New World Health Organization guidelines released in October reveal that 400 million children and adolescents aged five to 19 were overweight in 2024, with the prevalence climbing from eight percent in 1990 to 20 percent today.
Rising teen obesity worldwide
In Canada, Dr. Sanjeev Sockalingam, a medical psychiatrist and scientific director of Obesity Canada, is leading programs that target youth carrying excess weight and training health-care providers to recognize the underlying drivers.
He emphasizes that obesity is no longer a simple matter of “getting to your best weight or a magic number on the scale—it’s about untangling the complexity of chronic disease for each individual.”
According to Dr. Sockalingam, early intervention that incorporates emerging science, medication, and lifestyle support could curb the cascade of complications that typically emerge later in life.
Dr. Sockalingam’s career has blended physical and mental health care. He observed early on that metabolic disorders such as obesity often underlie liver disease and psychiatric conditions, prompting integrated treatment models at Toronto hospitals, including SickKids.
In his mental-health clinics, he found a bidirectional relationship: obesity can worsen mental health, while anxiety or depression can lead to weight gain, shaping his research and clinical approach for vulnerable youth.
Support groups he runs have highlighted teenagers’ resilience despite stigma. “Youth have had to deal with so much stigma and discrimination, and the resilience that they have to continue to seek help even when they were getting [outdated] recommendations,” he says of the push to exercise more.
While newer medications such as GLP-1 receptor agonists offer hope, they are not a stand-alone solution. Dr. Sockalingam warns that these drugs bring side effects and require careful discussion to frame obesity as a chronic condition rather than a quick fix.
Genetic factors also play a role; hereditary traits influence hunger centers and reward pathways, making some individuals more susceptible when exposed to an environment rich in calorie-dense foods.
Beyond diet, lifestyle elements like poor sleep, excessive screen time, and limited physical activity interact with biology, further increasing risk among teens.
Family habits matter, too. Exposure to nutritious foods, attitudes toward eating, and the rise of mood and anxiety disorders can predispose adolescents to weight gain. “If we don’t treat depression or anxiety, people are more likely to develop obesity, and if we treat it, we must be informed that there are some treatments that might predispose someone to developing obesity,” he notes.
The WHO guidelines emphasize that obesity is a complex, chronic condition requiring early intervention, behavioral and psychological support, and, in some cases, medical treatment.
Assessment and Intervention Strategies
Clinicians are urged to first recognize personal and systemic biases that affect how teens perceive care, especially when stigma around body size interferes with open dialogue.
Assessment should cover both physical markers, such as early signs of diabetes, high cholesterol, or hypertension, and mental-health screening to gauge engagement and identify barriers.
Social determinants like socioeconomic status, housing stability, and access to healthy foods also shape a teen’s ability to adopt healthier habits.
Medication options now include metformin and, in trials, GLP-1 agonists like semaglutide, which have demonstrated sustained weight loss and additional health benefits in adolescents aged 12 to 18.
These drugs are not without risks; gastrointestinal side effects mirror those seen in adults, and adherence requires ongoing education for both patients and families.
