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CNN  — 

In a little over two decades, almost 260 million people in the United States are predicted to have overweight or obesity, according to a new study.

The study, published in the medical journal the Lancet, is one of the first to project what the nation’s obesity epidemic will look like as far out as 2050. Specifically, it suggests that 43.1 million children and adolescents and 213 million adults will have overweight and/or obesity. In 2021, 36.5 million children and adolescents and 172 million adults had overweight and obesity.

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The new forecast would mean hundreds of millions of people in the US could be facing health complications associated with a high body mass index or BMI, including diabetes, cancer, heart problems, breathing issues and mental health challenges.

The health costs of obesity in this country are substantial, the study notes. In 2016, health care costs attributed to obesity alone were between $261 billion and $481 billion.

Obesity and overweight – defined as a BMI over 30 or between 25 and 29.9, respectively – are among the fastest-growing risk factors for an early death or disability in the United States, studies show.

To make the new forecasts, researchers at the Institute for Health Metrics and Evaluation at the University of Washington created a model to determine overweight and obesity trends using historic data from 134 unique sources, which they say included all major national surveillance survey data.

The study notes that overweight and obesity have been a growing problem for the United States for years. Obesity rates for adults and older adolescents doubled over the past three decades, and the prevalence of obese or overweight US women ages 15 to 24 increased faster than men from 1990 to 2021.

“Obesity is at a crisis point throughout the USA,” said Dr. Marie Ng, co-author of the study and an affiliate associated professor with the Institute for Health Metrics and Evaluation.

The large number of young people with obesity is of particular concern. Studies show that young people who have obesity or overweight are significantly more likely than those at average weight to have weight problems later in life.

The study noted that some regions of the country are more likely to be affected, with Southern states having a disproportionately larger population with obesity. States with the highest prevalence of obesity now will continue to have high numbers including Oklahoma, Alabama, Arkansas, Mississippi, Texas, West Virginia and Kentucky. Compared with 2021, the largest increases are expected in Colorado and New Mexico.

Specifically, the study showed that in Texas, more than half of all adolescent males ages 15 to 24 have obesity or overweight. In Mississippi, two-thirds of older adolescent females have overweight or obesity. In Mississippi, 80% of adult women have overweight or obesity.

The researchers note that their study has some limitations. Trends could change, so past trends may not be what happens in the future. Because of a lack of data, the researchers also weren’t able to project obesity levels for children at the state level.

Additionally, data on overweight and obesity is limited because it is typically based on BMI, a measure that doesn’t accurately account for differences in body structures within ethnic and racial groups. For example, among the Asian population, trends tend to show more serious weight-related negative health consequences at a lower BMI than among people who identify as White.

The current number of people with overweight and obesity shows that not enough is being done at a population level to help people’s health, the researchers say.

“Our analysis lays bare the decades-long failure to tackle the growing overweight and obesity epidemic in the US,” said study co-author Emmanuela Gakidou, the co-founder of the Institute for Health Metrics and Evaluation.

Demand for medications to treat obesity will grow, but Ng warns that these are “not a silver bullet.” Access to the drugs is limited, and costs can be prohibitive.

Prevention will be key, Ng said, starting with pregnancy and infant feeding practices. Healthier school meals, more regulations on junk food and programs that make fruits and vegetables more widely available will be important, the study suggests. It will also be important to create safer and more walkable neighborhoods to encourage more exercise.

There is proof that population-level solutions can work if there is a will to implement them, said Dr. Barry Popkin, the W.R. Kenan Jr. Distinguished Professor in the Department of Nutrition at the University of North Carolina.

Sweetened beverages are often a contributor to obesity, noted Popkin, who wasn’t involved with the new research. More than 40 countries and some US cities, including Philadelphia and Oakland, have imposed taxes on these drinks, and many saw a reduction in calorie consumption.

In Mexico, even in the first year of a peso-per-liter excise tax on sugar-sweetened beverages, there was a 6% reduction in the number of these beverages purchased, one of his studies showed, and 4% further reduction in the following year. People drank more water, so the number of calories they consumed was reduced, according to his research.

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Within the first three years of new food labels in Chile, he said, there was 22% less sodium consumption, 33% less sugar consumption and 22% less calorie consumption.

The challenge, Popkin said, will be finding leaders in the US who are willing to work on solutions for the obesity epidemic. He doesn’t expect it to become a priority for the second Trump administration, if the first is any indication.

In his first term, Trump’s budgets repeatedly proposed cutting hundreds of billions of dollars from the Supplemental Nutrition and Assistance Program. Trump’s administration also rolled back many of the Obama-era rules that were meant to give children access to healthier school meals and brought back sugar-sweetened beverages like chocolate milk.

“Population solutions can be very effective,” Popkin said. “And clearly we need them, based on what’s coming.”