Obese young men had less activated brown adipose tissue than lean men (mean, 130 vs. 334 mL) but more fat in BAT-containing depots (mean, 1,646 vs. 855 mL).
Cross-Sectional
Does the amount and distribution of activated brown adipose tissue differ between lean and obese young men?
Active brown adipose tissue is present in specific depots in adult humans and is less abundant in obese compared to lean young men, highlighting its thermogenic potential.
Absolute Event Rate: 130% vs 334%
F-labeled fluorodeoxyglucose positron emission tomography/computerized tomography (PET/CT). Obese men had less activated BAT than lean men (mean, 130 vs. 334 mL) but more fat in BAT-containing depots (mean, 1,646 vs. 855 mL) with a wide range (0.1-71%) in the ratio of activated BAT to inactive fat between individuals. Six anatomic regions had activated BAT-cervical, supraclavicular, axillary, mediastinal, paraspinal, and abdominal-with 67 ± 20% of all activated BAT concentrated in a continuous fascial layer comprising the first three depots in the upper torso. These nonsubcutaneous fat depots amounted to 1.5% of total body mass (4.3% of total fat mass), and up to 90% of each depot could be activated BAT. The amount and activity of BAT was significantly influenced by region of interest selection methods, PET threshold criteria, and PET resolutions. The present study suggests that active BAT can be found in specific adipose depots in adult humans, but less than one-half of the fat in these depots is stimulated by acute cold exposure, demonstrating a previously underappreciated thermogenic potential.
Leitner et al. (Mon,) conducted a cross-sectional in Obesity. Obesity vs. Lean was evaluated on Activated brown adipose tissue (BAT) volume. Obese young men had less activated brown adipose tissue than lean men (mean, 130 vs. 334 mL) but more fat in BAT-containing depots (mean, 1,646 vs. 855 mL).