Short-chain fatty acids as anti-inflammatory agents in overweight and obesity: a systematic review and meta-analysis

Abstract

Context: Short-chain fatty acids (SCFAs) derived from microbial fermentation of prebiotic soluble fibers are noted for their anti-inflammatory benefits against obese systemic inflammation.

Objective: A systematic review and meta-analysis were undertaken to investigate the effect of SCFAs and prebiotic interventions on systemic inflammation in obesity.

Data sources: Relevant studies from 1947 to August 2019 were collected from the Cumulative Index to Nursing and Allied Health Literature, Embase, Medline, and Cochrane databases. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed.

Study selection: Of 61 included studies, 29 were of humans and 32 of animals.

Data extraction: Methodological quality of studies was assessed using the critical appraisal checklist of the Academy of Nutrition and Dietetics. Data pertaining to population, intervention type and duration, and markers of systemic inflammation were extracted from included studies.

Results: Of 29 included human studies, 3 of 4 SCFA interventions and 11 of 25 prebiotic interventions resulted in a significant decrease in ≥1 biomarker of systemic inflammation. Of 32 included animal studies, 10 of 11 SCFA interventions and 18 of 21 prebiotic interventions resulted in a significant reduction of ≥1 biomarker of systemic inflammation. Meta-analysis revealed that prebiotics in humans reduced levels of plasma high-sensitivity C-reactive protein (standard mean difference [SMD], -0.83; 95%CI: -1.56 to -0.11; I2: 86%; P = 0.02) and plasma lipopolysaccharide (SMD, -1.20; 95%CI: -1.89 to -0.51; I2: 87%; P = 0.0006), and reduced TNF-α levels in animals (SMD, -0.63; 95%CI: -1.19 to -0.07; P = 0.03). Heterogeneity among supplement types, duration, and dose across studies was significant.

Conclusion: Evidence from this review and meta-analysis supports the use of SCFAs and prebiotics as novel aids in treatment of obese systemic inflammation.

Systematic review registration: PROSPERO registration no. CRD42020148529.

Keywords: inflammation; obesity; prebiotics; short-chain fatty acids.