Impact of Non-Digestible Carbohydrates and Prebiotics on Immunity, Infections, Inflammation, and Vaccine Responses: A Systematic Review
This systematic review looked at how non-digestible carbohydrates (NDCs), including prebiotics like GOS, FOS, inulin, and human milk oligosaccharides (HMOs), affect the immune system, infection rates, inflammation, and vaccine response. The authors analyzed 126 human studies across infants, children, adults, and older adults, including people with chronic health conditions. They grouped the studies by age, health outcomes (like infections, immune markers, and vaccine response), and type of supplement used.
The results showed that NDCs may help lower the risk or shorten the length of respiratory and gut infections, especially in infants and children. For instance, several infant formula studies with GOS/FOS blends found fewer cases of diarrhea and respiratory infections, and less antibiotic use. In adults, the results were more mixed. Some studies in older adults showed better vaccine responses and lower inflammation markers like CRP and TNF-α, but many trials in healthy adults showed little to no effect. The benefits seemed more likely in people under immune stress, like infants, the elderly, or those prone to infections, rather than in already healthy individuals.
Overall, the review suggests that certain prebiotics can support immune health, but the effects vary depending on age, health status, and the type of supplement. The most likely explanation for these benefits is that prebiotics help shape the gut microbiome and boost the production of helpful compounds like short-chain fatty acids. Still, many studies used different designs, doses, and outcome measures, making it hard to compare results. The authors call for better-designed studies that use consistent immune markers and longer timelines, especially in groups that are more likely to benefit. In short, prebiotics show promise for boosting immune defenses. Mainly in people who need it most.
