Cold‐Activated Brown Adipose Tissue is Associated with Less Cardiometabolic Dysfunction in Young Adults with Obesity

Objective This study aimed to test the hypothesis that young adults with obesity and cold‐activated brown adipose tissue (BAT) are less likely to have metabolic dysfunction (dyslipidemia, insulin resistance, and hypertension) than those without cold‐activated BAT. Previous studies have noted a potentially protective effect of BAT and higher adiponectin/leptin ratios, but they have acknowledged that the clinical implications of these findings remain uncertain. Methods Twenty‐one females and twenty‐three males with obesity (BMI ≥ 30 kg/m 2 ) underwent a 2‐hour cooling protocol before 18 F‐fluorodeoxyglucose ( 18 F‐FDG)‐positron emission tomography/x‐ray computed tomography scan to determine the prevalence, volume, and 18 F‐FDG uptake of cold‐activated BAT. Results Cold‐activated BAT was identified in 43% of participants (11 female, 8 male); females had greater 18 F‐FDG uptake. Those with cold‐activated BAT had a lesser degree of metabolic dysfunction. Cold‐activated BAT volume correlated with triglycerides (inversely) and adiponectin (concordantly). Body‐mass‐adjusted cold‐activated BAT activity correlated with high‐density lipoprotein cholesterol (concordantly). Males with cold‐activated BAT had lower leptin and higher adiponectin/leptin ratio. Conclusions A high prevalence of cold‐activated BAT was found in the study participants. BAT could be important in decreasing metabolic dysfunction among young adults with obesity, making it a potential target for treating metabolically unhealthy obesity.