Impact of Dietary Acid Load on Pancreatic β-cells Function and Insulin Resistance in Type 2 Diabetic Nigerians

Abstract

Background: The possible impact of high intake of dietary acid on pancreatic β-cells dysfunction and insulin resistance in type 2 diabetic patients has been suggested from previous studies; but findings across different study groups are conflicting.

Objective: To determine the impact of dietary acid load on pancreatic β-cell dysfunction and insulin resistance in a group of patients with uncomplicated type 2 diabetes mellitus.

Method: Study subjects were categorized in to four quartiles according to their dietary acid intake. Assessment of dietary intake was done using a food frequency questionnaire and the Nigerian Food Composition Table. Acid forming potential of our local diets were estimated as Potential Renal Acid Load (PRAL) scores. Pancreatic β-cell function and insulin resistance were estimated as HOMA-β and HOMA-IR respectively.

Results: Degree of pancreatic β-cells function was observed to be significantly lower in subjects in the highest quartile of the PRAL score (p for trend < 0.05). There was a statistically significant trend with higher intake of dietary acid associated with increased degree of insulin resistance (p for trend< 0.05). Dietary acid load was found to be a significant predictor of pancreatic β-cells dysfunction among the study subjects.

Conclusion: Among subjects with type 2 diabetes mellitus in this study, consumption of a diet loaded with high acid forming potential food items was associated with greater insulin resistance and lower insulin secretion ability. High intake of dietary acid might be an additive mechanism contributing to deterioration of glycemic control in type 2 diabetic patients in our setting.