Association between frequency of spicy food consumption and hypertension: a cross-sectional study in Zhejiang Province, China

Background Hypertension is a known risk factor for multiple chronic diseases. Existing literature on the association between frequency of spicy food consumption and hypertension shows mixed findings. Methods The analyses are based on the Tongxiang baseline dataset of the China Kadoorie Biobank prospective study, including data from electronic questionnaires, physical measurements and blood sample collection. A total of 53,916 participants aged 30-79 years were included in the final analysis. Multivariable logistic regression was used to estimate the association of spicy food consumption with hypertension, and multiple linear regression was performed to explore the association of spicy food consumption with systolic and diastolic blood pressure. Results Of the 53,916 participants, 23,921 had prevalent hypertension. 12.3% of participants reported consuming spicy food weekly. Among female participants, after adjusting for socio-demographic status, lifestyle factors, BMI, waist circumference, sleep duration and snoring, when compared with females who never consumed spicy food, the odds ratios (95% CI) for hypertension were 1.02 (0.96-1.08), 0.90 (0.79-1.01), and 0.88 (0.78-0.99), respectively, for females who consumed spicy food less than once weekly, 1-2 times weekly, and >= 3 times weekly (P-trend = 0.04). The corresponding odds ratios for males were 1.02 (0.95-1.09), 1.07 (0.95-1.20), and 0.91 (0.81-1.01), respectively (P-trend = 0.39). Among current alcohol drinkers, compared to participants who never consumed spicy food, the odds ratio (95% CI) for hypertension among participants consuming spicy food daily was 0.98 (0.80-1.20). The corresponding figure for non-current drinkers was 0.72 (0.62-0.84). The association was stronger among non-current alcohol drinkers than among current drinkers (P-heterogeneity = 0.02). Conclusions Frequency of spicy food consumption is inversely associated with hypertension in females, but not in males.