We propose to conduct a cross-sectional study of 60 participants who are 18-30 years of age to undergo research PET/CT. The purpose of this study is to investigate the relationships between Brown Adipose Tissue (BAT), the adiponectin/leptin (A/L) ratio, and components of the metabolic syndrome in young adults. This study is part of a larger study aimed at understanding the mechanism of brown adipose tissue as a potential protective factor against metabolic dysfunction.