Scientific interest in probiotics continues to grow. In fact, the number of PubMed publications with the combined terms ‘probiotics’ and ‘gut microbiota’ has increased 98-fold since 2001, the year we held our first International Yakult Symposium in Europe and the year the current probiotic definition was formulated by the FAO/WHO working group. During this time, we have learnt many new things about the interactions occurring in the microbial community and their influence on the organs of the host, including the mechanisms of the interplay with external elements such as pro- and prebiotics. But as more is discovered, the areas under investigation broaden. We are just starting to scratch the surface of the complex interactions between the microbiota and the host and clearly a lot remains to be explored.

During the 9th International Yakult Symposium we seek to answer fundamental questions like: what is “normal” or “healthy” when talking about our gut microbiota? Does host genetics shape the gut microbiota? How important is epigenetics in this, and can we transfer these properties or experiences to our children? How do bacteriophages interact with probiotics? Can we really predict the efficacy of probiotics using in vitro models? Can a probiotic influence students’ performance under exam pressure?

These and many other questions on probiotics, gut microbiota and health will be reviewed by experts in the respective fields. Similar to the previous editions, this symposium will provide an opportunity for students, young investigators and established scientists to develop understanding, engage in scientific debate, and network with experts and colleagues in this extremely interesting field of microorganisms and health.  We count on you for comments and discussion!