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Updated: Aug 11, 2026

Using a Combination of Indirect Calorimetry, Infrared Thermography, and Blood Glucose Levels to Measure Brown Adipose Tissue Thermogenesis in Humans
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Association between fasting substrate utilization and adipose tissue distribution

Andrea Foppiani1, Federica Sileo1, Francesca Menichetti2

  • 1Department of Food, Environmental and Nutritional Sciences (DeFENS), International Center for the Assessment of Nutritional Status and the Development of Dietary Intervention Strategies (ICANS-DIS), University of Milan, Milan, 20133, Italy; Department of Endocrine and Metabolic Diseases, IRCCS Auxologico, Clinical Nutrition Unit, Milan, 20145, Italy.

Nutrition, Metabolism, and Cardiovascular Diseases : NMCD
|August 4, 2026
PubMed
Summary

Higher fasting glucose oxidation, indicated by respiratory exchange ratio (RER), is linked to more visceral fat and less subcutaneous fat in normal-weight individuals. This suggests RER may predict metabolic risk before obesity develops.

Keywords:
Body mass indexMetabolic flexibilityRespiratory exchange ratioSubcutaneous adipose tissueSubstrate utilizationVisceral adipose tissue

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