Childhood obesity: is your child overweight?

Published November 2024 | 5 min read 
Expert contributors Dr Terri-Lynne South, chair of obesity management at the Royal Australian College of General Practitioners; Edwina Ekins, clinical practising nutritionist 
Words by Angela Tufvesson

Childhood obesity is on the rise in Australia. Here’s how to tell if your child is overweight – and what to do about it.

Are you worried your child seems to be at a less healthy weight than his or her peers? Perhaps they’re not as active as they used to be, or comments from other parents or children are starting to creep in. 
 
With one in four children and adolescents above a healthy weight range for their age, a growing number of Australian parents are concerned about obesity and childhood health.  

Overweight children and young people are more likely to develop problems, like diabetes and heart disease, as a result of their weight, even before they enter adulthood.  

Figuring out if your child is overweight or obese isn’t as simple as observing them or having them hop on the scales, explains Dr Terri-Lynne South, chair of obesity management at the Royal Australian College of General Practitioners. 

“You can't tell if your child is overweight or obese just by looking at them,” she says. “And it isn’t about measuring a single parameter but monitoring growth over time.”

Childhood obesity in Australia and globally 

Childhood obesity is a major public health issue in Australia and around the world, with the global prevalence increasing dramatically from 8% in 1990 to 20% in 2022, according to the World Health Organisation. 

One in three children in England and across Europe are overweight or obese by the time they finish primary school. Almost 20% of children and young people in the US are obese.  

Once considered a high-income country problem, childhood obesity is now on the rise in low- and middle-income countries. Almost 30% of children in China were overweight or obese in 2022 and the proportion is projected to rise to almost 40% if current trends continue.  

In Australia, 27% of children aged five to 17 years are overweight or obese.  For those children living in outer regional and remote Australia, that figure rises to 28.8%.   

Childhood obesity is often associated with poorer health and wellbeing, worse performance at school and increased risk of being overweight in adulthood.  

“We are comparable with other Western countries – we’re all struggling with increasing obesity rates,” says Dr South.  

The National Obesity Strategy 2022-2032 in Australia states obesity in children increases the risk of chronic disease, and can affect both their growth and development, as well as their life opportunities. Children can also experience weight stigma and weight-based teasing and bullying. This can have an impact on mental wellbeing, peer relationships and self-confidence in being physically active, says Dr South. “The difficulties of living in a larger body can affect mental health.” 

If you feel your child may be suffering silently, HCF members who have hospital or extras cover can access Calm Kid Central* at no cost, an online educational and support program helping kids aged four to 11 manage their big feelings and emotional challenges. The program provides access to an online forum of experienced child psychologists who can answer your questions within 48 hours, as well as tools and resources to help you support your child. 

What is childhood obesity? 

Being overweight or obese means being above a healthy body weight. Obesity is usually defined by body mass index (BMI) – a measure of body fat based on height and weight. For children, this is plotted on a growth chart and compared to other children of the same age and gender.  

A child with a BMI-for-age between the 85th and 95th percentile – that is, higher than 85% of children of the same age and gender – is considered overweight, while the 95th percentile or greater is considered obese. 

Because children are growing and expected to gain weight, Dr South says it’s crucial to monitor BMI over time. 

“It needs to be in the context of not just a single parameter, but growth over time,” she says, adding it’s important to recognise children grow and develop at different rates. 

Indeed, there’s growing concern BMI doesn’t always take into account body frame or muscle mass. 

Research suggests a waist circumference to height ratio can better distinguish muscle mass from fat mass and provide a more accurate measure of obesity in children and adults. The World Obesity Federation has also stated that obesity should no longer be talked about in terms of body size and body weight. 

Causes of childhood obesity

For most children, obesity happens because they gradually take in more energy from eating and drinking than the amount of energy their bodies use to grow and play. This is complicated by a complex web of social, economic, environmental and genetic factors – like access to healthy food, parents’ education levels and family history of obesity. 

Dr South says some of the big changes to the way we live that have occurred in the past few decades correlate with rising childhood obesity rates.  

“Our genetics haven’t significantly changed in the last 30 years, but our environment has dramatically,” she says.  

While things like underlying medical issues (hormone imbalances, genetic syndromes, depression, asthma) and parents’ smoking do play a role in childhood obesity, Dr South is keen to emphasise that environmental changes to diet and exercise patterns are most significant. 

