Short term effects of coffee components consumption on gut microbiota in patients with non-alcoholic fatty liver and diabetes: A pilot randomized placebo-controlled, clinical trial.

The aim of this study was to determine the effects of caffeine and chlorogenic acid supplementation on gut microbiota, and metabolic disturbances in patients with NAFLD and diabetes. In this randomized, placebo-controlled, clinical trial, 26 patients with diabetes and NAFLD were randomly assigned to four groups to receive either 200 mg caffeine plus 200 mg chlorogenic acid (CFCA), or 200 mg caffeine plus 200 mg placebo (starch) (CFPL), or 200 mg chlorogenic acid plus 200 mg placebo (CAPL), or 200 mg placebo plus 200 mg placebo (PLPL) for 12 weeks. After 3 months of supplementation, patients in the intervention groups showed a significant decrease in body weight (CFCA group =-3.69 kg; CFPL group=-0.7kg; CAPL group=-0.43kg; PLPL group=0.26 kg) (p=0.004). Weight reduced significantly more in CFCA group compared to all other three groups (p=0.005 for PLPL; p=0.023 for CAPL; and p=0.031 for CFPL). Although the number of gut Bifidobacteria increased in CFCA group, there were no statistically significant differences within and between the groups in any of bacteria numbers. In conclusion, our study showed that 12 weeks consumption of 200 mg/day caffeine plus 200 mg/day chlorogenic acid is effective in reduction of weight in patients with NAFLD and diabetes which might be at least partially through the rise in gut Bifidobacteria. This pilot study shed a light on the pathway of future clinical trials assessing the effects of coffee consumption in these patients. This trial has been registered at clinicaltrial.gov with registration number of NCT02929901.