Effects of Probiotics Supplementation on Short-Chain Fatty Acids: A Systematic Review of Randomized Controlled Trials

With the increased use of fermented products and probiotic foods, interest in knowing their benefits and safety of their intake is increasing.

The current systematic review investigated the effects of probiotics supplementation on short-chain fatty acid (SCFA) levels.

A systematic review was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Medline/PubMed, Scopus, Web of Science, and Embase databases were searched from inception to February 2024, including only randomized controlled trials.

A total of 30 studies were included, involving 1499 participants. The vast majority of trials investigated Bifidobacterium and Lactobacillus strains. These were categorized into healthy adults (n = 6), gastrointestinal/inflammatory diseases (n = 7), metabolic diseases (n = 6), elderly individuals (n = 3), children (n = 4), and infant formula (n = 4). Most studies evaluated isolated strain supplementation (n = 12), followed by fermented beverages (n = 11) and probiotic mixes (n = 3). Globally, 16 studies (53.3%) revealed an increase in at least 1 SCFA in participants supplemented with probiotics. In comparison, 5 studies (16.7%) reported a reduction and 9 studies showed no statistically significant impact in their findings (30%). The subgroup evaluation showed heterogeneity in the results, with low to moderate evidence grading levels.

Probiotics supplementation during childhood was the intervention period more effective in increasing fecal SCFAs and immunoglobulin A (IgA) levels (GRADE: moderate/high-certainty evidence).

PROSPERO registration no. CRD42024513221.