The Role of Microbiome in Recurrent Obesity

This past century witnessed a significant increase in the prevalence of obesity, when since 1980 worldwide obesity has more than doubled. According to the World Health Organization, 39% of adults from the age of 18 years or older are overweight while 13% are obese. Successful maintenance of weight loss as losing at least 10% of the initial body weight and maintaining it for at least one year. However, keeping the low body weight is rarely maintained, as 80% of people who lost 10% of their body weight will return to their initial weight within a year. When weight loss is maintained for 2-5 years the chance of long term success was shown to dramatically increase. Although there is no agreement as to what contributes to the recurrent weight regain phenomenon (also known as \'weight cycling\' or \'yo-yo diet\'), it is strongly associated with the risk of developing metabolic risk factors and their complications including heart disease and all-cause mortality. Altering the gut microbiota is one method to treat disease states associated with gut bacteria. For instance, fecal microbiota transplant (FMT) or fecal bacteriotherapy, is the process of transferring stool from a healthy donor to another. The goal of FMT is to restore host health by increasing diversity and function of the gut microbiota. The main advantage of FMT over probiotics is its ability to transplant the entire gut microbiota and metabolites from the donor to the recipient. Although numerous individual microbes have been identified as related to obesity, multiple studies suggest that loss of microbial diversity has a stronger impact on the development of metabolic dysfunction, this diversity may be restored by FMT. This study will determine whether microbiome modulation might be a possible future target against recurrent obesity in humans, and whether orally administered FMT from a lean donor, post weight loss might be an effective intervention to prevent weight regain.