健常成人におけるGABA 経口摂取が睡眠に与える影響―無作為化二重盲検プラセボ対照クロスオーバー試験―

Objectives This study aims to evaluate the effects of orally administrated GABA for 2 consecutive weeks on stress, sleep quality, fatigue, and electroencephalography during sleep compared to placebo. Methods A total of 32 subjects received, in random order, 100 mg of GABA or placebo 30-60 minutes before bedtime. A crossover design was used so that each subject received each of the 2 foods for a 2-week period（with a 2-week washout period between）. Electroencephalograms were recorded during sleep at home with a portable device. This study was registered in UMIN-CTR（UMI26673）. Results GABA significantly decreased the total non-rapid eye movement（non-REM）sleep stage 2. In stratified analysis based on stress, the total time of non-REM sleep stage 3 in the layer above the mean value of confusion-bewilderment, anger-hostility, tension-anxiety, total mood disturbance score of the Profile of Mood States 2nd edition（POMS2）were significantly increased in the GABA intake period compared to the placebo. In stratified analysis by fatigue feeling, the total time of non-REM sleep stage 3 at the time of ingesting GABA in the layer where the fatigue VAS prior to ingestion exceeded the average value significantly increased compared to placebo. Stratified analysis based on age, the total time of non-REM sleep stage 3 at the time of ingestion of GABA in the stratum above the average age was significantly increased compared to placebo. Conclusions These results indicate that oral administration of GABA increases the time of deep non-REM sleep of those who feel strong psychological stress or fatigue and╱or those who middle-aged and elderly.