“It's little things like how children get to school. There's less walking and biking to school than 30 years ago. There's less outdoor play than 30 years ago,” she says. “There's more sedentary time and screen time in regard to recreation.”  

Plus, she says, there’s been an “explosion of ultra-processed foods” in supermarkets and changes to the way families eat. “We’re eating more takeaways, pre-prepared meals and snacks.” 

How to help children with obesity  

If you’re concerned about your child’s weight, Dr South recommends seeing your doctor regularly.   
“It’s really important to check in with your GP, and potentially do so over time, to be able to intervene earlier rather than later if there’s a problem,” she says.  

Treatment options include lifestyle intervention, intensive dietary approaches and improving quality of sleep. 

Parents can encourage healthy eating, better sleep hygiene and exercise behaviours that help children maintain a healthy weight as they grow.  

Qualified clinical practising nutritionist Edwina Ekins recommends these simple strategies: 

• Lead by example. “Role model healthy behaviours and talk about ‘health’ not ‘weight’. Eat at the table instead of in front of the TV. Go for regular walks or play a sport.” 
• Instigate a sleep routine. “This includes eating early to allow for digestion, putting kids to bed and waking up at the same time, and making sure the bedroom is not too hot or cold (between 17 and 19 degrees).” 
• Get clever with food. “Focus on fruits, vegetables and whole foods as much as possible. Sometimes it takes children up to 10 times of trying a food before they like it. If your child only eats white bread, you might do one side of the sandwich white bread and one side of the sandwich grain bread – just keep putting it out there.” 
• Create opportunities to be active as a family. “Go to the beach and throw a ball, bushwalking, outdoor play, walking the dog, family dance parties, bike riding, going to the zoo or go to the park to run around. As a parent, you need to facilitate the activity.”  
• Avoid using snacks as a reward. “This creates an association between eating and emotions, which can lead to the habit of eating for comfort in response to emotions rather than for hunger. Usually reward foods are treat foods that are high in sugar, fat and salt like an ice-cream. This can encourage a preference for unhealthy foods as these foods are seen as special or desirable. Instead, go scootering in the park or invite a friend over as a reward for positive behaviour.”  

Edwina also points out the importance of creating a balanced routine for children that includes limited screen time, regular physical activity, enough rest time and social connection with family and friends.  
 
The government recommendations for children aged two to four is at least 180 minutes of physical activity, including energetic play, and no more than 60 minutes screentime. For children aged five to 17, at least 60 minutes a day of moderate to vigorous intensity physical activity is recommended, and no more than two hours a day of screen time for entertainment (for example, television, seated electronic games and computer use).

Medication for childhood obesity

While Ozempic (which is primarily used to lower blood sugar levels in diabetes patients) has been approved by the American Association of Paediatrics for use in children as young as 12 in America, here in Australia Ozempic is still not approved for the treatment of weight loss in adults, let alone children.  

The official Ozempic website states: “it is not known if Ozempic is safe and effective for use in children under 18 years of age”.

Interestingly, a new strategy to treat obesity in children has involved the use of apps and digital health (known as mHealth). A recent study found mobile apps, web-based tools, portable monitoring devices and even pedometers can be used to effectively prevent weight gain in children and aid in the treatment of childhood obesity. Rather than a significant change in BMI levels, the study suggests the main benefit of mHealth is encouraging behavioural change.  

Medications and treatments aside, Dr South recommends checking in with your GP, increasing the amount of exercise children undertake, streamlining their nutritional intake and improving their sleep as a first port of call.   

In extreme cases, and where the above measures have failed, bariatric surgery, like gastric bypass, may be considered. 

Need help now? 

If you want to speak to someone for support, these services can help: 
Butterfly Foundation 1800 33 4673
Kids Lifeline 1800 55 1800
Youth Beyond Blue 1300 224 636 

Helping your family stay healthy 

We’ve partnered with Ethos Health to bring our members Healthy Families for Life and Healthy Teens for Life, which are resources to support kids, from birth to teens, to develop positive nutritional habits for growth and development, and reduce the risk of chronic conditions in their future. Eligibility criteria applies^{^}.   

Eligible HCF members can also access telehealth consultations through our partnership with GP2U, an online video GP service. All HCF members with health cover can access a standard GP consultation (up to 10 minutes) for a fee of $50. 

For children with physical limitations or injuries, eligible HCF members can claim 100% back⁺ on physio visits for their children to help improve mobility, strength and overall physical health.