The prevalence of unhealthy weight, both over and underweight, can differ between children of different ethnicities.
The National Child Measurement Programme (NCMP) data 2019/20 showed the prevalence of under and overweight in children of reception age. The highest prevalence of overweight and obesity at reception age is found in black and black British children (28.5%) and the lowest is found in Chinese children (14.9%). In terms of underweight, the highest levels are found in Asian and Asian British children (3.5%) and the lowest in white children (0.5%).
There are some points to take into account when considering ethnic differences in obesity. Obesity is measured by Body Mass Index (BMI) (see Assessing Weight in Young Children module for a further explanation), which is a measure of weight for height. It has been shown that people of Asian origin accumulate a higher level of body fat at the same BMI as white people, which means that the BMI cut-offs for underweight and overweight might be misleading for these populations. Furthermore, adults of Asian origin (particularly South Asian) are at higher risk of cardiovascular disease than white populations of the same BMI. Therefore, some experts have suggested the BMI cut-off for obesity should be lower for Asian populations.