A study led by Seattle’s Institute for Systems Biology suggests that the composition of the bacteria in the gut may influence an individual’s ability to lose weight.
The results are “rather preliminary” according to the report, published today in the journal mSystems. But the findings, examining gut bacteria in people prior to starting a wellness program, could lead to new ways to predict weight loss.
“If I knew what your microbiome looked like, I could tell you whether you would be likely to respond moderate lifestyle intervention,” Sean Gibbons, an assistant professor at ISB who led the study, told GeekWire in an interview. The findings could potentially also lead to ways to enhance weight loss by manipulating the gut microbiome, the collection of bacteria in the intestine.
The study examined the gut microbiomes of people who had taken part in a wellness program as part of the health company Arivale, an ISB spinout that folded in 2019. Participants had sent the company a stool sample as part of a whole-body workup that included blood metabolite and other measures.
The researchers examined the microbiomes of 25 of the participants in deep molecular detail, tallying the types of bacterial genes present in the sample through DNA sequencing. Fifteen of these individuals had lost weight on Arivale’s wellness program, and the rest maintained a stable weight.
The researchers found that people who lost weight had a different gut composition to start with. Their microbiomes were enriched in bacterial genes that divert dietary nutrients towards the microbes and prompt their growth. The bacteria also had faster growth rates, including a bacterial group called Prevotella.
The microbiomes of people who did not lose weight were enriched for bacterial genes that convert fibers into absorbable sugars. Their bacteria also had slower growth rates.
The findings suggest that people who lost weight had a microbiome packed with fast-growing, energy-using bacteria, primed to help them lose weight even before they started their wellness program. Their gut bacteria may be more likely to outcompete the body for energy-rich nutrients, reducing the calorie input to the body.
If the findings hold up in larger studies, they could lead to new ways to predict weight loss by measuring the microbiome.
The findings also fit with previous studies suggesting that Prevotella bacteria are associated with weight loss. And they are part of an emerging scientific picture that the gut microbiome has a major role in health and influences weight.
As new studies emerge, scientists may develop targeted ways to shift the gut composition to a weight-loss ready state, using specific probiotics or other means.
“There may be a way to engineer the microbiome towards a responder state for weight loss,” said Gibbons. “But that’s more in the future.”
He notes that his study stands out because it showed that the microbiome composition associated with weight loss is present independent of starting BMI, body mass index, a measure of obesity and overweight. People who have higher BMIs tend to lose weight faster at first, and their microbiomes can have distinct compositions, which can affect conclusions of microbiome studies.
The new data also showed that gut composition was more strongly related to weight loss than other body measurements, including baseline diet and blood metabolites.
One of the contributing authors, Nathan Price, is now CEO of Onegevity, one of several lifestyle companies that analyze the microbiome, in addition to being an ISB professor.
When asked if Onegevity will use the data for any of its products, Gibbons said, “I can’t say for sure, I know that they are interested in such things. And so something like that could arise.”
Other institutions involved in the study were the Lifestyle Medicine Institute in Redlands, Calif., the University of Washington’s Department of Bioengineering, and eScience Institute, which is focused on data science.
