Decaffeinated Coffee Consumption and Renal Function Impairment in Health and Diabetes: A Paradigm-Shift

Abstract

Aim: The belief that decaffeinated coffee (DCAF) does not contain a physiologically relevant concentration of caffeine and therefore has no significant adverse effect on renal endpoints makes patients who are vulnerable to renal dysfunction, renal compromised state, medical conditions that contraindicate caffeine intake or those already on prescription medications known to adversely affect the kidney to sometimes substitute DCAF for caffeinated coffee even as the credibility of this paradigm remains disputable. Therefore, the present study aimed to assess the effect of DCAF consumption on markers of renal function and carbohydrate metabolism in health and diabetes. Materials and Methods: Sixty Wistar Albino rats were divided into 12 groups (6pairs) (n=5per group) for male and female animals. Animals in group 1 served as normal control (NCTRL) and were given standard feed and water only. Animals in group 2 received standard feed plus DCAF. Group 3 was the diabetic (DIA) only group while groups 4, 5, and 6 were DIA plus DCAF treatment groups. After 4weeks of treatment, animals were sacrificed and blood obtained and analyzed for the biochemical indices of renal function and carbohydrate metabolism using standard methods. Results: Serum creatinine (SCr) levels increased significantly in all DCAF treated groups compared with the NCTRL group in male and female animals. Serum electrolytes did not show any significant change across groups. Serum Urea (SUr) increased and decreased in DIA alone group and DIA plus DCAF groups respectively. Serum glucose, insulin, and HOMA-IR increased and decreased significantly in DIA alone group and DIA plus DCAF treated groups respectively compared with NCTRL and DCAF control groups. Conclusion: The consumption of DCAF may adversely affect renal endpoints in health and diabetes but improves markers of carbohydrate metabolism in diabetes likely due to the re-enforcement effect of its caffeine and other bioactive constituents.