Relationship between BMI with percentage body fat and obesity in Singaporean adults – The Yishun Study.
Background: The main aim of this study was to the determine relationship between Body Mass Index (BMI) and
percentage body fat (BF%) in Singaporean adults, derive a prediction model to estimate BF%, and to report
population BF%. The secondary aim was to determine the prevalence of overweight and obesity based on BF%
threshold and the new risk categories for obesity in Singaporean population.
Methods: This was a population-based study of 542 community-dwelling Singaporeans (21–90 years old, 43.1%
men). Anthropometry and body composition were assessed. Relationship between BMI and BF% were analysed
using multiple regression models. Prevalence of overweight and obesity were estimated using WHO and Singapore
Ministry of Health (MOH) Clinical Practice Guidelines for BMI classification, and BF% cut-off points of 25 and 35% for
men and women respectively.
Results: We derived a prediction model to estimate BF% based on BMI, age and sex. The current cohort of
Singaporeans when compared to Caucasians in the US and Europe as well as a Singapore cohort from 20 years age
have higher BF% when matched for BMI, age, and sex. The overall population-adjusted prevalence of obesity
according to WHO International classification (BMI ≥30 kg/m2) was 12.9% (14.9% men; 11.0% women); and 26.6%
(30.7% men; 22.8% women) according to the MOH classification (BMI ≥27.5 kg/m2). However, using the BF% cut-off
(> 25% for men and > 35% for women) resulted in very high prevalence of obesity of 82.0% (80.2% men; 83.8%
women).
Conclusion: There is a large discrepancy between BF% and BMI measured obesity in Singaporean adults. The
results confirmed that Singaporean adults have higher BF% at lower BMI compared to US and Europe white
counterparts; and that BF% in our population has increased over two decades.