The effect of a low renal acid load diet on blood pressure, lipid profile, and blood glucose indices in patients with type 2 diabetes: a randomized clinical trial

BACKGROUND: Observational studies have reported that dietary renal acid load has an important role in insulin resistance and metabolic factors. The aim of the present study was to assess the effect of a low renal acid load diet (LRALD) on blood pressure, lipid profile, and blood glucose indices in patients with type 2 diabetes. METHODS: In this parallel randomized clinical trial, 80 patients with type 2 diabetes were randomly assigned to the LRALD (n = 40) or control (n = 40) groups, for 12 weeks. Both groups received a balanced diet and a list of nutritional recommendations based on healthy eating behaviors. In the LRALD group, food items with low renal acid load were prescribed. Primary outcomes including: fasting blood glucose (FBG), hemoglobin A1c (HbA1c), fasting serum insulin, quantitative insulin sensitivity check index (QUICKI), homeostatic model assessment for insulin resistance (HOMA) and secondary outcomes including: weight, systolic blood pressure (SBP), diastolic blood pressure (DBP), triglyceride (TG), total cholesterol (TC), low-density lipoprotein (LDL), and high-density lipoprotein (HDL). were measured at baseline and end of the study. The present trial was registered at IRCT.ir (IRCT20130903014551N5). RESULTS: Seventy subjects completed the study (n = 35 in control group and n = 36 in LRALD). Weight (P < 0.001), body mass index (P < 0.001), FBG (P < 0.001), HbA1c (P < 0.001), SBP (P = 0.004), and TG (P = 0.049) were reduced and HDL (P = 0.002) was increased in both groups, compared with baseline. After adjusting for baseline values, DBP (P = 0.047) was reduced in the LRALD group compared with control group. Results had no changes after using intention to treat analysis. CONCLUSION: A LRALD may decrease DBP in type 2 diabetic patients. However, it elicited no significant effect on lipid profile compared with a healthy diet. TRIAL REGISTRATION: This randomized clinical trial was registered at IRCT.ir (IRCT20130903014551N5). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12937-023-00849-6.