Associations between Dietary Acid-Base Load and Cardiometabolic Risk Factors in Adults: The Tehran Lipid and Glucose Study

BACKGROUND: In this study we investigated the associations of dietary acid-base load, identified by potential renal acid load (PRAL) and protein to potassium (Pro:K) ratio, with cardiometabolic risk factors in Tehranian adults. METHODS: A cross-sectional study was conducted within the framework of the fourth phase of the Tehran Lipid and Glucose Study (2009 to 2011) on 5,620 men and women aged 19 to 70 years. Dietary data were collected by a trained dietitian using a validated, 147-food item, semi-quantitative food frequency questionnaire, and dietary PRAL and Pro:K ratio were calculated. Multiple linear regression models with adjustment for potential confounding variables were used to evaluate the associations of dietary acid-base load with anthropometric measures, blood pressure, serum triglycerides, high density lipoprotein cholesterol (HDL-C), serum creatinine, and fasting blood glucose. RESULTS: The mean±SD age of the participants was 39.8±12.8 years and 54% of participants were women. Mean±SD PRAL was -22.0±29.1; mean PRAL was -15.6 in men and -26.8 in women. Dietary PRAL was associated with weight (β=0.098, P<0.001), waist circumference (β=0.062, P<0.01), serum triglycerides (β=0.143, P<0.01), HDL-C (β=-0.11, P<0.01), diastolic blood pressure (β=0.062, P<0.01), and serum creatinine (β=0.142, P<0.001). Pro:K ratio was associated with weight (β=0.055, P<0.001), waist circumference (β=0.04, P<0.01), serum HDL-C (β=-0.06, P<0.01), serum triglycerides (β=0.03, P<0.05), diastolic blood pressure (β=0.026, P<0.05), and serum creatinine (β=0.07, P<0.01). CONCLUSION: A more acidic dietary acid-base load may be a risk factor for the development of metabolic disorders.