Short-chain fatty acids are associated with adiposity and energy and glucose homeostasis among different metabolic phenotypes in the Nutritionists’ Health Study

Purpose: The gut microbiome is associated with obesity, mainly mediated by bacteria-produced short-chain fatty acids (SCFAs). It is unknown how SCFA concentrations are associated among the phenotypes metabolically healthy normal weight (MHNW), metabolically unhealthy normal weight (MUNW), metabolically healthy obese/overweight (MHO), and metabolically unhealthy obese/overweight (MUO). We compared plasma and fecal SCFA concentrations among adult women categorized according to the metabolic phenotypes mentioned above and examined associations between SCFA and adiposity and components of energy and glucose homeostasis. Methods: This was a cross-sectional study involving 111 participants. Body composition was assessed by DEXA. Energy and glycemic homeostasis were assessed by the standard mixed-meal tolerance test coupled with indirect calorimetry. SCFAs were quantified by gas chromatography and mass spectrometry. Results: Only plasma propionate was increased in the MHNW phenotype compared to the MHO and MUO phenotypes [p