Synbiotics: Safety and Toxicity Considerations

This chapter describes the current knowledge regarding safety, toxicity, and applications of synbiotics in humans and animals. Synbiotics are now being considered important tools to help maintaining humans and animals in good health and in prevention and/or alternatives for reducing the risk associated to diseases. The majority of studies dealing with synbiotics are conducted in humans, but increasing research has been focused in animals. A full discussion of safety status of currently used synbiotics has been included. The well-designed and carefully conducted randomized controlled trials of synbiotics with relevant inclusion/exclusion criteria and adequate sample sizes are needed. These studies should use validated clinical outcome measures to assess the effects of synbiotic supplementation and define their optimal doses and intake durations, as well as provide more information about the long-term safety of synbiotics. Obligatory and standardized reporting on adverse events has been recommended in studies with synbiotics.