Ethnicity Has an Impact on Body Image, BMI

Most scales used to assess body image have been created for and validated solely on Caucasian women. According to the results of two recent studies, ethnicity affects body image and body mass index (BMI).

A study of young adults

When young African-American and white adults in Birmingham, AL, Minneapolis, Chicago, and Oakland, CA, were asked specific body-image questions, some intriguing patterns based on ethnicity and gender emerged (Int J Eat Disord 25:71, 1999).

Overall, African-American and white women were more dissatisfied with their appearance and their body size/weight than were African-American and and white men. Women in both ethnic groups had similar degrees of body weight/size dissatisfaction. Although whites were more dissatisfied with their appearance, blacks scored higher on the Appearance Orientation measure, suggesting they were more invested in physical appearance than whites. Women of both ethnic groups were more invested in appearance than were men of the same ethnicity

The 1837 men (45% African-American) and 1895 women (51% African-American) were participants in the CARDIA study, a prospective epidemiologic study of the evolution of cardiovascular risk factors.

Resetting BMI cutoff levels

A team of researchers in the Netherlands found that the relationship between percent body fat and BMI differs among certain ethnic groups (Int J Obes Relat Metab Disord 22:1164, 1998). Their findings could have public health implications and could affect individual dietary programs and definitions of obesity.

Using a meta-analysis of the literature, Dr. P. Deurenberg and coworkers examined the relationship between percent body fat and BMI among different ethnic groups, including African-Americans, European and American Caucasians, Chinese, Ethiopians, Indonesians, Polynesians, and Thais. By evaluating mean values of BMI, percent body fat, gender and age from original papers they were able to evaluate the validity of BMI cut-off points for obesity among different ethnic groups.

The relationship between percent body fat and BMI differed in the ethnic groups studied. For example, given the same level of body fat, age and gender, African-American s have a 1.3 kg/m2 and Polynesians a 4.5 kg/m2 lower BMI compared to Caucasians. However, among Chinese, Ethiopians, Indonesians and Thais, BMIs are 1.9, 4.6, 3.2 and 2.9 kg/m2 lower, respectively, than BMIs in Caucasians. Slight differences in the relationship between percent body fat and BMI of American Caucasians and European Caucasians were also found.

According to the authors, differences in the body fat/BMI relationship in different ethnic groups could be due to differences in energy storage as well as to variations in body build. They recommend that an individual’s ethnic group be taken into consideration when BMI cutoff levels are set. These findings may also have important clinical implications at the lower end of charts, where diagnoses of anorexia nervosa are made. The results suggest that diagnoses made strictly on the basis of BMI cutoff points may be clinically insensitive in individuals.