Objective To explore the relationship between dietary fiber intake and hypertension in different populations.

Methods Dietary fiber intake was calculated using the data from 2015—2016 National Health and Nutrition Examination Survey (NHANES) database by combining dietary data collected by the 24-hour dietary recall method with the USDA Food and Nutritional Database. Hypertension was defined based on blood pressure values obtained through questionnaires and mobile center measurements. Logistic regression models were used to analyze the relationship between dietary fiber intake and hypertension in individuals aged ≥18 years. Generalized additive model (GAM) and smoothed curve fitting were used to analyze the dose-response relationship between them.

Results Compared with the low dietary fiber intake (＜17.75 g/d) group , in the total population, the prevalence risk of hypertension was 18% lower in the high dietary fiber intake (≥18.85 g/d) group (OR＝0.82, 95%CI 0.68-0.98). In the male population, the risk of hypertension in the high dietary fiber intake group decreased by 23% (OR＝0.77, 95%CI 0.60-0.98). In the female population, when dietary fiber intake was ＞28.05 g/d, the risk of hypertension decreased by 6% (OR＝0.94, 95%CI 0.89-0.99) for 1 g/d increase in dietary fiber intake. In the population aged ＞60 years, the risk of hypertension decreased by 31% in the high dietary fiber intake group (OR＝0.69, 95%CI 0.48-0.99). In the population aged ≤45 years, the risk of hypertension decreased by 6% (OR＝0.94, 95%CI 0.88-0.99) for 1 g/d increase when dietary fiber intake ＞34.5 g/d.

Conclusions High dietary fiber intake is associated with a decreased risk of developing hypertension, and a reasonable increase in dietary fiber intake can help reduce the incidence of hypertension.