Mediterranean, low-fat, high complex carbohydrate diets focus of study.
Long-term dietary interventions following a specific diet may influence gut microbiota, which plays a major role in the host metabolism. Limited studies exist on how gut microbiota changes with specific diets and its influence on health outcomes. Therefore, researchers are interested to study the changes in microbiota after one year’s consumption of a Mediterranean diet (Med diet) or a low-fat, high-complex carbohydrate diet (LFHCC diet) in an obese population.
Researcher Antonio Camargo Garcia, PhD, of Sofia University Hospital and the University of Cordoba in Spain, and colleagues examined a subgroup from the CORDIOPREV study, which is an ongoing prospective, randomized, open, controlled trial in patients with coronary heart disease. The subjects were 20 obese men (average BMI of 32 kg/m^2 and an average age of 63 years). Apart from receiving CHD treatment, these subjects were randomly assigned to consume a Med diet or a LFHCC diet. Researchers analyzed microbiota on 40 fecal samples, 20 taken at baseline and 20 after one year of dietary adherence. Analysis of the bacterial consumption of these samples and the relationship between the diets, gut microbial ecology and changes in fecal and plasma metabolites were examined.
It was found that adherence to the LFHCC diet resulted in an increased relative abundance of Prevotella bacterial genus. On the other hand, the Med diet resulted in a decrease. Furthermore, the Med diet was linked with an increase in Roseburia and Oscillospira. The LFHCC diet was linked with a decrease of Roseburia and no change in Oscillospira. Long-term consumption of the Med diet resulted in an increase of Parabacteroides distasonis and the LFHCC diet increased Faecalibacterium prausnitzii.
Authors believe that the detection of 572 compounds in the feces, with 37 showing significant interaction between time and diet, is important to understand the potential role of gut microbiota when used as a therapeutic tool in human health. However, further studies are warranted to fully understand the microbial functions when modified by diet in the prevention of metabolic diseases.
The results suggest that a long-term consumption of the Med and LFHCC diets exert a protective effect on the development of type 2 diabetes by different specific changes in the gut microbiota, increasing the abundance of the Roseburia genus and Faecalibacterium prausnitzii, respectively.
- Long-term consumption of the Med and LFHCC diets may exert a protective effect on the development of type 2 diabetes by different specific changes in the gut microbiota.
- The protective effect on type 2 diabetes through changes in gut microbiota is observed relative to an increase in the abundance of the Roseburia genus and Faecalibacterium prausnitzii.
- Further studies are required in order to fully understand the microbial functions and the potential role of gut microbiota modification by diet in the prevention of metabolic diseases.
Haro, Carmen, et al. “Two healthy diets modulate gut microbial community improving insulin sensitivity in a human obese population.” The Journal of Clinical Endocrinology & Metabolism (October 27, 2015): jc-2015.