BarthHaas Japanese researchers carried out a medical study for 3 weeks, during which they evaluated the effect of non-alcoholic beer containing 35mg of hop bitter acids (iso-alpha acids and humulinones) on people’s mood, sleep, quality, and work performance. They found that hop bitter acids significantly improved total mood state, including anxiety, depression, fatigue, and vigour compared with the control. Although further investigation is needed, the findings suggest non-alcoholic beer in daily life might become a good choice for maintaining mood states.