Objective: To compare components of glycemic and energy homeostasis in women with metabolically healthy normal weight (MHNW) and metabolically unhealthy (MUNW), metabolically unhealthy overweight/obese (MUO) and metabolically healthy (MHO) phenotypes.

Methodology: Cross-sectional study with 104 women (18-45 years): 30 MHNW, 17 MUNW, 27 MHO, 30 MUO. Overweight was considered BMI ≥ 25 kg/m² and metabolic health without of changes in blood pressure, glycemic, lipemic levels and cardiovascular disease. The standard mixed meal tolerance test and indirect calorimetry were performed (assessments at -15, 0, 30, 60, 120 and 180 min). The quantifications were: areas under the curve (AUC) for glucose, insulin, C peptide, glucagon and GLP-1; insulin sensitivity (IS) by oral glucose insulin sensitivity index; energy expenditure, respiratory quotient, and carbohydrate and lipid oxidation rate were measured at rest and after oral stimulation.

Results: The groups did not differ regarding age and HbA1c levels. IS was decreased in MUO compared to MHNW and MHO (p<0.001). Insulin AUC was lower in MUO compared to MHNW (p=0.02), and C-peptide AUC was increased in MHO and MUO compared to MHNW (p<0.001). Resting energy expenditure was increased in overweight individuals compared to lean individuals (p <0.01). The lipid oxidation rate at time 30 min. was lower in MHNW and MUNW compared to MUO (p <0.01).

Conclusion: In young and normoglycemic women, there was lower IS and insulin secretion for the MUO phenotype. The greater rate of lipid oxidation in this group compared to the lean ones may be a reflection of the lower IS, and the inability to switch the use of energy substrate to the higher carbohydrate availability after oral stimulation. BMI is not an ideal indicator of the presence or absence of metabolic health. However, even in MHO individuals’, physiological adaptations may happen to maintain the metabolic parameters within normal range.

Disclosure

F.B. Ribeiro: None. I. Solar: None. R.G. Freitas: None. A.S. Hanada: None. M.G. Barbosa: None. C.M. Xavier: None. N.S.K. Crouchan: None. V.F.D. Santos: None. B.G. Neto: None. I.T. Silva: None. L.G.D. Folchetti: None. B. Almeida Pititto: None. S.G. Ferreira-Vivolo: None. A.J. Vasques: None.

Funding

Fundação de Apoio a Pesquisa do Estado de São Paulo (2017/10185-9)

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