Baseline characteristics did not differ between the 2 intervention groups of the study population (Table 1). Energy intake and macronutrient composition of the diet did not differ between groups at baseline and did not change in the placebo or cinnamon group during the intervention period. The recorded mean energy intake in the entire population was 76.8 ± 4.0 kJ/kg body mass, with 50.6 ± 1.0% of energy as carbohydrates, 30.6 ± 1.0% of energy as fat, and 16.8 ± 0.6% of energy as protein. Alcohol consumption was negligible during the intervention period.
Before supplementation, plasma HbA1c and fasting glucose and insulin concentrations did not differ between the groups (Table 2). During the intervention period, there were no time × treatment interactions for plasma HbA1c, fasting glucose, or insulin concentrations.