Fasting urine pH is independent of insulin sensitivity.

BACKGROUND It has recently been suggested that a low urine pH be added to the abnormalities linked to insulin resistance. This conclusion is based on the finding of a low urine pH in individuals with clinical syndromes associated with insulin resistance and not on studies in which a direct measure of insulin sensitivity was shown to be significantly related to differences in urine pH. OBJECTIVE To address this issue, we quantified insulin-mediated glucose uptake (IMGU) by using the insulin suppression test in 96 apparently healthy, nondiabetic individuals and defined its relation to fasting urine pH. DESIGN Urine samples were collected and analyzed from a cohort of healthy subjects within a narrow body mass index range who were recruited to determine insulin sensitivity. RESULTS There was an approximate 6-fold variation in values for IMGU in this population, with no relation to urine pH (r = 0.02). Furthermore, there was no relation between body mass index, as a surrogate estimate of insulin resistance, and urine pH (r = 0.06). CONCLUSION On the basis of these findings, we question the view that a low urine pH be added to the abnormalities linked to insulin resistance in low-risk populations.