The anomeric specificity of D-glucose metabolism and functional effects is currently assessed either over about 5 min at 37 degrees C or longer periods at much lower temperatures. In the present study, the half-life for the interconversion of D-glucose anomers at 30 degrees C was found to be increased (P<0.005) from 17.2+/-0.9 min in a mixture of H2O/D2O (9/1, v/v) to 58.6+/-1.9 min in pure D2O. It is proposed that advantage can be taken from this delayed interconversion in D2O in experiments dealing with the anomeric specificity of D-glucose metabolic fate and functional effects. Thus, even over 60-min incubation at 30 degrees C, the integrated mean abundance of alpha- and beta-D-glucose would remain close to 82 and 89%, respectively, of the corresponding initial value (100%).