Do we choose control diets wisely?

In a recent article in Cell Reports, Dalby and colleagues convincingly demonstrate that choosing an inadequate control diet in animal experiments that investigate the interaction of nutrition, gut microbiota, and obesity development may lead to the wrong conclusions. The authors systematically compared the effects of refined high- and low-fat diets (rHFD and rLFD) with those of a standard chow diet on mouse physiology, microbiota composition, cecal fermentation, and intestinal morphology. The results obtained in this study question the conclusions drawn from animal studies that compared the effects of HFDs with those of chow diets.