Sucrose Matters. The Need to Make Groups Truly Comparable When Assessing Changes Associated with Insulin Sensitivity. Comment on Consumption of Cooked Black Beans Stimulates a Cluster of Some Clostridia Class Bacteria Decreasing Inflammatory Response and Improving Insulin Sensitivity. Nutrients 2020 12(4) 1182

摘要

The recent paper by Sanchez-Tapia et al. [ ] offers interesting results that should be taken with caution due to problems in the study design. The study compares groups of rats fed with Casein (C) or cooked Black Beans (BB), with and without a high-fat (HF) diet (i.e., 17g of lard). The main problem with the methodology lies in the composition of the diets, as they differ not only in the addition of lard but also in the amount of casein (present only in the C and C+HF group); the amount of cornstarch (41 vs. 23.97 in the C and C+HF groups, respectively); and, most notably, the amount of sucrose provided to the animals. Even though their composition of lipids, proteins, and carbohydrates are similar, the high amount of lard does have an effect on hypothalamic insulin signaling [ ]. Authors show in their Table that C and C+HF groups received 10 and 7.8 g of sucrose in the diet, while BB and BB+HF received 1.3 g and 0 g of sucrose, respectively. Despite the total carbohydrate content being similar, the difference in sucrose intake is of outmost importance as the effect of sucrose in insulin response has been long known [ , ]. This brings problems with the Results, as this sucrose intake difference could certainly explain the findings of rats on C and C+HF gaining significantly more weight and higher glucose levels than the BB and BB+HF groups, shown in the study.