The Influence of a Microbiome Immunity Formula on Alteration of Anthropometric and Glycemic Indices and Modulation of Gut Microbiome in Obese Young Individuals in Hong Kong: A Randomized, Double-blinded, Placebocontrolled Study.

Obesity is a global epidemic, and is an important cardio-metabolic risk factor associated with many non-communicable diseases, such as coronary artery disease (CAD), diabetes and non-alcoholic fatty liver diseases (NAFLD) (1-6). In 2010, our team recruited a cohort of obese adolescents [mean age at baseline: 17.2 years, mean body mass index (BMI): 30.9 kg/m2] from school surveys (7). Our group has examined the impact of dietary intervention using low glycemic index (GI) diet to reduce body weight of adolescents. We have reported that participants in the low GI group had a significantly greater reduction in obesity indices namely waist circumference after 6 months of intervention compared to counterparts in usual diet counselling group. We recently conducted a phone interview of the participants and most, if not all, of them remained obese from self-reported body weight. Pharmacological treatment options for obese individuals are limited (8-10). Amassing evidence showed that the gut microbiota plays an important role in energy harvesting and lipid metabolism. Gut microbiota dysbiosis was repeatedly reported in patients with obesity (11-13). Studies in humanized mouse models suggest that the obese gut microbiota was more efficient in harvesting energy from diet and may be a causative factor in the pathogenesis of metabolic disorders, including obesity, type 2 diabetes and NAFLD (14). Therefore, modulation of microbiota might be a potential strategy for prevention and treatment of metabolic disorders. Microbial-based therapeutics such as probiotics, prebiotics, symbiotic or fecal microbiota transplantation have shown promising effect in improving host metabolic health (15, 16). Prebiotics consumption changes the composition of gut microbiota, alters levels of satietogenic gut peptides, decreases systemic inflammation, and improves insulin sensitivity and glucose tolerance (17). Supplementation of probiotics in overweight and obese individuals with probiotics reduces body weight and obesity indices (16, 18, 19). The use of probiotics also reduces intrahepatic triglyceride (IHTG) in patients with non-alcoholic steatohepatitis (20) and improves post-prandial glucose control in subjects with type 2 diabetes (21). G-NiiB®, a patent-protected microbiome immunity formula, composed of naturally occurring food-grade bacteria approved by health authorities, has been developed by a group of CUHK gastroenterology experts.