DIETARY ACID LOAD AND CARDIO -METABOLIC RISK FACTORS: A SYSTEMATIC REVIEW AND META-ANALYSIS OF OBSERVATIONAL STUDIES

Background and Aim: Dietary acid load (DAL) might contribute to the development of changing the normal levels of cardio-metabolic risk factors; however, the results are conflicting. This study was conducted to determine the relationship between DAL and cardio-metabolic risk factors. Methods: A systematic search was conducted in electronic databases including PubMed, EMBASE, Scopus and Google Scholar for observational studies which assessed the cardiometabolic risk factors across DAL. Outcomes were lipid profile, glycemic factors, and anthropometric indices. Effect sizes were derived using fixed or random effects model. Also, subgroup analysis was performed to find the probable source of heterogeneity. Egger test was performed for finding any publication bias.Results: Thirty-one studies were included in the current review with an overall 92478 sample size. There was a significant relationship between systolic blood pressure (WMD: 1.58 mmHg,95%CI: 0.30, 2.85; P= 0.015) (I2= 94.1%), diastolic blood pressure (WMD: 0.71 mmHg, 95%CI:0.16, 1.26; P= 0.011) (I2 = 74.6%) and DAL. Serum lipids, glycemic parameters including fasting blood sugar, hemoglobin A1C, serum insulin and HOMA-IR and anthropometric measures including body mass index and waist circumference had no significant relationship with DAL. No publication bias was found.Conclusion: Higher DAL is associated with increased BMI, SBP, and DBP. More studies are needed to find any relationship between DAL and lipid profile and glycemic factors.

Keywords:

Dietary Acid Load , Cardio-metabolic risk factors , Observational studies , Systematic review , Meta-analysis