Limitations and strengths
comorbidity
DISEASE
The cross-sectional design of this study precluded us from establishing cause-effect relationships. Our study population includes young adults without relevant disease or comorbidity; thus, our results cannot be extrapolated to older or unhealthier populations. Importantly, SCFAs were not measured and could be of interest for future studies. Further, although BAT takes up glucose from circulation, intracellular fatty acids are the main substrate of brown adipocytes in humans [