If your child is a healthy weight, there's lots you can do as a parent to help them stay a healthy size as they grow. Research shows children who stay a healthy weight tend to be fitter, healthier, better able to learn, and more self-confident. They're also much less likely to have health problems in later life.

Children whose parents encourage them to be active and eat healthily are more likely to stay a healthy weight and grow up healthy. Check their BMI every now and then using our BMI calculator for children and teenagers to see how they are growing over time.

Be a good role model

One way to instil good habits in your child is for you to be a good role model. Children learn by example. You can encourage your child to be active and eat well by doing so yourself. Set a good example by going for a walk or bike ride instead of watching TV or surfing the internet.

Playing in the park or swimming with your children shows them being active is fun. It's also a great opportunity for you all to spend time together. Any changes you make to your child's diet and lifestyle are much more likely to be accepted if the changes are small and involve the whole family.

Get active

School-aged children need about 60 minutes of physical activity a day for good health.

Activity does not need to be all at once, it can be spread throughout the day. It could include riding a bike, skateboarding, walking to school, skipping, swimming, dancing and martial arts.

Children under 5 years old need more than 3 hours' activity a day. It can take the form of active play, such as ball games, chasing games like "it" and "tag", riding a bike or scooter, using playground swings, climbing frames and see-saws. Activities should make children breathe faster and feel warmer. Walking or cycling short distances instead of using the car or bus is a great way to be active together as a family. And you'll save money, too.

Child-size portions

There's very little official guidance on precisely how much food children require, so you'll need to use your own judgement on child-size portions.

A good rule of thumb is to start meals with small servings and let your child ask for more if they're still hungry. Avoid making your child finish everything on the plate or eat more than they want to.

Use smaller plates for younger children, as adult-size plates could encourage them to eat oversized portions. It may also help if you encourage your child to eat slowly and have set mealtimes. You can use mealtimes as an opportunity to catch up on what's happened during the day.

Explain to your child how to get the balance of their diet right using the Eatwell Guide. It shows how much we should all eat from each food group.

Eat a healthy balanced diet

Children, just like adults, should aim to eat 5 or more portions of a variety of fruit and vegetables every day. They're a great source of fibre and vitamins and minerals. Getting 5 A Day should not be too difficult. Almost all fruit and vegetables count towards your child's 5 A Day, including fresh, tinned, frozen and dried. Juices, smoothies, beans and pulses also count.

Be aware that unsweetened 100% fruit juice, vegetable juice and smoothies only count as a maximum of 1 portion of their 5 A Day. For example, if they have 2 glasses of fruit juice and a smoothie in 1 day, that still only counts as 1 portion. Their combined total of drinks from fruit juice, vegetable juice and smoothies should not be more than 150ml a day, which is a small glass.

If they have 150ml of orange juice and a 150ml smoothie in 1 day, for example, they'll have exceeded the recommendation by 150ml. When fruit is blended or juiced, it releases the sugars. This increases the risk of tooth decay, so it's best to drink fruit juice or smoothies at mealtimes.

Discourage your child from having sugary or high-fat foods like sweets, cakes, biscuits, crisps, chocolate, some sugary cereals, and sugar-sweetened soft and fizzy drinks. These foods and drinks tend to be high in calories. Aim for your child to get most of their calories from foods like fruit and vegetables, and starchy foods like bread, potatoes, pasta and rice (preferably wholegrain versions).

They should also have some beans, pulses, fish, eggs, meat and other protein foods, and some dairy or dairy alternatives. And swap sugary soft drinks, juice and flavoured milks for water, lower-fat milks and diet, sugar-free or no added sugar drinks.

Less screen time and more sleep

Help your children avoid sitting and lying around too much, as it makes it more likely for them to put on weight. Limit the amount of time your child spends on inactive pastimes such as watching television, playing video games and playing on electronic devices.

There's no hard and fast advice on how much is too much, but experts say children should watch no more than 2 hours of television each day. And remove all screens (including mobile phones) from their bedroom at night.

It also helps children stay trim if they sleep well. It's been shown children who don't have the recommended amount of sleep are more likely to be overweight. The less children sleep, the greater the risk of them becoming obese. Lack of sleep can also affect their mood and behaviour.