A Randomized, Double-blind, Placebo-controlled Parallel Study of Effects of Food containing Hokkaido Scallop oil Plasmalogen, Gamma-aminobutyric acid, Piper longum on Fatigue and Stress

Abstract

This study was a randomized, double-blind, placebo-controlled parallel-group study that examined the effects of a 10-week course of supplements containing γ-aminobutyric acid (GABA), Hokkaido scallop-derived plasmalogen (HSOP), and Piper longum extract on mood, fatigue, and sleep quality after mental stress in healthy Japanese adults (aged 18–60). Using the Profile of Mood States 2 (POMS2), sleep quality using the Japanese version of the Pittsburgh Sleep Quality Index (PSQI-J), and secondary outcomes including the Epworth Sleepiness Scale (ESS) and a fatigue Visual Analogue Scale (VAS) were used to assess the supplement group and placebo group. As a result, the supplement group showed significant improvements in the POMS2 subscales of confusion-bewilderment, depression-dejection, fatigue-inertia, and tension-anxiety, as well as a reduction in the Total Mood Disturbance score compared to the placebo group. However, no significant differences were observed in PSQI-J, ESS, or VAS scores between the supplement group and placebo group. Moreover, safety monitoring, including self-reported questionnaires on bowel habits and lifestyle, as well as anthropometric measures, revealed no clinically relevant adverse events. These findings suggest that this multi-ingredient supplement may help alleviate temporary stress-induced mood disturbances and perceived fatigue in healthy adults.