Most of the literature reviewed here has been secondary analyses of clinical trial data or observational data that have found associations between drugs that affect potassium levels, serum potassium, dietary potassium and foods that are high in potassium with diabetes risk. summarizes the associations found between markers of potassium and risk of incident diabetes as well as the level of evidence supporting these associations. Over 20 years ago, experimental hyperglycemic clamp studies demonstrated that potassium supplementation did improve insulin sensitivity of participants who had experimentally induced hypokalemia, but no randomized controlled trial has tested this effect in a larger population. The studies evaluating the effects of ACE inhibitors and ARBs on diabetes risk did not isolate the potential effect of changes in potassium levels on these associations. Furthermore, no clinical trials to our knowledge have evaluated the impact on potassium supplementation, either dietary or pharmacologic, in any population, on glucose metabolism.
Potassium is a vital electrolyte. Both high and low levels are already associated with various medical conditions, including hypertension, cardiac arrhythmias, osteoporosis and nephrolithiasis [16
]. It is plausible, given the evidence presented in this article, that potassium also has a significant role in diabetes mellitus. In observational studies, there are fairly strong associations between serum potassium and diabetes risk, with lower serum levels associated with increased risk. In observational studies, there is a suggestion that dietary potassium may be associated with diabetes risk. In studies involving both serum and dietary potassium, there is a suggestion that their effects on diabetes risk could vary based on race. These racial differences suggest that there could be genetic factors that could affect the association between lower potassium levels and diabetes risk. This could also mean that genetic factors may potentially influence the response to interventions designed to raise potassium levels.
Since most studies examining the association between potassium and diabetes risk have been observational in nature, experimental studies are needed to help clarify the effect of both serum and dietary potassium on diabetes risk. Interventions with potassium supplementation, either dietary or pharmacologic, should be systematically evaluated as potential novel intervention for the prevention and treatment of diabetes, particularly in high-risk populations.