CONCLUSIONS OBJECTIVE The objective of the study is to explore the relationship between body mass index (BMI) and percent body fat (PBF) in relation to hypertension among adult Bengalee males of low socio-economic status living in a slum area of West Bengal, India. METHODS A cross-sectional survey was carried on 436 males aged 18-60 years in a slum area called Bidhan Colony, which is approximately 15 km from Kolkata city. Data on anthropometric measurements and blood pressure were collected, following standard techniques. Logistic regression and receiver operating characteristic (ROC) curve analysis were used for testing the relationship between BMI and PBF relative to hypertension. RESULTS About 4.25% and 50% of the normal (BMI 18.5-22.9 kg/m(2)) and overweight (BMI 23.0-24.9 kg/m(2)) subjects, respectively, were obese according to the PBF cut-off point of >25%. The ROC curve analysis indicated that the BMI cut-off ≥23 kg/m(2) was appropriate for detecting obesity relative to hypertension. It was observed that the prevalence of hypertension increased significantly with age (r = 0.226, p < 0.001). Adjusting for age, the subjects with BMI 23-24.99 kg/m(2) had about 3.2 times (95% CI: 1.61-6.27) greater risk of hypertension than those with BMI < 23 kg/m(2), and the risk for those with BMI ≥ 25 kg/m(2) was about 4.5 times (95% CI: 2.06-9.57). As for PBF, the risk of hypertension was about 2.6 times (95% CI: 1.38-4.80) for the subjects with PBF > 25% compared to those with PBF ≤ 25%. CONCLUSIONS Our study validated the BMI cut-off point proposed by the WHO for Asia-Pacific populations for screening the individuals who are likely at risk of overweight. However, such data should be substantiated by independent risks of adverse health outcomes that need for public health intervention.