D-tagatose, a stereoisomer of d-fructose, increases blood uric acid concentration

D-Fructose has been found to increase uric acid production by accelerating the degradation of purine nucleotides, probably due to hepatocellular deple tion of inorganic phosphate (P-i) by an accumulation of ketohexose-1-phosph ate. The hyperuricemic effect of D-tagatose, a stereoisomer of D-fructose, may be greater than that of D-fructose, as the subsequent degradation of D- tagatose-1-phosphate is slower than the degradation of D-fructose-1-phospha te. We tested the effect of 30 g oral D-tagatose versus D-fructose on plasm a uric acid and other metabolic parameters in 8 male subjects by a double-b lind crossover design. Both the peak concentration and 4-hour area under th e curve (AUC) of serum uric acid were significantly higher after D-tagatose compared with either 30 g D-fructose or plain water. The decline in serum P-i concentration was greater at 50 minutes after D-tagatose versus D-fruct ose, The thermogenic and lactacidemic responses to D-tagatose were blunted compared with D-fructose, D-Tagatose attenuated the glycemic and insulinemi c responses to a meal that was consumed 255 minutes after its administratio n, Moreover, both fructose and D-tagatose increased plasma concentrations o f cholecystokinin (CCK) and glucagon-like peptide-1 (GLP-1). The metabolic effects of D-tagatose occurred despite its putative poor absorption. Copyri ght (C) 2000 by W.B. Saunders Company.