There are ethnic differences recorded in glycaemic response and rates of type 2 diabetes mellitus (DM) between Chinese and Caucasian populations. Whether these differences are evident in matched healthy, lean, active, young adults is unclear. This study compares the postprandial glycaemic response of a group of Chinese participants (n = 49) with a group of similar Caucasians, (n = 48) aged 23.8 (±4.35 years), body mass index (BMI) 22.7 (±2.6) kg/m², healthy (free from non-communicable disease), and lean (body fat % 23.28% (±5.04)). Participants undertook an oral glucose tolerance test to identify any significant differences in postprandial blood glucose response. Body fat percentage, body mass, age, physical activity, baseline glucose and HbA1c did not significantly differ between groups. Data from food frequency questionnaires indicated that the Chinese participants consumed less starchy foods, candy and "other" sweets and sugary drinks, and more rice than the Caucasians (all p ≤ 0.001), but not a greater overall intake of carbohydrates or any other macronutrient (all p > 0.05). The two groups' postprandial blood glucose responses and 2-h incremental area under the curve values (iAUC)-156.67 (74.12) mmol/L 120 min for Caucasians versus 214.03 (77.49) mmol/L 120 min for Chinese-indicate significant differences (p = 0.003 and p < 0.001 respectively) between groups. Findings suggest that the difference between the two groups' iAUC values do not relate to obvious lifestyle factors. The Chinese group were eating the least sugary and starchy food but had the highest iAUC. It is argued that the Chinese group in this investigation have the most favourable BMI, body fat percentage, and body mass, yet "poorest" glycaemic response.
Keywords: diabetes; ethnicity; glycaemic response; iAUC.