The Bioavailability of Xanthohumol in Humans and the Influence of Formulation and Dose: Randomized Controlled Trial...

Xanthohumol is a prenylated chalcone, which is mainly found in hops. Experimental studies show a variety of cardioprotective effects for xanthohumol, but so far there are only a few controlled studies on the bioavailability and efficacy of xanthohumol in humans. In a randomized crossover bioavailability trial, the plasma kinetics of 86 mg and 172 mg each of micellar or native xanthohumol were investigated. Blood samples were obtained at fasting (t₀), regularly until 9 h and 24 h after oral xanthohumol bolus administration and the plasma concentrations of xanthohumol, xanthohumol glucuronide, and xanthohumol sulfate were analyzed. Micellation increased the area under the plasma concentration-time curve (AUC) (p < 0.001) and maximum plasma concentration (p <0.001). Both formulations showed a dose-dependent increase in xanthohumol maximum concentrations and AUC. The bioavailability was mainly influenced by micellation (p <0.001) and was approx. 9-fold higher after intake of micellar xanthohumol than after intake of the native form, irrespective of the dose (p = 0.480). A subsequent randomized placebo-controlled crossover bioactivity trial showed no acute effects of 172 mg micellar xanthohumol on resting energy expenditure, blood pressure, or heart rate. To conclude, bioavailability was significantly higher after ingestion of micellar xanthohumol than after ingestion of native xanthohumol.