Correlation between tea consumption and prevalence of hypertension among Singaporean Chinese residents aged ⩾40 years

By a cross-sectional epidemiology study, we attempted to correlate the consumption of tea and/or health supplements, living habits and socio-demographic factors to the prevalence of hypertension among Singaporean Chinese residents. Singaporean Chinese residents aged ⩾40 years were randomly selected and interviewed face-to-face by clinical research assistants. Hypertension was defined as measured systolic blood pressure at least 140 mm Hg and/or diastolic blood pressure at least 90 mmHg or self-reported history/treatment for hypertension. The prevalence of hypertension among the whole investigated population (N=1184, 58.27% females) was 49.73% and the prevalence increased to 66.47% in the sub-population aged ⩾60 years. High risk of hypertension was associated with age ⩾60 years (odds ratio (OR): 4.15–4.19, P<0.01), obesity (body mass index >25 kg m−2, OR: 2.10–2.11, P<0.01), family history of hypertension (OR: 2.69–2.76, P<0.01), diabetes history (OR: 2.29–2.33, P<0.01), hyperlipidemia history (OR: 1.79–1.80, P<0.01), male (OR: 1.56–1.59, P<0.01) and coffee intake (OR: 1.44–1.46, P<0.05). In contrast, drinking green tea at least 150 ml per week was associated with lower hypertension risk (OR: 0.63, 95% confidence interval (CI): 0.43–0.91, P<0.05). Drinking combination of green tea and British tea was associated with higher reduction in the risk of hypertension (OR: 0.58, 95% CI: 0.39–0.85, P<0.05). This cross-sectional study suggests that consumption of tea, especially green tea and British tea, was associated with lowering the risk of hypertension. On the other hand, consumption of coffee could be a risk factor of hypertension. These findings may provide useful information for health promotion to reduce risk of hypertension and warrant further study to confirm and elucidate such association.