Comparing the efficacy of apple peels and a sodium-glucose cotransporter 2 inhibitor (ipragliflozin) on interstitial glucose levels: A pilot case study

BACKGROUND: Apple peels contain phlorizin, which can reduce plasma glucose levels in a manner similar to that of inhibitors for sodium-glucose cotransporters. OBJECTIVES: In this study, we examined the influence of a peeled apple, a sodium-glucose cotransporter-2 inhibitor (ipragliflozin) in combination with a peeled apple, and an unpeeled apple on interstitial glucose in a healthy individual across 3 experiments. METHODS: For Experiments 1, 2, and 3, the healthy volunteer consumed 327 g peeled Sun Fuji apple, took 50 mg ipragliflozin, and then consumed 327 g peeled Sun Fuji apple, or consumed 370 g unpeeled Sun Fuji apple (peel weight was 43 g), respectively. In each condition, the apple was eaten within a 15-minute period and interstitial glucose levels were measured every 15 minutes for 11.5 hours using FreeStyle Libre (Abbott Laboratories, Abbott Park, Illinois). RESULTS: Results showed that neither consumption of the unpeeled apple nor ipragliflozin were able to suppress the rapid or transient increases in postprandial glucose; however, the 2 were found to comparably suppress interstitial glucose during the late phase. CONCLUSIONS: On the whole, these findings demonstrate that eating unpeeled apples may be beneficial for plasma glucose management, but ipragliflozin is a superior option because the apple peel's function did not last as long as ipragliflozin. (Curr Ther Res Clin Exp. 2020; 81:XXX–XXX)