of nutrition in the Human Microbiome Project 2 (HMP2), if and when HMP2 is funded.
There was also some discussion about the usefulness of better understanding the impact of the microbiome on host energetics. Fahey suggested that there might be lessons to be learned from studying microbial metabolism in cows and pointed to work done in that area by Marvin Bryant and Robert Hungate. Johan van Hylckama Vlieg suggested that simplified systems models might help to better understand the microbial role in energy metabolism in humans. He said that probably a few core metabolic pathways are major determinants for the impact of the microbiome on host metabolism. Building a systems-level model of gut ecosystem that functions with these core pathways could reduce some of the puzzlement caused by the vastness of the microbiome metagenome and help to better understand clinical observations.
With respect to the challenge of health (versus disease) food claims, not all workshop participants agreed that the next best step is to shift the science toward collecting data in healthy populations in order to substantiate those health claims. One audience member agreed that all of the disease-related research on the microbiome described over the course of the 2-day workshop is “great science” and that “the science will continue to go forward,” but the greater challenge, he said, is that “we are still left with a 1938 regulatory environment” and regulatory authorities are “hamstrung by whatever the law tells [them]. That is all [they] can act on.” He referred to Sarah Roller’s suggestion that “maybe we should think about how to change that law.” (See the Chapter 6 summary of Sarah Roller’s presentation for a description of her views on what she perceives as an outdated regulatory framework for food claims.) Especially given that the science is moving in the disease direction and there will probably come a point when “we may be able to treat or mitigate disease by virtue of foods,” the speaker urged that steps be taken now to change the regulatory framework in preparation for the future. Otherwise, how will the value of what scientists discover be communicated? Stuart Craig agreed and said, “The current regulatory environment is paralyzing for industry … we need to start now” (see Figure 7-1).
Peter Turnbaugh cautioned that drawing a hard line between disease and health is “a very dangerous way to think about the way we study” the microbiome. In his opinion, most biologists are interested in fundamental mechanisms. While they hope that their research findings will have helpful applications, that is not the underlying goal of science. Clydesdale