Background

Put differently, the primary substance that feeds “beneficial” gut microbes is “microbiota-accessible carbohydrates” (17), and in the absence of these, protein and fat will deteriorate our gut health. One of the most cited studies used to support this consensus is that of David et al. (18). While this study demonstrates how quickly the human gut microbiota adapts to dietary changes, what is less clear is how this should be interpreted (9). We are still far from being able to precisely define a “healthy” gut microbiota (21–25), and it is quite likely that the human gut and its microbial symbionts evolved to adapt to a variety of macronutrient patterns. …