Abstract

Background: Kefir, a fermented milk beverage, contains a diverse community of microorganisms that may enhance metabolic health and overall well-being in athletes. Its unique composition, enriched through fermentation, offers bioactive compounds that could influence digestion, immune function, and oxidative stress, which are critical for athletes facing intense training demands.
Materials and Methods: This narrative literature review article systematically analyzed studies from electronic databases, including PubMed, Scopus, and Web of Science, focusing on articles published from 2000 to 2025. The search utilized terms related to kefir, metabolic health, and athletic performance, encompassing both human and animal studies. Inclusion criteria prioritized original research, randomized controlled trials, and observational studies, while review articles provided supplementary context.
Results: The review identified evidence suggesting that kefir positively impacts lipid metabolism, glycemic control, inflammation, and antioxidant capacity. Additionally, it highlights improvements in gut barrier integrity and reductions in exercise-induced gastrointestinal symptoms, supporting the notion that kefir may enhance recovery and performance in athletes.
Conclusion: Kefir presents a promising functional food that may support metabolic health and psychological well-being in athletes through mechanisms such as antioxidant activity and gut-microbiome interactions. However, further empirical research is needed to substantiate these findings and explore practical applications in athletic populations.

Keywords:Kefir; Fermented milk; Athlete’ Well-being; Exercise; Metabolic health