Objectives　The aim of the study was to investigate the effects of food containing asparagus extract（ONR-8）on sleep conditions in evening-type individuals.
Methods 　We conducted a randomized, double-blind, placebo-controlled, crossover, exploratory study in 20 healthy male volunteers who had an evening-type chronotype. In Period 1, participants were randomly assigned to take either ONR-8 or placebo for 2 weeks. In Period 2, the treatments were reversed in a crossover manner. To assess performance, participants took the Psychomotor Vigilance Test（PVT）twice: once in the morning and once after lunch at 0, 1, and 2 weeks of treatment. They also completed the Athens Insomnia Scale（AIS）, the Epworth Sleepiness Scale（ESS）, a visual analogue scale（VAS）for morning appetite, the Morningness- Eveningness Questionnaire（MEQ）, and SF-36. In addition, autonomic nerve function and expression of Heat Shock Protein（HSP）70 mRNA in peripheral blood leukocytes were measured. Participants were asked to complete the OSA sleep inventory MA version during the study period and to record sleep parameters by actigraphy for 3 days prior to intake and continuously during the study period.
Results　The AIS score during the period of ONR-8 intake was significantly improved as compared with the placebo intake period. When we analyzed the PVT data excluding participants who fell asleep during the test, a significantly faster reaction time on the PVT after lunch was observed during the intake of ONR-8. There were no adverse clinical events throughout the study period.
Conclusions　These results suggest that ONR―8 improved sleep and daytime performance in evening―type individuals.