Consuming Your Own Fecal Microbiome When Dieting May Help Limit Weight Regain, According to Israeli Researchers.
People who consume frozen microbiome capsules derived from their own feces when dieting may limit their weight regain, according to a new study published in Gastroenterology, in a collaboration led by Israeli researchers.
In an unprecedented 14-month clinical trial in Israel, Prof. Iris Shai; then-BGU Ph.D. student Dr. Ehud Rinott and Dr. Ilan Youngster, collaborated with a group of international experts from U.S. and European research institutes.
“It is well known that most dieters reach their lowest body weight after 4-6 months and are then challenged by the plateau or regain phase, despite continued dieting,” says Prof. Shai, a member of BGU’s School of Public Health. “In this groundbreaking study, our international group of researchers explored whether preserving the optimized personal microbiome from fecal transplants after six months helps maintain weight loss by transplanting back the optimized microbiome during the subsequent regain phase.”
In the weight loss trial, abdominally obese or dyslipidemic (high cholesterol) participants in Israel were randomly assigned to one of three groups: healthy dietary guidelines, a Mediterranean diet, and a green-Mediterranean diet. After six months during the weight-loss phase, 90 eligible participants provided a fecal sample that was processed into an autologous fecal microbiota transplantation (aFMT) by frozen, opaque and odorless capsules. The participants were then randomly assigned to two groups that received 100 capsules containing their own fecal microbiota or a placebo, which they ingested until month 14.
In the green-Mediterranean diet group, participants were provided with Mankai, a specific duckweed aquatic strain in a green shake, green tea and 28g. of walnuts. This was the only group diet strategy that induced a significant change in the gut microbiome composition during the weight loss phase.
The 90 participants lost 8.3 kg (18.2 lbs.) on average after six months. However, only in the green-Mediterranean diet group did aFMT limit weight regain to 17.1%, versus 50% for the placebo.
“The green-Mediterranean diet also resulted in preservation of weight loss-associated specific bacteria and microbial metabolic pathways, mainly glucose transport, following the microbiome intervention, compared to the control,” says Dr. Rinott.
“This study is the first of its kind to prove in humans that preservation of an “ideal” gut microbial composition can be used at a later point in time to achieve metabolic benefits,” says Dr. Youngster, director of the Pediatric Infectious Diseases Unit and the Center for Microbiome Research at Shamir Medical Center. “Using the patient’s own stool after optimization is a novel concept that overcomes many of these barriers. It is my belief that the use of autologous fecal microbiota transplantation will be applicable in the future for other indications as well.“
Furthermore, a green plant-based diet such as Mankai, better optimizes the microbiome for the microbiota transplantation procedure. This potentially optimizes the conditions for the aFMT, collected during the maximal weight loss phase.
In a complementary Mankai-specific mouse model experiment conducted by Prof. Omry Koren at Bar-Ilan University, the researchers were able to reproduce the effects of aFMT on regain and insulin sensitivity, and to isolate specifically how Mankai induces these effects. The Mankai duckweed aquatic plant is being grown in Israel and other countries in a closed environment and is highly environmentally sustainable – requiring a fraction of the amount of water to produce each gram of protein compared to soy, kale or spinach.
According to Prof. Koren, “The nutrition-microbiome axis has been proven in this study, as high polyphenols diet, and specifically, Mankai, a protein-based plant and dietary fibers could ideally optimize the microbiome in the weight loss phase. It induces the potent microbiome to recall the flora of germs related to regain attenuation and improved glycemic state after transplantation.”
“These findings might be a good application of personal medicine,” says Prof. Shai, who is also an adjunct professor at Harvard University. “Freezing a personal microbiome bank could be an effective way to maintain healthy weight while dieting, since the rapid weight loss phase is accompanied by optimal cardiometabolic health. By optimizing the composition and function of the gut microbiome within the host, we have a novel approach for metabolic-memory preservation.”