In a remarkable shift from long-standing trends, new research reveals that US adult obesity rates decreased in 2023 for the first time in more than ten years. The study, which analyzed over 47 million body mass index measurements from more than 16 million adults, suggests this change may be linked to increased use of weight-loss medications and pandemic-related behavioral changes.
Published in JAMA Health Forum | Estimated reading time: 4 minutes
Researchers from Boston Children’s Hospital and Harvard Medical School examined nationwide trends in body mass index (BMI) and obesity rates between 2013 and 2023. Their findings show that after years of steady increases, obesity rates plateaued in 2022 and then declined slightly in 2023, marking a potential turning point in America’s obesity epidemic.
The study reveals particularly notable decreases in certain demographics and regions. The South, which had the highest rate of weight-loss medication use, showed the most significant decline. The researchers found that adults aged 66 to 75 years and women also experienced notable decreases in obesity rates.
Lead researcher Dr. Benjamin Rader from Boston Children’s Hospital’s Computational Epidemiology Lab and his colleagues analyzed data from the Optum deidentified Market Clarity Data system, which includes both medical claims and electronic health records. Their analysis showed that mean population BMI rose consistently from 2013 until 2021, reached a plateau in 2022 at 30.24, and then decreased slightly to 30.21 in 2023.
A particularly intriguing aspect of the findings involves regional differences in the use of GLP-1RA medications (like semaglutide). The South showed the highest rate at 6.0% of patients receiving these medications, compared to just 3.4% in the West. However, the researchers caution that medication dispensing rates don’t necessarily reflect actual usage patterns.
Glossary
- BMI (Body Mass Index)
- A measure calculated as weight in kilograms divided by height in meters squared, used to categorize body weight status.
- GLP-1RA
- Glucagon-like peptide 1 receptor agonist – a class of medications used for weight loss and diabetes management.
- Obesity
- A medical condition defined as having a BMI of 30 or greater.
Test Your Knowledge
When did US obesity rates first show a decline in this study?
The first decline was observed in 2023, after plateauing in 2022.
What was the average BMI measurement in 2023?
The mean population BMI in 2023 was 30.21.
Which region showed both the highest GLP-1RA medication use and the most significant decrease in obesity rates?
The South showed both the highest GLP-1RA dispensing rate (6.0%) and the most notable decrease in obesity rates.
What are the key limitations of this study that could affect interpretation of the results?
The study is limited by possible selection bias, as BMI recorded during medical visits may have skewed estimates. Additionally, medication dispensing rates don’t necessarily reflect actual usage, and the South’s results may have been influenced by disproportionately high COVID-19 mortality among individuals with obesity.
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