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Have You Taken Your Synbiotics Today?

Healthy supplements on wooden teaspoons against pastel blue background

Our microbiomes are turning out to be pretty essential health factories. Having the right bacteria in our digestive tract has been linked to everything from regulating our moods to fighting cancer. Now, new supplements promise to help improve our gut health—if they’re not made by charlatans.

These promising biome boosters are called synbiotics, and they combine prebiotics—the fiber that feeds beneficial gut bacteria—with probiotics, the beneficial bacteria themselves.

Defining Moment

First conceived in 1995, along with the definition of prebiotics, “synbiotics” has been a fairly broad term in a category of supplements that is only loosely regulated by the FDA. To try to bring some consistency to the term, the market, and research efforts, a group of experts known as The International Scientific Association for Probiotics and Prebiotics, solidified a definition of the term and set forth guidelines for the development and investigation of synbiotic supplements.

The new definition reads as follows: “A mixture comprising live microorganisms and substrate(s) selectively utilized by host microorganisms that confers a health benefit on the host.”

The key here is the relationship between pre- and probiotics. One must enhance the other, instead of manufacturers just throwing any combination into a supplement and calling it a synbiotic.

“In synergistic synbiotics, the substrate would support probiotic survival,” says Hannah Holscher, panel member and assistant professor in the Department of Food Science and Human Nutrition at the University of Illinois (UI). “For example, providing an energy source for the probiotic or changing the microbiome to support the survival of the probiotic.”

Buyer Beware

The members of the panel, which was chaired by UI’s Kelly Swanson, expect that cleaning up the confusion around synbiotics will help the market begin to grow. They also point out that before taking a synbiotic, it’s a good idea to consult with an expert to see precisely which combination of pre- and probiotic you need

“Just because there’s a pre-, pro-, or synbiotic on the market, that doesn’t mean they’ll work across the board from infants to adults to geriatrics, from heart disease to gastrointestinal health. They’re all really there for a specific purpose,” Swanson said.

Holscher adds: “The question is not whether you should take a pre-, pro-, or synbiotic. The question is, ‘what do you need those products to do?’ We know a lot about the specific health outcomes of these products, so it’s a matter of finding what you need rather than thinking of them as a blanket cure-all.”

The paper that lays out the new synbiotic criteria and definition has been published in the peer-reviewed journal, Nature Reviews: Gastroenterology & Hepatology.