Low-carbohydrate hypo calorie diet has a beneficial effect on gut phyla and metabolic markers in healthy women with obesity: A randomized crossover study

Abstract

Despite the proven correlation among the gut microbiota, diet and weight, very few studies have studied the effects of very low carbohydrate and very low calorie diets on gut phyla. There is no study to compare the effect of low carbohydrate (LC) vs. low fat (LF) diet in a weight loss program on gut phyla. In a randomized crossover study, forty obese women (BMI≥30 kg/m 2 ) were categorized to receive LC (55% fat, 25% protein, and 20% carbo) or LF (20% fat, 15% protein, and 65% carbo) diet for six weeks while following a weight loss program. A two week washout period was considered between the diets. Mean difference of waist circumference and WHR were significantly higher in LC compared with LF group. Positive bacteriodetes and firmicutes patients were not significantly different in two groups, before and after the study. Positive actinobacteria patients were significantly increased in LC vs. LF group at the end (p = 0.02). In LC group, positive actinobacteria patients were significantly increased after six weeks (p = 0.003). Positive proteobacteria patients were significantly decreased in LC compared with LF diet (p = 0.04). Moreover, positive proteobacteria patients were significantly decreased in LC group (p = 0.005). Adjusting for dietary type, a significant relationship was seen between the serum LDL.C and proteobacteria residence in the gut (95%CI: 0.005–0.039, p = 0.01). In the LC group, positive actinobacteria and proteobacteria patients were significantly increased and decreased, respectively. • Low carbohydrate diet increased Actinobacteria residency in the intestine. • Low fat diet increased Proteobacteria , as the dominant phylum for metabolic disorders. • Serum LDL.C showed a relationship with Proteobateria residency in the gut, adjusted for diets.