The manufacturers of Poppi soda are being sued over claims that its drinks do not contain enough prebiotic fiber to "cause meaningful gut health benefits for the consumer from just one can."

VNGR Beverage LLC, the Texas-based corporation that manufactures, markets and sells Poppi sodas, is named in the class action lawsuit filed by San Francisco, California woman Kristin Cobbs. The complaint alleges Poppi sodas only contain two grams of prebiotic fiber, which means "a consumer would need to drink more than four Poppi sodas in a day to realize any potential health benefits."

"However, even if a consumer were to do this, Poppi’s high sugar content would offset most, if not all, of these purported gut health benefits," according to the suit filed in the Northern District of California.

Drinking enough Poppi to "promote gut health" would cause consumers to drink "harmful levels of cane sugar," which the soda is primarily made of, the complaint alleges. Too much cane sugar has been shown to harm gut health, the legal filing continues.

"Despite Poppi’s 'prebiotic' marketing claims, which assure consumers, on the can, that they can 'Be Gut Happy (and) Be Gut Healthy,' as one nutritionist bluntly explained: the products 'are basically sugared water,'" according to the complaint.

Poppi addressed the suit in a statement emailed Monday to USA TODAY.

"We are proud of the Poppi brand and stand behind our products. We are on a mission to revolutionize soda for the next generation of soda drinkers, and we have diligently innovated to provide a tasting experience that millions of people have come to enjoy," the statement said. "We believe the lawsuit is baseless, and we will vigorously defend against these allegations."

What is Poppi soda?

According to Poppi's website, Poppi drinks combine agave inulin, apple cider vinegar and fruit juice into a soda that's 25 calories or less, contains 5 grams of sugar or less and contains prebiotics.

The website notes that the agave inulin is a prebiotic and natural sweetener extracted from the agave tequilana plant.

"Inulin is a prebiotic fiber that may support gut health by diversifying the gut microbiome and providing fuel for good bacteria, particularly Bifidobacteria and Lactobacilli," the website adds.

Poppi's founders, Allison and Stephen Ellsworth, featured their drink on ABC's "Shark Tank," which led to the sodas being placed on the shelves of Whole Foods Market stores.

According the the complaint, Poppi's sales topped $100 million as of 2024, and those numbers continue to grow as the drink represents 19% of the U.S. market share, surpassing Coke but 1.5 times.

"With the help of an investment on Shark Tank, Poppi has gone from farmers'-market-favorite to sitting pretty on the shelves of every major retailer across the nation," the company's website says, while noting that the sodas are "beloved" by stars like Post Malone, Hailey Bieber, Kylie Jenner, Billie Eilish, Russell Westbrook, Jennifer Lopez and Olivia Munn.

Cobbs would not have bought Poppi if she knew the soda 'could negatively impact her health'

Cobbs last purchased Poppi sodas in March 2024, and based on the drinks' labeling, her understanding was that the products contained "prebiotics" that would make her "gut healthy," the complaint says. If Cobbs knew about Poppi soda's actual prebiotic fiber content, and how the excessive consumption of the product "could negatively impact her health," then she would not have bought the drinks, according to the legal document.

Poppi sodas' inclusion of agave inulin, a type of naturally soluble fiber that when extracted from the agave plant functions as a prebiotic, is mentioned in the complaint. Consuming too much inulin can cause "adverse health results," including a build-up of gas, abdominal discomfort, diarrhea, and liver damage, according to the suit.

Cobbs, who is suing individually and on behalf of others who bought Poppi sodas under the same assumptions she had, is seeking "restitution and all other forms of equitable monetary relief," according to the complaint.