Healthy Living / Eating
Probiotics May Help You Sleep Better
Feb
We usually recommend probiotics for gut health, but gut health actually affects the entire body. As an example, a new randomized controlled trial suggests that the probiotic strain Lacticaseibacillus paracasei PS23 can meaningfully improve sleep quality, though it fell short of reducing perceived stress.
The six-week study, published in Annals of General Psychiatry in October 2025, enrolled 45 office workers experiencing moderate to high stress levels. Participants took either 20 billion CFU of L. paracasei PS23 or a placebo daily. While the probiotic group saw no significant reduction in stress compared to placebo, they did experience notable improvements in overall sleep quality. Specifically, participants in the probiotic group fell asleep faster, stayed asleep more easily, and showed improvements in trait anxiety (the baseline tendency to experience anxious feelings, as opposed to situational anxiety triggered by specific events).
The results echo findings from a 2022 study of clinical nurses under high stress, which also examined PS23. That earlier trial found anxiety improvements were limited to participants with the highest stress levels, suggesting the strain’s effects may depend on who’s taking it and what you’re measuring.
The gut-brain axis (the bidirectional communication network between the digestive system and the central nervous system) has become one of the more promising areas of nutritional research. Probiotics that influence this pathway, sometimes called “psychobiotics,” are of particular interest for their potential effects on mood, anxiety, and sleep. PS23 appears to sit in this category, though the evidence base remains thin.
The takeaway? If you’re struggling with sleep quality, probiotics (in particular, L. paracasei PS23) may be worth watching as more research develops. But anyone hoping a single probiotic will meaningfully reduce their stress levels should temper expectations. As with most things in the supplement world, the answer is nuanced, and more data is needed.
