Study Links Life-Course Clinical Obesity to Signs of Brain Health Changes in Midlife

October 8, 2026 · Baton Rouge, LA

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Bogalusa Heart Study findings provide new evidence connecting cumulative clinical obesity with white matter changes in the brain

New research from the Bogalusa Heart Study has found that greater exposure to clinical obesity during young adulthood is associated with a greater burden of white matter changes in the brain by midlife, providing new insight into how metabolic health across the lifespan may influence brain health.

The study, “Life-Course Clinical Obesity and Midlife White Matter Hyperintensity Burden: The Bogalusa Heart Study,” published in Neurology Open Access, used the clinical obesity framework developed by the Lancet Commission on the Definition and Diagnosis of Clinical Obesity to examine the relationship between obesity and brain health. LSU’s Pennington Biomedical Research Center’s Dr. Owen Carmichael is part of the Bogalusa Heart Study research team.

Researchers analyzed data from 190 participants in the Bogalusa Heart Study, a landmark longitudinal study that has followed participants from childhood into adulthood for more than 50 years. Participants underwent repeated assessments of their cardiometabolic health during young adulthood and midlife and later received brain MRI scans.

Rather than relying solely on body mass index (BMI), researchers classified participants according to the Lancet Commission framework, which distinguishes between preclinical obesity, characterized by excess adiposity without evidence of ongoing obesity-related illness, and clinical obesity, in which excess adiposity is accompanied by impairment of organ or tissue function or limitations in daily activities. The Commission, which included three Pennington Biomedical researchers, developed the definition to provide a more clinically meaningful approach to identifying obesity-related illness than BMI alone.

Researchers found that participants with greater cumulative exposure to clinical obesity from young adulthood into midlife had greater amounts of white matter hyperintensities (WMH) when they reached their mid-50s. WMH are areas of increased signal on brain MRI that can reflect small-vessel disease and other forms of injury. Researchers did not find a significant association between cumulative clinical obesity and the ratio of gray matter volume to total intracranial volume.

“People have been studying the relationship between obesity and brain aging for a long time, and those studies have been really confusing, with some studies even suggesting that having more obesity might be better for the brain,” said Dr. Carmichael, James W. and Neil Ann Parks Professor for Dementia Research, Prevention and Treatment. “One reason for the confusion is that we never did a good job of separating out, among persons with excess body fat, those who did vs. didn’t have serious metabolic health consequences associated with it. The Lancet Commission definition of clinical obesity tries to get us beyond that. We found that people who had more exposure to clinical obesity over decades had worse brain health in midlife; something you can really only discover in a long-term study like the Bogalusa Heart Study."

These findings build on the work of the Lancet Commission, which introduced a framework for distinguishing clinical obesity from preclinical obesity. Pennington Biomedical researchers Dr. Eric Ravussin, Dr. Philip Schauer and Dr. John Kirwan served on the international commission, which included experts from multiple medical specialties and countries.

“The Lancet Commission sought to move the definition of obesity beyond BMI and toward a better understanding of how excess adiposity affects the health and function of the body’s tissues and organs,” said Dr. Ravussin, LSU Boyd Professor and Douglas L. Gordon Chair in Diabetes and Metabolism. “This study is an important example of how that framework can be applied to longitudinal research. By considering the metabolic consequences of excess adiposity over time, researchers can begin to better understand how clinical obesity may contribute to health outcomes later in life, including brain health.”

The study's findings are particularly notable because most previous research examining obesity and brain health has relied on BMI measurements at a single point in time.

Among the paper’s authors are Christian Corsten and Mitch Epps, LSU undergraduate students working on Dr. Carmichael’s research team at the time of the study.

“I think this study suggested several important things: metabolic health is not just a snapshot in time, and looking beyond BMI alone may provide a more clinically meaningful picture of obesity-related health,” Corsten said. “The effects of metabolic disease can accumulate across the lifespan, and that cumulative burden may have meaningful consequences for how the brain ages. I was very fortunate to have the opportunity to work with the Bogalusa Heart Study dataset, which is uniquely suited to answering these kinds of life-course questions because of the decades of longitudinal data it contains.”

Epps said, “I’m grateful for the opportunity to conduct research like this as an undergraduate, and for having the Bogalusa Heart Study data available to explore our own questions.”

The Bogalusa Heart Study began in 1972 and has followed participants from childhood into adulthood, collecting detailed information on cardiovascular and metabolic health across the lifespan. The Bogalusa Heart Study's longitudinal design allowed researchers to examine cumulative exposure to clinical obesity across adulthood.