By Marie Ng
Nearly half of adolescents and three-quarters of adults in the U.S. were classified as being clinically overweight or obese in 2021. The rates have more than doubled compared with 1990.
Without urgent intervention, our study forecasts that more than 80% of adults and close to 60% of adolescents will be classified as overweight or obese by 2050. These are the key findings of our recent study, published in the journal The Lancet.
Synthesizing body mass index data from 132 unique sources in the U.S., including national and state-representative surveys, we examined the historical trend of obesity and the condition of being overweight from 1990 to 2021 and forecast estimates through 2050.
For people 18 and older, the condition health researchers refer to as “overweight” was defined as having a body mass index, or BMI, of 25 kilograms per square meter (kg/m²) to less than 30 kg/m² and obesity as a BMI of 30 kg/m² or higher. For those younger than 18, we based definitions on the International Obesity Task Force criteria.
This study was conducted by the Global Burden of Disease Study 2021 U.S. Obesity Forecasting Collaborator Group, which comprises over 300 experts and researchers specializing in obesity.
Why it matters
The U.S. already has one of the highest rates of obesity and people who are overweight globally. Our study estimated that in 2021, a total of 208 million people in the U.S. were medically classified as overweight or obese.
Obesity has slowed health improvements and life expectancy in the U.S. compared with other high-income nations. Previous research showed that obesity accounted for 335,000 deaths in 2021 alone and is one of the most dominant and fastest-growing risk factors for poor health and early death. Obesity increases the risk of diabetes, heart attack, stroke, cancer and mental health disorders.
The economic implications of obesity are also profound. A report by Republican members of the Joint Economic Committee of the U.S. Congress, published in 2024, predicted that obesity-related health care costs will rise to US$9.1 trillion over the next decade.
The rise in childhood and adolescent obesity is particularly concerning, with the rate of obesity more than doubling among adolescents ages 15 to 24 since 1990. Data from the National Health and Nutrition Examination Survey revealed that nearly 20% of children and adolescents in the U.S. ages 2 to 19 live with obesity.
By 2050, our forecast results suggest that 1 in 5 children and 1 in 3 adolescents will experience obesity. The increase in obesity among children and adolescents not only triggers the early onset of chronic diseases but also negatively affects mental health, social interactions and physical functioning.
What other research is being done
Our research highlighted substantial geographical disparities in overweight and obesity prevalence across states, with southern U.S. states observing some of the highest rates.
Other studies on obesity in the United States have also underscored significant socioeconomic, racial and ethnic disparities. Previous studies suggest that Black and Hispanic populations exhibit higher obesity rates compared with their white counterparts. These disparities are further exacerbated by systemic barriers, including discrimination, unequal access to education, health care and economic inequities.
Another active area of research involves identifying effective obesity interventions, including a recent study in Seattle demonstrating that taxation on sweetened beverages reduced average body mass index among children. Various community-based studies also investigated initiatives aimed at increasing access to physical activity and healthy foods, particularly in underserved areas.
Clinical research has been actively exploring new anti-obesity medications and continuously monitoring the effectiveness and safety of current medications.
Furthermore, there is a growing body of research examining technology-driven behavioral interventions, such as mobile health apps, to support weight management. However, whether many of these programs are scalable and sustainable is not yet clear. This gap hinders the broader adoption and adaptation of effective interventions, limiting their potential impact at the population level.
What’s next
Our study forecasts trends in overweight and obesity prevalence over the next three decades, from 2022 to 2050, assuming no action is taken.
With the advent of new-generation anti-obesity medications, obesity management could change substantially. However, the extent of this impact will depend on factors such as cost, accessibility, coverage, long-term efficacy and variability in individual responses. Future research will need to leverage the most up-to-date evidence.
Marie Ng is Affiliate Associate Professor of Global Health at the University of Washington.
Dennis Berg says
Follow Seattle’s lead and put a large national excise tax on sugary drinks. Take it further and tax all junk food to the point it is painful. Remove sugary drinks, junk food and highly processed meats from the Supplemental Nutrition Assistance Program (SNAP). It’s outrageous these foods are allowed on SNAP, but it shows the power factory food companies have over politicians and DC bureaucrats.
D says
When a hamburger and fries are cheaper than salads, where there is added sugar in everything, and food products are pumped full of artificial ingredients and hormones. What do you expect? It’s just about diet and exercise.
D says
It’s NOT just about diet and exercise.
Joe D says
I agree with both Dennis and “D”
As a retired Registered Nurse with a Master’s degree as a Clinical Nurse Specialist and Certified Nurse Case manager with 43 years of experience. Obesity is surely going to kill almost 1/2 of us eventually.
