The microbiome is arguably the most intimate connection that humans have with their external environment, mostly through diet.
- A major recurring theme of the workshop discussion was the very intimate connection that the human microbiome has with both its human host and its host’s external environment. Diet appears to be the most important environmental modulator of the microbiome, with significant implications for human health and disease. As scientists continue to learn about the impact of diet on the microbiome and the consequences of that impact for human health and disease, the food industry is using that newfound knowledge to develop novel products for building and maintaining health via their impact on the microbiome.
Given the emerging nature of research on the microbiome, some important methodological issues still have to be resolved with respect to undersampling (i.e., some workshop participants expressed concern not just about underpowered studies, but also about tissue undersampling) and a lack of causal and mechanistic studies.
- In almost every open discussion, individual workshop participants or audience members expressed concern about the danger of making predictions about diet-microbiome-health relationships based on studies with small samples sizes. For example, Ellen Silbergeld said, “I think the comments that have been raised throughout this meeting about how we’re really dealing with a very small edge of knowledge when we talk about the microbiome in any specific domain should give us pause when we make predictions as to what is going to happen.” She remarked that small studies are helpful for formulating new hypotheses, but they are not sufficient for translating science into public health. She and others cautioned that “large- N” studies will be needed in the future. Johan van Hylckama Vlieg and other participants agreed that more large-N studies are needed but emphasized that small-N studies serve an essential exploratory