The science of HMOs: What they are and what they do

Human milk oligosaccharides (HMOs) are a group of complex carbohydrates that are highly abundant in human milk and contribute to shaping the infant’s gut microbiome and immune system for immediate and long-term health benefits. New research has been shown that certain HMOs can have a role in reducing the risk of infectious diseases, immune development and on neurodevelopment and cognition. Sometimes specific individual HMOs are effective, because the effects are highly structure-specific and the mechanisms are likely receptor-mediated. While sometimes specific HMO mixtures are effective, thereby a relative abundance of HMOs and or the ratio of HMOs matters. The mechanisms of action is likely indirect. In any case, a combination of pre-clinical, cohort and clinical trials is required to fully assess and validate the effects and functions of HMOs.