Overweight teenage boy eating too much fried food
On July 31, 2025, new research from the University of South Australia highlights a concerning trend among teenagers worldwide: an alarming combination of poor lifestyle choices that could lead to serious health issues in the future. The study reveals that when a cheeseburger costs less than a punnet of strawberries, the odds are stacked against healthy choices, particularly for teenagers.
Conducted across 73 countries and involving more than 293,770 teenagers aged 12-17, the study assessed the clustering of habits such as exercise, healthy food consumption, and screen time. The findings are stark:
- 85% did not get enough exercise
- 80% did not eat enough fruit and vegetables
- 50% regularly consumed fast food
- 39% had too many soft drinks
- 32% spent excessive time on screens
Overall, more than 92.5% of teenagers reported two or more unhealthy behaviors, increasing their risk of developing chronic diseases such as obesity, heart disease, and diabetes. Specifically, 7% of teenagers reported one unhealthy behavior; 30% had two; 36.5% had three; 21.5% had four; and 4.5% had five unhealthy behaviors. Across all WHO regions, less than 1% of teenagers exhibited no unhealthy behaviors.
Global and Regional Trends
The announcement comes as the South Australian government launches its new ‘LiveLighter’ campaign to tackle obesity. Lead researcher, UniSA’s Dr. Ming Li, emphasizes the importance of teenage years as a critical window for growth and development. “The teenage years are a critical window for growth and development – physically, mentally, and emotionally – and they set the foundation for long-term health,” Dr. Li explains.
However, the study found distinct differences between regions. Teenagers in higher-income countries, including the Americas and Eastern Mediterranean, were more likely to report a higher number of unhealthy behaviors, with 13% of teenagers in these regions recording all five risk factors. While Australian data was not specifically assessed, Dr. Li suggests that Australian teenagers would likely exhibit similar patterns to those seen in other high-income countries.
Societal Influences and Challenges
According to Dr. Li, these trends are influenced by broader societal shifts. “Some of what we see comes down to rapid urbanization, sedentary school environments, and limited access to safe recreational spaces, particularly in low- and middle-income countries,” Dr. Li notes. “On top of this, taste preferences, household income, and limited availability of fresh produce – especially in disadvantaged areas – make healthy choices harder to access and maintain.”
Despite the prevalence of unhealthy behaviors, the study also identifies protective factors that can mitigate risks. “When teenagers have supportive families and a supportive peer group, their risk of having four or more unhealthy behaviors reduces by 16% and 4% respectively,” Dr. Li says. “Similarly, food-secure households also reduce risk by 9%.”
Call for Systemic Change
The move represents an urgent call for tailored, multilevel strategies that go beyond individual choices to address social and environmental conditions. Dr. Li stresses the need for systemic action: “It’s clear we need systemic action – better school-based physical activity programs, urban design that gives teens access to green spaces, policies that make healthy food affordable, and limits on junk food marketing to children,” Dr. Li advocates.
“Ultimately, good health needs to be an easier, more accessible choice – not one that requires privilege, planning, and willpower,” Dr. Li concludes.
For more information or to arrange an interview with Dr. Ming Li, please contact Annabel Mansfield at +61 479 182 489 or via email at [email protected].
