Probiotics, paraprobiotics offer no clear sleep benefits

Currently, there is not enough evidence to support taking probiotics or paraprobiotics to help with subjective or objective sleep quality, reports a new meta-analysis. More studies with better experimental designs are needed to probe the subject further.

From the online databases of PubMed, Web of Science, Scopus, and PsycINFO, 14 studies corresponding to 20 trials were retrieved and deemed eligible for meta-analysis. In the included reports, sleep was assessed using the Pittsburgh Sleep Quality Index (PSQI), electroencephalography (EEG), actigraphy, and subjective patient responses.

A meta-analysis of 11 trials (n=452) found that taking probiotics or paraprobiotics led to an overall significant improvement in PSQI score (mean difference [MD], 0.78, 95 percent confidence interval [CI], 0.395–1.166; p<0.001), with low evidence of heterogeneity. This result was stable to sensitivity analysis, where each trial was removed individually.

In eight trials (n=549), however, the researchers found no significant impact of probiotics or paraprobiotics on subjective ratings of sleep quality (p=0.462). This finding was likewise of low or moderate heterogeneity and remained robust to sensitivity analysis. Similarly, sleep efficiency (six trials; p=0.976) and sleep latency (seven trials; p=0.509) were unaffected by probiotics or paraprobiotics.

Though slight changes in the magnitude of PSQI were observed, the overall principal findings remained unchanged during subgroup analysis.

“While the current evidence suggests that consuming probiotics/paraprobiotics does not significantly influence responses on other subjective sleep scales; nor does it influence sleep efficiency and sleep latency measured objectively using PSG and actigraphy, the number of well-designed research investigations is presently limited,” the researchers said.

“Hence, further research, specifically employing objective sleep outcome measures using well-controlled, within-subject experimental designs, and both homogenous and heterogenous populations are needed,” they added.