physical difficulties, teasing or bullying.

Lifestyle changes

The best way to tackle obesity in children (and adults) is to make lifestyle changes. If your child is seriously overweight or obese, they’ve been taking in more calories than they’re using up. You’ll need to make changes to their daily routine – the foods they eat and the amount of activity they do.

Think about changes you can make as a family to adopt healthier eating habits and become more active. Working together with your child or as a family is likely to be more successful long term as it will help you all make permanent changes to your lifestyle.

It’s also important for you to be a good role model. Children are very good at copying adults and if they see you eating well and exercising more, they’re more likely to join in.

To encourage your children, try setting goals and giving rewards and praise when they meet them. Choose smaller goals to start with, so that they can achieve them reasonably easily and are encouraged to carry on. Remember not to make rewards food-based though.

Food and drink

Your doctor may ask you to keep a diary of your child’s food and drink. A diary can help you to see exactly what they are eating. In turn, this can help you to see where to make changes. Don’t forget to include snacks.

Here are some tips to help your family eat more healthily.

  • Increase the amounts of vegetables, fruits and grains in your diet and cut down on fatty, salty and sugary foods.
  • Cut out sugary drinks altogether – offer water, semi-skimmed milk drinks (for over fives) or diluted fruit juice in moderation.
  • Add extra vegetables, beans or lentils to soups, stews, casseroles and pasta sauces.
  • If you’re meat eaters, choose more chicken and fish and less red and processed meat.
  • Serve smaller portions and check packaging for number of recommended servings. Using smaller plates may help – dinner plates we use today are much bigger than they were 20 or 30 years ago. If you have a toddler, find out more about how much your toddler should be eating.
  • Sit down to eat as a family as often as you can and involve children in planning and preparing meals. You can set a good example and they can learn about healthy eating.

Dr Edward Gaynor, Paediatrician and Clinical Fellow at Bupa UK says: “It’s important not to put your child on a diet that might affect the amount of nutrients and energy (calories) they need to develop and grow. Helping them to have a healthy, balanced diet and do enough physical activity is the safest way to help your child achieve or maintain a healthy weight”

Physical activity

Children over the age of five need to do at least 60 minutes of moderate to vigorous physical activity every day. This can be all in one go or over a number of sessions of 10 minutes or more.

Here are some tips to help your child get active.

  • Try building activity into everyday life, such as walking or cycling to school and using stairs instead of the lift.
  • Involve your children in family jobs, such as walking the dog, washing the car or some gardening.
  • Encourage your child to join classes or clubs for activities they enjoy, such as dancing, swimming or football.
  • Take part as a family: in walking, cycling, dancing or playing sports.
  • Cut down on the amount of time your child spends watching television or using a computer. Try to limit this to less than two hours a day or 14 hours a week.
  • Make sure your child gets enough sleep – increasing physical exercise can help with this. Did you know that school-aged children (6–13 years) should get between nine and 11 hours sleep each night?

Will my child be referred to a specialist?

Making changes to your child’s lifestyle is the most important way to combat obesity. Your GP may refer your child to see a paediatric dietitian, a doctor who specialises in child nutrition and diet. Your child’s dietitian will come up with a plan that's tailored to your child based on their age and BMI. Losing weight isn’t always advisable in children because they are still growing. Your dietitian may suggest that you aim to keep your child’s weight the same. As your child grows taller and their weight stays the same, their BMI will improve.

The GP may suggest that you and your child join a local programme to help them reduce weight and increase exercise. These programmes can also help you to learn more about diet and nutrition and to support and motivate your child.

Your GP may also suggest that your child see a paediatrician (a doctor who specialises in child health). This may be because they suspect that there’s a medical condition that is helping to cause your child’s weight problems. Or it may be because they have a medical condition that is being caused or made worse by their weight.

Can my child have medicines?

Medicines for weight loss are not recommended for children under 12. There’s a medicine called orlistat that may help children who are 12 and over to lose weight. It works by stopping fat from your diet being absorbed from the gut. However, it’s used very rarely and can only be prescribed in a specialist clinic. Your doctor will only prescribe orlistat if your child is very obese and has other health problems caused by their weight.

Can my child have surgery?

Weight-loss surgery for children is very rarely done and never for younger children. Your child’s doctor will only suggest it if you’ve tried everything else and nothing has worked. To be considered for surgery, your child will need to:

  • have been through puberty
  • be very obese
  • have other health problems related to their excess weight

Your doctor will discuss your child’s treatment choices with you.

What causes obesity in children?

