A large retrospective study published in Nature on October 14, 2026, reveals that active brown fat is linked to lower rates of type 2 diabetes, heart disease, anxiety, and depression. Researchers discovered that the blood pressure drug losartan stimulates this thermogenic tissue in mice and cells, opening new doors for drug repurposing.
Scientists have long viewed brown adipose tissue primarily as a metabolic furnace that burns calories to generate heat. Until a landmark study proved adults retain it in late 2009, researchers believed the tissue vanished after infancy. Now, a massive retrospective analysis published in the journal Nature has expanded our view of what this specialized tissue does for the human body.
AI Analysis of 100,000 Patient Scans Links Brown Fat to Lower Disease Rates
Led by Paul Cohen at Rockefeller University, working alongside Heiko Schöder and Daniel Lafontaine at Memorial Sloan Kettering Cancer Center, researchers evaluated PET/CT scans and medical records from 101,243 patients treated at Memorial Sloan Kettering Cancer Center between June 2009 and July 2024. The analysis doubled the cohort size of a similar 2021 study that initially tied brown fat to lower odds of cardiometabolic conditions like coronary artery disease and type 2 diabetes.
Patients with detectable brown adipose tissue showed lower prevalence across a broad spectrum of conditions when artificial intelligence and machine learning tools semi-automatically quantified brown fat activity across more than 500 diagnostic codes. Initial screening revealed 58% lower odds of type 2 diabetes, 47% lower odds of chronic ischaemic heart disease, and lower odds of primary hypertension among individuals with active brown fat.
We only looked for a few diagnostic codes before, mainly focusing on cardiovascular disease since that’s what this tissue has historically been associated with. The scope of this new analysis is far more expansive. We doubled our number of patients and considered more than 500 codes, which allowed us to unearth many new insights.
Dr Paul Cohen, researcher at Rockefeller University
Mental Health Links Emerge From Patient Data
Patients with greater brown fat presence demonstrated a lower incidence of depressive episodes and anxiety disorders when unbiased screening across 511 ICD codes went beyond traditional cardiometabolic outcomes. Experts describe the work as one of the most comprehensive and, probably, significant works in the field,
according to Dr. Shingo Kajimura, a molecular biologist at Harvard Medical School.
First author Nicolás Gómez-Banoy, an endocrinologist and instructor of clinical investigation at Rockefeller and Weill Cornell Medicine, pointed to metabolic health as a plausible driver for the observed mental health patterns.
A potential explanation is that, because people with brown fat have a healthier metabolic profile, they will have less psychiatric issues.
Dr Nicolás Gómez-Banoy, physician-scientist at The Rockefeller University
Researchers found that activity within the axillary, or armpit, depot showed the strongest association with favorable cardiometabolic outcomes and healthier white fat distribution, including lower amounts of visceral fat.
Testing Losartan as a Potential Brown Fat Activator in Cells and Mice
Patients taking angiotensin receptor blockers, a class of blood pressure medications, exhibited a higher presence of brown fat in their scans because clinical records included outpatient medications.
The team examined the impact of the ARB medication losartan to test this relationship experimentally. Losartan directly increased metabolic activity in cultured brown fat cells by inducing uncoupling protein 1, the primary mitochondrial protein that drives thermogenesis. Healthy mice treated with losartan demonstrated enhanced metabolic markers, including increased energy expenditure, oxygen consumption, and carbon dioxide production, while maintaining a steady body weight.
Dr Nicolás Gómez-Banoy said the molecular interactions by which losartan induced these effects were distinct from the mechanisms underpinning its blood pressure–lowering properties. Researchers emphasize that the human data remains observational despite these promising cellular and animal findings. More work is needed to prove that brown fat is indeed causing all these benefits,
noted Dr. Irfan Lodhi, a molecular biologist at Washington University in St. Louis. But it's still a very interesting and surprising study.
