Prebiotic Drinks: What Are They, and Should You Be Drinking Them?

If you pop the top on a regular soda, you likely don’t expect it to deliver health benefits. But a newer class of drinks, calling itself prebiotic sodas, is presenting itself as a healthier alternative to the standard fizzy drinks that fill our fridges.

But a lawsuit filed in San Francisco on June 5 alleges that Poppi, a line of prebiotic sodas, falsely claims gut health benefits that consuming a single can doesn’t actually deliver. Poppi, founded in Texas in 2015, became popular after an appearance on the show Shark Tank. 

The lawsuit, which seeks class action status, alleges that Poppi is falsely claiming that its sodas are “gut healthy” from added dietary fiber. Each can of Poppi has two grams of fiber, which isn’t enough to receive a meaningful benefit, the lawsuit says. Poppi also contains cane sugar, which the suit argues would offset the benefits of fiber if someone consumes enough.

“We are proud of the Poppi brand and stand behind our products,” a spokesperson for Poppi’s parent company VNGR Beverage told CBS MoneyWatch in response to the filing. “We believe the lawsuit is baseless, and we will vigorously defend against these allegations.”

A representative for Poppi didn’t immediately respond to a request for comment.

The lawsuit calls attention to prebiotic drinks, which are different from the more popular category of probiotic drinks such as kombucha. Prebiotic drinks are carbonated, flavored drinks that many people see as a healthier alternative to regular soda. Poppi and Ollipop are among the popular prebiotic soda brands.

Here’s what you need to know about prebiotic sodas and whether they actually deliver health benefits.

Read more: Gut Health Matters: Why You’re Bloated and Ways to Restore Gut Balance

What are prebiotics?

According to the National Institutes of Health, prebiotics were first defined in 1995, but that original definition has been questioned and a new consensus has yet to be reached.

“Prebiotics are generally dietary fiber — non-digestible carbohydrates — that get fermented in the gut, change the microbiota and have a health benefit,” said Joanne Slavin, a registered dietician nutritionist and professor at the University of Minnesota.

Poppi, the line of prebiotic drinks that is facing the lawsuit, contains prebiotics in the form of agave inulin, plus apple cider vinegar, cane sugar, stevia and fruit juice.

Prebiotics differ from probiotics

Although the names are similar, prebiotic drinks aren’t the same as probiotic drinks, like kombucha, a drink produced by fermenting sweet tea with a live culture of yeast and bacteria. Most of what shoppers see on grocery shelves are probiotics. 

“Most prebiotics are dietary fibers,” Slavin said. “Probiotics are microbes in foods, so fermented foods such as yogurt and sauerkraut would be considered probiotics. Both prebiotics and probiotics can be consumed in foods, drinks or dietary supplements.”

Read more: Want a Healthier Gut? 12 Probiotic Foods to Add to Your Diet

And the dietary fiber in the drinks could be a boon for some Americans. Fiber recommendations in the US are 28 grams per day per adult, according to the USDA, and most Americans aren’t consuming nearly that much.

“Most fiber-containing foods contain between 1 and 3 grams of fiber per serving,” Slavin said. “Whole grains, vegetables, fruits, legumes, nuts, seeds are all fiber sources. Most of us only consume 15 grams of fiber per day, so strategies to increase dietary fiber intake are of interest.”

Read more: Best Probiotic Supplements for Gut Health

The whole tooth

Dr. Zev Schulhof from Iconic Implants told CNET’s Michelle Honeyager that Poppi contains apple cider vinegar, which is highly acidic and bad for tooth enamel, although it’s also said to have numerous benefits. He recommends drinking Poppi and other sodas with a straw and brushing your teeth or rinsing with water or mouthwash afterward.

“Most sodas aren’t great for your dental health,” Schulhof said. “Their high acidity and sugar levels can wreak havoc on your teeth enamel, leading to erosion and decay.”

“Despite the grim news above, the actual probiotics and prebiotics within the drinks can be helpful for oral health,” general dentist Dr. David Chen told Honeyager. “There has been some research indicating that taking probiotics can potentially improve periodontal health.”

Dairy can help neutralize acids in prebiotic sodas, according to the American Dental Association, which recommends drinking milk or eating cheese after consuming one.

Read more: Is Your Favorite Prebiotic Soda Ruining Your Teeth? Experts Weigh In

Other health concerns

Inulin, the fiber used in prebiotic sodas, can create digestive distress if consumed in high doses. The lawsuit filed against Poppi claims that consuming too much inulin can lead to “adverse health results” for the liver, abdomen and digestive system.

“Too much inulin can cause digestive issues in some consumers, but usually in larger doses,” Slavin said. “In our work, most consumers are fine with 5 grams or 10 grams of inulin added to orange juice with their breakfast. But we always recommend a variety of fibers in [their] diet. Consumers can also consume fibers as dietary supplements and OTC laxatives that work better in their schedule.

“The existing research finds that very high doses of inulin — 40 grams — may cause diarrhea in some subjects, but others have no issues with inulin,” Slavin said. “I have spent my entire career trying to increase fiber consumption, so as a dietitian I will never give up on increasing consumption of high fiber foods, but also accept that many consumers will choose OTC fiber or fiber added to soft drinks or snack foods.”

No drink can dethrone water

The prebiotic drinks are colorful and trendy, but they’re not a necessity for everyone.

“My general advice is to read the label and decide if you want to add dietary fiber in a beverage,” Slavin said. “If you already get enough fiber in your diet, then maybe a beverage with added fiber isn’t a good choice for you. You should also be aware of the other ingredients in the product — added sugars, alternative sweeteners, for example.”

But there’s another old-school beverage that shouldn’t be forgotten.

“Of course, water is always our top choice as a fluid replacement,” Slavin said.