This is a randomized, double-blind, placebo-controlled, parallel group study, designed to assess the effectiveness & safety of the B. longum 1714™ strain, when consumed once daily, on sleep quality. The 8-week intervention study will be conducted in otherwise healthy participants with a Pittsburgh Sleep Quality Index (PSQI) score of greater than, or equal to 5, a HADS-A and HAD-D score less than or equal to 14 and an Insomnia Severity Index of less than 11. Participants (N=90) will be pre-screened online, then visit the study site 4 times during the course of the 8 - 10 weeks' study (2 weeks screening period, followed by 8-week intervention). The first visit will be for screening, second visit will be baseline (and start of intervention - either active or placebo), third visit will be mid-intervention, and fourth visit will be at the end of intervention. Questionnaires will be administered at visit 2, 3 and 4, and research blood and saliva will also be collected at these time points. Hair sample will be taken at visit 2 and 4 while stool sample will be collected at visit 4. Participants will wear an actigraph and fill in a sleep eDiary for the whole intervention period (from visit 2 to visit 4).
The aim of this study is to evaluate the effect of supplementation with the B. longum 1714™ strain on subjective and objective sleep quality in healthy participants.