The reality is Sugary and High Fat foods taste really GOOD …and usually they are CHEAP and easy to grab off the shelf almost ANYWHERE! Especially available at EVERY checkout counter…even pharmacies and hospitals!
“D” is correct, if a burger and fries is cheaper than a healthy salad, guess what the choice will be?
I have to admit, over the years (especially in the last 10 years of my career, where I had mostly a desk job) I let my weight creep up to a BMI (body mass index) of 28 (maximum should be under 25)…making me “obese.” A BMI of 30+ makes a person “morbidly obese”…as in DANGEROUS to your life! People can reach a BMI of 40-50+.
I was gifted a Google “Fitbit” smart watch (monitoring heart rate/breathing/activity/exercise/ and monitoring food intake and weight loss). It (along with the supplied phone tracking app), allowed me to track my heart health, breathing /sleep quality/blood oxygen level/ diet intake, weight loss (24 lbs with 3 more to go to drop my BMI below 25)…all for $140 (or frequently on sale to $100)! It has taken 18-24 months ( a goal of 0.5-1 lb/week, with periods of backsliding and plateauing). One of the most useful features of the FIT BIT phone app is it logs the Nutritional value of what you are eating, so you know if you are calcium or potassium deficient. It can also tell you if you are vitamin deficient, based on your diet!
I agree that high sugar/fat “snack foods” should not be part of the SNAP program. My prior state of Maryland took sugared sodas and high calorie snack foods out of the school vending areas.
Obesity doesn’t stand by itself, but can lead to diabetes/ heart disease/ kidney disease/liver disease/ stroke/ arthritis and the need for joint replacement surgery due to weight stressed joints.
In reality, we are eating ourselves to death!
DaleL says
A lot of people in America do not walk. A friend of mine is a retired 747 pilot. He still has his own plane and takes day trips to small airports. We went to Perry recently. The Huggles restaurant that we walked to is a mile from the airport. The person at the control building said, “You have a car?” And something like, “…that’s too far to walk.” It wasn’t that far, just 20 minutes or so each way.
Once a person becomes obese, walking can be difficult. Once a person is obese, it then becomes even more difficult to lose weight. Still, there is a saying among runners, “You cannot outrun your mouth.” The meaning is that no matter how much a person runs, it is possible to eat enough to gain weight. Ultimately, it is calories in versus calories burned.
BMI was created as a general measure for populations. It is fair general measure for individuals. However, it does not take into account individual body shapes, age, sex, or genetic background. I’ve been “overweight” according to the BMI calculation just about my whole life. Even when I was running 5 and 10K distances a decade ago, the lowest my BMI reached was 25.1, overweight!
Enjoy your holiday treats everyone. Just remember to do it in moderation and WALK some of it off.
Life Style Change says
As someone who has been on their own weigh loss & health journey…..
The problem is the availability of unchecked fast foods, the lack of American exercise, & proper nutrition education.
What good are food labels when no one reads them? There’s zero enforcement & oversight of what food is sold. Once I started to read labels & educate myself I was shocked at how much junk, sodium, fat, & calories are in everyday foods that everyone consumes regularly. If something contains contains 71grams of added sugar like a Starbucks drink does, they should pay a fine.
I changed 2 things in my life. I started to exercise & eliminate bad food, & eat good food, I have lost 60lbs in only 5 months time!
It’s not a diet, it’s not an exercise program. It’s a lifestyle change! I’m never eating any of that junk again!
My Two Cents says
While this article and the subsequent comments focus primarily on the food industry, lifestyles, socio-economic effects, etc., one cannot ignore another factor, that while not really encouraging obesity, has nevertheless forced obesity to become more acceptable. The complaints against “fat-shaming” have given rise to a culture that gives shelter to the obese and demands that society accept obesity as a more “normal” human condition.
Social media plays a huge part here. On the one hand, you have the medical profession trying to encourage more healthful lifestyles and food consumption habits and on the other you have influencers calling out how bad it is to to reproach someone for eating unhealthy foods, dressing unbecoming for their size, or living a totally sedentary lifestyle.
In online social groups, those who try to encourage someone who bemoans the fact that they cannot find a love interest to lose weight and care more about their appearance in order to find a soul mate are often attacked as being fat-phobic. Genuine care is just not recognized. Excuses and feel-good messages play into the deception: “Oh, it’s what’s inside that counts, appearances are deceiving.”
There are even reality TV shows: “My 600-lb Life” and “1000-lb Sisters” which have made stars of these individuals.
This has all contributed to the difficulties in approaching obesity with the objectives to focus on improving one’s health and overall quality of life.
Sad situation.