The microbiome and the gut have attracted a lot of interest over the past few years for their connection with everything from digestion, to immunity to cancer.
The microbiomes of infants are particularly intriguing to researchers—they’re dynamic and flexible, and their composition sets a key foundation for healthy development. Antibiotics and more C-sections in countries like the United States, though, have shifted the types of bacteria doctors most commonly see in the infant microbiome, which could have implications for overall health.
“From 15 plus years of research, we’ve identified that babies in industrialized nations no longer have high levels of bifidobacteria,” Bethany Henrick, director of Immunology & Diagnostics at Evolve Biosystems, told The Daily Beast.
That’s a problem, she said, because high levels of bifidobacteria in infants are associated with lower rates of obesity and asthma later in life. The bacteria likely play an important role in healthy gut function and helping the immune system develop.
“[Bifidobacteria] is important for a healthy microbiome,” she added, particularly because it’s associated with a lower risk of autoimmune and allergic diseases. “It’s safe to say that having a proper microbiome can be important for proper immune development.”
Evolve Biosystems, based in California, has developed a prototype screening test that can identify if an infant has low levels of bifidobacteria. “The test is meant to give clinicians tools to identify which infants need more bifidobacteria,” Henrick said.
The Evolve test is based on the pH levels in baby’s stool, which correlates with levels of bifidobacteria. “We were able to develop, in quite short order, an instant point of care test that specifically points out whether an infant has low levels of this bacteria or high levels,” Henrick said.
The test is currently undergoing user testing in medical clinics across the country. “We chose areas that specifically gave us the widest demographic population,” Henrick said. They’ll use the results of those user tests in an application for approval of the test from the Food and Drug Administration.
Evolve also produces and sells a probiotic that contains a subspecies of bifidobacteria, called bifidobacteria infantis, which Henrick says is a particularly important member of the bifidobacteria family. Unlike some other members of the bifidobacteria family, B. infantis consumes the entirety of a human milk sugar—other types of the bacteria cut the complex milk sugar into bits, consuming it in pieces.
“The sugar becomes simple sugars, and pathogenic bacteria like simple sugars,” Henrick said. “Then a cross-feeding happens. B. infantis takes it all and digests it completely.”
The probiotic, called Evivo, (which costs $70 for a one-month supply) is safe and well-tolerated by infants, according to a clinical trial funded by Evolve. Breastfed infants who were given the probiotic from day seven through day 28 of life had higher levels of bifidobacteria, overall, and the levels remained elevated for a month after they stopped taking the supplement, according to a study conducted with Evolve.
That’s different from many probiotics, which research often finds only change the microbiome as long as they’re being continuously taken. Because Evivo leads to significantly higher bifidobacteria totals, it can supplement babies that the test says have a low level of those bacteria, Henrick said.
Anne Hoen, assistant professor of epidemiology at the Geisel School of Medicine at Dartmouth, told The Daily Beast that the work done with Evivo is compelling, but cautions that the illnesses linked to abnormal microbiota are complex. Although there’s a connection between higher levels of bifidobacteria and a lower risk for some illnesses, we still don’t know that introducing that bacteria through a probiotic to an infant would be entirely preventative.
“Having more bifidobacteria in your stool as an infant might decrease your risk, but it doesn’t eliminate it. Not having the bacterium doesn’t make it a sure thing that you’re going to get the disease,” she said.
Supplementing with a probiotic isn’t likely to be harmful, Hoen said, but the value hasn’t been entirely proven: Taking a probiotic has been shown to increase levels of bifidobacteria, but it hasn’t been shown to actively protect against disease.
“But this is a first step, and it’s great,” she said. “I applaud this group for making this stuff available.” At this point, probiotics are a bit of a blunt instrument, but in the future, she expects we’ll see stronger evidence that they actually do improve health. “I believe it’ll happen, but it’s not clear just yet. There’s still work to do.”