Exploring the effect of ethnicity on diet induced thermogenesis

Asians have a higher body fat to fat free mass percentage and greater visceral adiposity for the same age, gender and BMI compared with Caucasian populations, with this difference already evident at a young age. This unfavourable composition profile has been associated with greater risk of developing type 2 diabetes, insulin resistance and cardiovascular disease. Ethnic susceptibility towards disturbed energy homeostasis may be a factor contributing to these disparities. Total energy expenditure comprises resting metabolic rate (RMR) (~60-70%), physical activity (~20%) and diet induced thermogenesis (~10%). Asians have lower RMR which can be explained by lower fat free mass given fat free mass is the main determinant (60-70%) of RMR. A 3 year follow up study showed that a low RMR even after adjusting for fat, fat free mass, age and gender were associated with an increased risk of weight gain. There is evidence that diet induced thermogenesis may be influenced by meal size and composition, obesity, age and physical activity, however there has been no research looking at the impact of ethnicity. Although diet induced thermogenesis contributes a smaller component of total energy expenditure, any deficits may contribute to impairments in energy balance and cumulative weight gain over time.