There are a number of different things that can cause obesity in children:

  • eating a poor diet, such as large amounts of high-fat and sugary foods, or portion sizes that are too large
  • inactivity, for example, not doing enough exercise and spending too much time watching television or in front of a computer
  • lack of sleep, which can alter hormone levels and increase appetite
  • genetic (inherited) conditions, although these are rare

Your lifestyle when you’re pregnant and in early motherhood may also affect your child’s weight. For example, poor diet in pregnancy is linked to obesity in later life, while breastfeeding may reduce the chance of obesity. If you’re obese, your children are also more likely to be obese. This may happen because you share the same eating or activity habits, or a combination of both. For more information, see our FAQ: Your lifestyle and your child’s weight.

What complications could my child get?

If your child is overweight or obese, they are more likely to develop serious health problems in the future. Your child may be at risk of osteoarthritis, asthma, heart disease and stroke and some cancers, including bowel, breast, womb and prostate cancer.

Sometimes, damage happens in childhood, such as the development of flat feet, which can make walking painful. Your child might also be affected by:

Obesity can also affect your child’s emotional and mental health. Your child may have low confidence or self-esteem, which may lead to depression.

Frequently asked questions

  • There are some medical conditions that can cause obesity in children, but these aren't very common. They include the following:

    • genetic conditions such as Prader–Willi, Cohen and Bardet–Biedl syndromes
    • hormonal conditions, for example, Cushing's syndrome and hypothyroidism

    If your child does have an underlying medical condition, they’ll usually have other symptoms in addition to being overweight.

    Most children become overweight or obese because they take in more energy (calories) than they need, or aren’t active enough.

    If you’re worried that your child is overweight, contact your GP, your child’s school nurse or health visitor for advice.

  • There’s evidence that suggests your health, and choices you make when you’re pregnant, when your baby is born, and during their childhood, may affect your child’s weight.

    More information

    It’s very important to look after yourself when you’re having a baby. A poor diet when you’re pregnant is associated with an increase in your child’s risk of being severely overweight (obese) later in life. Being overweight when you’re pregnant and gaining a lot of weight during pregnancy are both linked to children being overweight and becoming obese in adulthood. Being overweight also increases your risk of developing diabetes while you’re pregnant (gestational diabetes). This can also lead to your child becoming overweight or obese in later life.

    Breastfeeding your baby can help to reduce the risk of them becoming overweight as they grow up. Breastfeeding has a number of health benefits for you and your baby, but it may not always be an option for every new mother. Talk to your midwife or health visitor about the benefits of breastfeeding, and if you're having any problems.

    The most important way that you can influence your child’s health is by being a good role model. A child who has parents who are obese is more likely to be obese themselves. Eating a healthy diet and being active will encourage them to do the same.

    For more information on encouraging good diet and exercise habits in your children, see our section on Lifestyle changes.

  • Children can sometimes be fussy eaters and it can be a challenge to get them to try new things. This is understandably a worry for parents, who know they need a balanced diet to help them grow and stay healthy.

    The foods they eat should include fruit, vegetables, starchy foods and protein. Encourage your child to choose a variety of foods from an early age. This will help them to get all the vitamins, minerals and nutrients they need.

    There are a number of ways you can introduce new foods in a fun way and make meals healthier. Here are some suggestions:

    • involve your child in preparing and buying food as it will help them to get interested in cooking and different foods
    • make your meals a social occasion and eat together as a family
    • think about how you present food to your children and make it fun
    • cook your children’s food using less fat by grilling, baking or steaming and cut the fat off meat before serving
    • replace foods like fish fingers with a portion of oily fish, such as sardines or salmon

    • Did you know: boys can have up to four portions of oily fish a week, but girls should stick to just two portions?

    • encourage your child to eat more fruit and vegetables by offering them a variety each day (either cooked or raw) – it’s not just fresh fruits that count, dried fruit and juices also count towards your child’s daily portions
    • make small changes to introduce new foods gradually, and remember that children often need to try a new food several times before they take to it
    • limit unhealthy snacks, such as cakes and biscuits – keep them out of sight or don’t buy them

    These are just a few suggestions to start you off. For more ideas, see our blog: Making food fun for fussy eaters.

  • The UK has one of the highest rates of childhood obesity in Europe. In 2014, one in every three 10 year olds and more than one in every five four year olds in England were overweight or obese. Worldwide, over 42 million children under five were overweight in 2013. If the current trends continue, the number of overweight or obese young children will increase to 70 million by 2025.

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  • Reviewed by Laura Blanks, Specialist Health Editor, Bupa Health Content Team, June 2017
    Expert reviewer, Dr Edward Gaynor, Paediatrician
    Next review due June 2020.

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