Adolescence—long seen as a time of growth, energy, and possibility—is increasingly overshadowed by a stealthy threat: obesity. Around the world, more teens are carrying extra weight, and the implications go far beyond appearance. What might seem like “just extra pounds” during the teenage years can quietly set the course for chronic disease, mental health struggles, and escalating healthcare burdens later in life.
A worldwide epidemic in the making
Overweight and obesity among adolescents have reached alarming levels globally. According to the WHO, in 2022 there were more than 390 million children and adolescents aged 5–19 who were overweight, of whom 160 million were living with obesity—a dramatic increase since 1990. Data from UNICEF show that this is part of a broader shift in nutrition. The number of school-age children who are overweight has doubled worldwide, and obesity is increasing more rapidly than overweight. In fact, for the first time, obesity (9.4%) has overtaken underweight (9.2%) among children and adolescents aged 5–19.
This crisis spans the globe. In Southeast Asia and the Pacific alone, over 113 million young people are now overweight, with over 15% of children and adolescents affected in 30 of 33 countries, partly fuelled by aggressive marketing of ultra-processed foods. Meanwhile, in higher-income countries such as the United States, obesity has long been a major concern. Recent UNICEF data estimate that 21% of U.S. children and teens aged 5–19 are now obese.
In Nepal, the nutrition landscape is changing dramatically: a country once predominantly plagued by undernutrition is now facing an increasing burden of overweight and obesity among adolescents—a phenomenon often referred to as the “double burden” of malnutrition. Studies from Kathmandu detected 23.7% of adolescents as overweight or obese and 9.1% as underweight, highlighting that both extremes coexist.
Overall, economic development, rapid urbanisation, and changing dietary behaviours—including increased consumption of junk foods, sweetened beverages, and sedentary practices—are driving this upward trend. School type, parental income, and lifestyle practices are strongly associated. Research from Kaski district reveals that adolescents from higher-income families, or whose parents are involved in particular occupations, have higher odds of being overweight. Surprisingly, a recent cross-sectional study in Butwal showed that the overall prevalence of overweight among school-going teenagers was as high as 21.5%, especially among those from upper socioeconomic backgrounds.
These data indicate the urgent need for interventions worldwide that address not only continued undernutrition but also the emerging problem of excess weight—through school-based health education, policy action on food environments, and programmes promoting active, balanced lifestyles.
First adolescent mental health unit established in Nepal
Key factors driving the epidemic
· Dietary changes: Increased availability and accessibility of ultra-processed foods, sugary drinks, and fast food are prevalent across most regions. Studies show that adolescents who consume sugary drinks daily are 55% more likely to become overweight or obese compared to peers who rarely consume them. Globally, fast-food consumption among teens has increased by over 30% in the last decade, contributing to rising obesity rates.
· Sedentary lifestyle and screen time: Teenagers spend considerable time on smartphones, social networking sites, and video games, reducing physical activity. On average, adolescents spend 7–9 hours per day on screens. Research indicates that adolescents who spend more than three hours per day on recreational screen time have a 35–40% higher risk of obesity.
· Urbanisation and socioeconomic change: City living and increased family incomes, coupled with reduced active transportation such as walking or cycling, also contribute to decreased physical activity and increased weight gain.
· Obesogenic environments: Easy access to unhealthy foods, aggressive marketing to children, and limited safe spaces for play or physical activity exacerbate the problem. Studies show that for every additional fast-food outlet within a neighbourhood, the odds of adolescent obesity rise by 10–15%, and children exposed to frequent junk food advertising consume 30–40% more calories from unhealthy snacks than those with lower exposure.
Health ramifications of adolescent obesity
The consequences of teenage obesity extend far beyond the adolescent years:
· Metabolic and cardiovascular risks: Adolescents with obesity are at heightened risk of developing type 2 diabetes, fatty liver disease, MASLD, insulin resistance, and hypertension. Up to 23–50% of obese adolescents may already show early signs of such chronic conditions.
· Psychosocial effects: Obesity is associated with stigma, bullying, reduced self-esteem, depression, and anxiety. A U.S. study using data from the Youth Risk Behavior Survey (13,871 adolescents) found that adolescents with obesity had 1.65 times higher odds of attempting suicide compared to non-obese peers. In the same study, the odds of developing a suicidal plan were 1.27 times higher, and suicidal ideation 1.31 times higher among those with obesity.
Taking action
Prevention of adolescent obesity is a shared responsibility, involving families, schools, communities, and policymakers:
· At home: Promote healthy meals instead of processed foods; limit sugary drinks and encourage regular physical activity. Balance screen time with outdoor play and ensure adolescents get adequate sleep. Parents and caregivers should model healthy habits themselves.
· In communities: Provide safe areas for recreation, lead walking or sports groups, offer healthy cooking classes, and enhance access to fresh fruits and vegetables. Reducing the marketing of unhealthy foods to children can also help.
· In schools: Restrict the availability of sugar-sweetened drinks and snacks. Integrate physical activity into daily routines. Provide nutrition education and promote safe active commuting.
·Through policy: Strengthen food labelling by governments and local authorities, regulate marketing to children, provide subsidies for healthy foods, and support infrastructure for safe play and physical activity.
By working together, families, schools, and communities can help adolescents adopt active, balanced lifestyles, giving them the best chance to maintain a healthy weight and thrive into adulthood.
Act now—because the clock is ticking. The hidden consequences of adolescent obesity are very real but preventable. If current global trends continue, the burden of chronic disease will rise alongside associated economic and societal costs. By promoting increased physical activity, better eating habits, reduced screen time, and supportive environments, we can lay the foundation for a healthier, thriving, and fulfilling adulthood.
(The author is a Registered Public Health professional and Master’s student in Nutrition and Dietetics, University of New Mexico, US)
