BACKGROUND: Ethnic differences in the association between body mass index (BMI) and body fat suggest that body composition varies across ethnic groups. OBJECTIVE: To investigate the association between impedance index - a measure of tissue resistivity - and BMI in adults of different ethnic groups (Asian Indians, West Africans and White Caucasians) living in their native countries. METHODS: Male (n=329) and female (n=277) adult subjects (18-50 years) living in urban areas in the UK, The Gambia and Pakistan were studied. Body weight and height were measured and BMI calculated. The same leg-to-leg bioimpedance instrument was used in each study and impedance index (height(2) (cm)/impedance (Omega)) used as measure of tissue resistivity. RESULTS: In women, Asian Indians and West Africans had a significantly greater increase in impedance index per unit increase in BMI compared with white Caucasians (P<0.001). In men, Asian Indians had a significantly lower impedance index compared with West Africans and white Caucasians (P<0.001). CONCLUSION: Different ethnic groups may have different tissue resistivity for the same BMI indicative of systematic differences in body composition.

Original publication

DOI

10.1038/sj.ejcn.1602678

Type

Journal article

Journal

Eur J Clin Nutr

Publication Date

11/2007

Volume

61

Pages

1337 - 1340

Keywords

Adolescent, Adult, African Continental Ancestry Group, Asian Continental Ancestry Group, Body Composition, Body Height, Body Mass Index, Body Weight, Electric Impedance, Ethnic Groups, European Continental Ancestry Group, Extremities, Female, Humans, Male, Middle Aged, Reproducibility of Results, Sensitivity and Specificity