Absence of a sexual dimorphism in postprandial glucose metabolism after administration of a balanced mixed meal in healthy young volunteers

Background/Objectives: Sex-related differences in glucose homeostasis may contribute to differing diabetes prevalence by sex, but evidence is mixed due to heterogeneous protocols and inadequate control of confounders (age, body composition, physical activity). This study compared postprandial glucose metabolism between young men and women after a balanced mixed meal normalized to individual daily energy expenditure. Subjects/Methods: Thirty-six healthy young adults (18 men, 18 women; age 23.9 ± 2.8 years; BMI 21.9 ± 1.7 kg/m²) consumed, after an overnight fast, a mixed meal providing 40% of daily energy expenditure (60% carbohydrate, 25% fat, 15% protein), with energy needs estimated by Harris-Benedict resting energy expenditure multiplied by physical activity level. Blood was sampled at 0, 10, 20, 30, 45, 60, 90, 120, and 180 min for serum glucose, insulin, and C-peptide. Results: Fasting glucose was lower in women than men, while fasting insulin and C-peptide did not differ. Linear mixed models showed no significant effects of sex or sex × time interaction on postprandial glucose, insulin, or C-peptide; only time was significant. Areas under the curve did not differ by sex, indicating similar glycemic, insulinemic, and C-peptide responses. Conclusions: In healthy young adults ingesting a balanced mixed meal normalized to individual daily energy expenditure, there was no evidence of sexual dimorphism in postprandial carbohydrate metabolism.