Association between Dietary Acid Load and Blood Pressure: A Systematic Review and Meta-analysis

Background: Existing data on the association between dietary acid load and blood pressure are not conclusive. This systematic review and meta-analysis aimed to combine findings of evidence regarding the association between dietary acid load and blood pressure. Methods: MEDLINE and EMBASE databases were searched for studies published up to November 2016. Effect sizes of eligible studies were pooled using random-effects models. Heterogeneity was tested using Cochrane’s Q test. Subgroup analyses were done according to the method used for estimating dietary acid load. Results: Of 7033 records, 8 articles (7 cross-sectional, 1 longitudinal) were eligible for inclusion. Higher dietary acid load was associated with high systolic blood pressure (SBP) (mean difference [MD] = 0.84 mm Hg; 95% CI, 0.04 to 1.64; I2 = 98.4%; p= 039) and diastolic blood pressure (DBO) (MD = 0.75 mm Hg; 95% CI, 0.27 to 1.24; I2 = 75.1%; p=002). Subgroup analyses showed that the type of populations involved and participant sex were sources of heterogeneity for both SBP and DBP, while baseline blood pressure and age were heterogeneity sources exclusively for DBP. Conclusion: High dietary acid load is associated with greater blood pressure. Further studies are needed to explore the precise impact of low dietary acid load on blood pressure in patients with hypertension