How many studies support Sleep Quality?

The evidence base for this topic is comparatively weak and diffuse: available studies address related but distinct subjects, such as loneliness and sleep, herbal supplements (ashwagandha, lemon balm) and psychological well-being, and gut-brain-axis nutrition, none of which directly test structured interventions to improve sleep quality itself. That's backed by 4 published studies in Vitaebase's database, including 1 randomized controlled trial and 3 meta-analyses, the most recent from 2024 -- a modest but real research base.