In my latest book, The Mind Gut Immune Connection, I have discussed in detail the unfolding chronic non-contagious disease epidemic in the US, with increasing rates of obesity, type II diabetes, metabolic syndrome and several diseases affecting different organs, from the liver to the brain, and from the large intestine to the heart. We have also addressed this issue in previous posts of this blog. Sadly, the problem hasn’t gone away, and a recent study published in the prestigious journal Lancet puts the topic front and center of the health and wellness discussion.
The Lancet study focuses on the obesity epidemic in the United States, examining trends in overweight and obesity rates from 1990 to 2021, and projecting these figures up to 2050. The findings highlight the relentless upward trend in obesity rates across various age groups and states, with a substantial increase in obesity prevalence predicted if current trends persist.
The key findings of the study can be summarized as follows:
Growing Obesity Rates:
As of 2021, 15.1 million children (5–14 years), 21.4 million adolescents (15–24 years), and 172 million adults in the U.S. are overweight or obese. This amounts to a 75% rate of overweight and obesity in the adult US population. Forecasts suggest these numbers will further rise, with obesity affecting one-third of adolescents and two-thirds of adults by 2050.
Regional Variations:
Obesity rates are not uniform across states. Southern states like Mississippi and Alabama show particularly high rates. Among adolescents, Texas, Mississippi and Alabama have the highest overweight and obesity prevalence.
Sex and Gender Differences:
More females than males in the adolescent and adult groups are affected by obesity. The age-standardized prevalence for adults in 2021 was around 75.9% for males and 72.6% for females.
Economic Impact:
The economic impact of the obesity epidemic is staggering with healthcare costs related to obesity estimated to be hundreds of billions of dollars annually, and rising.
Future Projections:
By 2050, an estimated 213 million adults and over 43 million children and adolescents could be overweight or obese if preventive measures are not improved.
In my book, The Mind Gut Immune Connection, and in this blog, we have often discussed the multifactorial biological, social, psychological and structural factors underlying the obesity epidemic which are also identified by the authors, which include:
Recommendations:
To curb the obesity epidemic, the authors advocate for a “multifaceted approach” including:
The study concludes that without significant changes in national health policies and preventive measures, the U.S. obesity epidemic will continue to grow, leading to severe health and massive economic repercussions.
Why is this study important?
As also described in my book, obesity is just the most visible tip of the iceberg of the current chronic disease epidemic. Mediated by the underlying low grade immune activation originating in the gut-associated immune system, obesity and metabolic syndrome are the major risk factors for a variety of interrelated chronic diseases including metabolic, cardiovascular, neurodevelopmental and neurodegenerative diseases all of which have been increasing in prevalence during the same time period as the obesity epidemic.
As a society, are we willing to invest trillions of dollars in taking care of affected individuals and keeping mortality in check with medications and other medical interventions, or is it time to implement the obvious and much cheaper preventive intervention to stop the epidemic?

Emeran Mayer, MD is a Distinguished Research Professor in the Departments of Medicine, Physiology and Psychiatry at the David Geffen School of Medicine at UCLA, the Executive Director of the G. Oppenheimer Center for Neurobiology of Stress and Resilience and the Founding Director of the Goodman-Luskin Microbiome Center at UCLA.