High Intake of Dietary Fiber Beneficial For Hypertension and
Higher dietary fiber intakes are associated with a reduced risk of developing cardiovascular disease (CVD), and increasing intake has been shown to reduce blood pressure and other cardiometabolic risk factors. Ovid MEDLINE, Embase, PubMed, and CENTRAL were searched to June 2021. Prospective observational studies reporting on fiber intakes and mortality in those with pre-existing CVD and controlled trials of increasing fiber intakes on cardiometabolic risk factors in those with CVD or hypertension were eligible. Outcomes were mortality (studies) and cardiometabolic risk factors (trials). Data synthesis was with random effects and dose response. Certainty of evidence was assessed using GRADE.

Three prospective studies including 7469 adults with CVD, and 12 trials of 878 adults with CVD or hypertension were identified. Moderate certainty evidence indicates reduced all-cause mortality (relative risk, RR0.75 (95% confidence interval, CI 0.58–0.97)) when comparing higher with lower fiber intakes. Low certainty evidence from trials of adults with cardiovascular disease indicates increasing fiber intakes reduced total (mean difference, MD 0.42 mmol/L (95%CI 0.78 to 0.05) and low-density lipoprotein (LDL) cholesterol (MD 0.47mmol/L (95%CI 0.85 to 0.10)). High certainty evidence from trials of adults with hypertension indicates increasing fiber intakes reduces systolic (MD 4.3 mmHg (95% CI 2.2 to 5.8)) and diastolic blood pressure (MD 3.1 mmHg (95% CI 1.7 to 4.4)). Moderate and low certainty evidence indicated improvements in fasting blood glucose (MD 0.48 mmol/L (0.91 to 0.05)) and LDL cholesterol (MD 0.29 mmol/L (95% CI 0.17 to 0.40)). Benefits were observed irrespective of cardioprotective drug use. These findings emphasise the likely benefits of promoting greater dietary fiber intakes for patients with CVD and hypertension.

Source: https://bmcmedicine.biomedcentral.com/articles/10.1186/s12916-022-02328-x