Raw garlic consumption is inversely associated with prehypertension in a large-scale adult population

Previous studies have shown that allicin can lower blood pressure (BP) by reducing oxidative stress and inflammation. However, the association between habitual raw garlic intake (as allicin source) and prehypertension are unclear. The aim of this study was to investigate how raw garlic consumption is associated with prehypertension in an adult population. A cross-sectional study was conducted with 22,812 adults (mean [standard deviation] age: 39.4 [10.7] years; males, 47.7%) in Tianjin, China. Raw garlic consumption was assessed using a validated food frequency questionnaire. BP was measured at least twice by trained nurses using an automatic device. Prehypertension was defined as systolic BP of 120-139 mmHg and/or diastolic BP of 80-89 mmHg without taking antihypertensive medication. Multiple logistic regression models were used to assess the association between raw garlic consumption and prehypertension. The prevalence of prehypertension was 49.9%. After fully adjusting for potential confounders, the ORs (95% confidence intervals) of having prehypertension by increasing frequency of raw garlic consumption were 1.00 (reference) for ≤3 times/week, 0.96 (0.87, 1.06) for 4 times/week to 1 time/day, and 0.69 (0.52, 0.90) for ≥2 times/day (p for trend = 0.06). In contrast, no associations were observed between other kinds of allium vegetables consumption and prehypertension. In conclusion, our results suggested that a more frequent consumption of raw garlic was inversely associated with prehypertension. This is the first large-scale study on the association between raw garlic consumption and prehypertension in the general population.