The Psychophysiological Effects of a Kombucha Intervention to the Maastricht Acute Stress Test

Kombucha, a fermented tea beverage containing probiotics and bioactive compounds, has been associated with various health benefits, including the potential to have stress-reducing benefits. The study examined whether 8-week Kombucha consumption modulates physiological and subjective stress responses during the Maastricht Acute Stress Test (MAST). In a placebo-controlled design, healthy participants (N = 40, 20-72yrs) either consumed a Kombucha or a placebo beverage daily, completing pre- and post-intervention MAST sessions. Stress and pain reactivity was measured using standard psychophysiological and/or self-report indices while controlling for individual differences. The MAST elicited a significant main effect of increased sympathetic activity response to the stressor, confirming effective stress induction. A significant time effect was observed, reflecting the dynamic nature of stress responses throughout the MAST. No significant main effect of beverage or interaction between beverage and time was found. Analysing the change between sympathetic and parasympathetic activity (change from stress to no stress) and controlling for gender, results suggest a group main effect, with the kombucha group showing the least amount of change in the autonomic nervous system, but no group by time interaction. The MAST effectively provoked the desired stress responses. While change in autonomic nervous activity was reduced in individuals in the Kombucha group (pre and post intervention). These findings do not support a stress regulation role for Kombucha under laboratory conditions.