A growing concern: Nearly three-quarters of U.S. adults live with overweight or obesity

Nearly three-quarters of adults in the United States now live with overweight or obesity, according to a major study published in The Lancet. This alarming trend underscores the growing burden of weight-related conditions, including Type 2 diabetes, high blood pressure, heart disease, and reduced life expectancy. The findings also highlight the economic strain on the nation’s healthcare system, with obesity-related costs projected to reach up to $9.1 trillion over the next decade.

The study traces a striking rise in obesity rates nationwide since 1990, when just over half of adults were classified as having overweight or obesity. Researchers found that these conditions are affecting individuals at increasingly younger ages, with more than one in three children now living with overweight or obesity. Without effective intervention, the number of people affected is projected to rise to nearly 260 million by 2050.

“This is an epidemic,” said Dr. Marie Ng, an affiliate associate professor at the Institute for Health Metrics and Evaluation at the University of Washington School of Medicine and co-author of the study. The paper’s authors called for sweeping reforms, arguing that current policies have failed to adequately address the crisis. “It’s going to require a lot more attention and a lot more investment than we are currently giving the problem,” said Dr. Sarah Armstrong, professor of paediatrics and population health sciences at Duke University, who was not involved in the research.

The study used body mass index (BMI) to define overweight as a BMI of 25 or higher and obesity as a BMI of 30 or higher. While acknowledging the limitations of BMI as a measure—such as its inability to capture variations in body composition—it remains a practical tool for analysing body fat trends at the population level. The data reveal that rates of obesity have doubled among adults since 1990, affecting over 40% of adults by 2021. Among young women aged 15 to 24, the prevalence nearly tripled during the same period, reaching 29%.

Children and adolescents are particularly vulnerable to the long-term effects of obesity. Almost half of all teens and young adults aged 15 to 24 now live with overweight or obesity, compared with 29% in 1990. Experts are especially concerned about the rise in obesity among children, who are more likely to develop chronic conditions such as high blood pressure, high cholesterol, and Type 2 diabetes. “We’re seeing these conditions emerge more commonly while children are still children,” said Dr. Armstrong. Additionally, obesity during childhood is strongly linked to persistent obesity and chronic health problems in adulthood.

The study highlights the multifaceted drivers of obesity, including the widespread availability of ultra-processed foods, barriers to accessing fresh produce, and sedentary lifestyles. Social determinants of health—such as food insecurity, transportation challenges, and income inequality—further exacerbate the issue, particularly in Black, Hispanic, Indigenous, and low-income communities. Dr. Ng emphasised that addressing these structural factors is critical. “We recognise a lot is beyond the individual and beyond what can happen in the exam room,” said Dr. Sarah Hampl, professor of paediatrics at Children’s Mercy Kansas City and the University of Missouri-Kansas City School of Medicine.

At the individual level, interventions may include lifestyle modifications, medication, or bariatric surgery, though not all individuals will require every treatment. However, access to effective options remains a significant challenge. Health insurance often does not cover evidence-based interventions, such as intensive health behaviour programmes, GLP-1 receptor agonist medications like Wegovy and Zepbound, or bariatric surgery. While these newer drugs show promise, their high cost and uncertain long-term effects raise questions about their accessibility and sustainability as widespread solutions. “They’re not going to be the magic silver bullet to address the problem,” Dr. Ng cautioned.

Structural reforms are essential to reversing these trends. Policy measures such as subsidies for healthy foods, taxes on sugar-sweetened beverages, and stricter regulations on food marketing could significantly influence population-wide dietary behaviours. However, implementing such measures would require coordinated efforts across local, state, and federal levels.

While the rate of increase in obesity prevalence has begun to slow, the sheer magnitude of the epidemic remains concerning. Dr. Ng noted that with rates approaching 80% among adults, the problem has reached a saturation point. “If it’s reaching that level, there really isn’t much further it can go,” she said.

This research serves as a wake-up call for policymakers, healthcare providers, and communities. Obesity is a complex condition, influenced by genetic, physiological, environmental, and social factors. Tackling it will require comprehensive strategies that go beyond individual responsibility, focusing on systemic changes and equitable access to resources and treatments. Without such efforts, the health and economic toll of obesity will continue to escalate, with dire consequences for future generations.