Effect of Atkins versus a low-fat diet on gut microbiota, and cardiometabolic markers in obese women following an energy-restricted diet: Randomized, crossover trial

Abstract

Background and aimsThere is controversy about effects of the Atkins diet on cardiometabolic markers in previous studies. No study compared effects of Atkins versus a low-fat diet on gut microbiota in obese women during a weight-loss program up to date. Methods and resultsA 6-week, randomized, crossover trial was conducted. Twenty-four healthy women with obesity (BMI≥30 kg/m2) were randomly assigned to receive the Atkins (55%, 25%, and 20% of total daily calories from fat, protein, and carbohydrates), or low-fat (20%, 15%, and 65% of total daily calories from fat, protein, and carbohydrates) diets while following a weight-loss program. Vegetable oils were used as the main source of dietary fat. Dietary groups were switched after two weeks of washout period with a weight maintenance low-fat diet. The effects of the two diets did not differ for the most endpoints. However, Gut Actinobacteria residency and serum total antioxidant capacity significantly increased in the Akins diet group compared with the low-fat one (p = 0.02 and p = 0.04). Adjusting for all parameters, gut Actinobacteria residency 1.48- and 2.5-folds decreased the serum LDL.C/HDL.C ratio and non-HDL.C levels (95%CI: 3.1, −0.22; p = 0.03 and −0.07, −0.002; p = 0.04), respectively. Decrease in gut Proteobacteria residency showed a significant reduction in serum total oxidant status (95%CI: 7.4, −0.07; p = 0.04). ConclusionsThe Atkins diet, based on vegetable oils, alters gut microbiota composition, atherogenic and antioxidant parameters. Registration number for clinical trialIRCT20200929048876N3.