Move fast and break things, including people's GI tracts. The fact that Soylent powder is at "version 1.6" and causing these problems points to gross version number inflation. This is a showstopper. Rob Rhinehart asserts that the human body is "just chemicals," yet a vat of elemental hydrogen, oxygen, carbon etc. would seem to behave a little differently from a human body composed of reproducing cells and structured organs. His CS background has made him consider the body a narrowly deterministic system that requires a minimum of sanity-check testing before releasing it upon the world. We're the beta testers here. Real world, physical systems have vast amounts of variability that techies don't seem to appreciate. I won't be surprised to see VC funds starting to require deep involvement of health professionals for companies in the diet/medical space, especially in light of Theranos and now this.