Association between supraclavicular brown adipose tissue composition at birth and adiposity gain from birth to 6 months age

BACKGROUND: Brown Adipose Tissue (BAT) is associated with higher energy expenditure and lower adiposity in adults. However, the relationship between BAT composition and adiposity in early life is unknown. The objective of this study was to test the hypothesis that brown fat composition at birth is prospectively associated with adiposity gain during the first six months of postnatal life. METHODS: N=35 healthy infants were followed prospectively from intrauterine life and birth through 6 months age. Dixon MRI scans were conducted during the neonatal period to characterize supraclavicular BAT composition. Dual-energy X-ray absorptiometry to assess total body composition was performed within the first month of life and at 6 months age. RESULTS: After adjusting for potential confounding factors, a more brown-like composition (smaller fat fraction) of the supraclavicular BAT depot was associated with a smaller increase in percent body fat over the first six months of postnatal life. CONCLUSIONS: A more brown-like BAT composition at birth appears to be protective against excess adiposity gain in early life. Newborn BAT tissue may constitute a target for prevention strategies against the subsequent development of obesity.