Do ‘gut sodas’ really offer health benefits?

Depending on where you shop and in which aisle, you may have noticed the colorful packaging of “gut sodas” taking up shelf space.

These sodas may contain probiotics or prebiotics and they may or may not contain sugar or sugar substitutes. But as the newest category of “functional beverages,” they do seem to suggest that they will help your digestive system.

Recently, big players like Coca-Cola and PepsiCo have gotten into the game, as well as celebrity investors Gwyneth Paltrow, Mindy Kaling and the Jonas Brothers.

“Fizzy, fruity, tangy, spicy, gutsy,” proclaims the wording on a can of Culture Pop.

“Trust your gut!” Cove Soda says.

“Soda’s back,” the Poppi can says, implicitly acknowledging that we all know the empty calories of the previous generation of sugared sodas are not good for you.

Deciphering the label

Your digestive system contains trillions of microorganisms — the gut microbiome. Maintaining a healthy gut is important for overall health via factors like facilitating proper digestion and maintaining metabolism and immunity, according to the American Medical Association.

If you’re interested enough in your health to be curious about gut sodas, presumably you’d want to know what’s in them and how they work.

But as the three brands I tried demonstrated, figuring that out is not so easy. They all have different stuff in them, so you must be able to read and comprehend the small type.

An advanced degree in biology would not be amiss — and a pair of reading glasses.

For help, I turned to Paige Langhals-Totino, a nutrition specialist who works in Allegheny Health Network’s gastroenterology division. She also sees patients who are interested in weight management.

First of all, what’s the difference between prebiotics and probiotics?

“Probiotics are usually live microorganisms that are meant to rebuild the healthy gut bacteria,” she said.

They may come in capsules, powders, liquids and in drinks such as kombucha.

What about those 1 billion CFUs (colony-forming units) in Cove Soda? That’s a lot, right?

“It sounds like a lot,” Langhals-Totino agreed.

The theory goes that the more CFUs there are, the more likely it is that some of those beneficial organisms will survive your stomach acid and do some good in your gut, she said. The problem is, we do not know how many organisms will guarantee that benefit.

“You could take 1 billion versus 5 billion and still have the same outcome,” she said.

Prebiotics, on the other hand, are fiber alternatives or fiber-based products, Langhals-Totino said. “It’s a food source that is meant to fuel the good bacteria that is already in the GI tract.”

Do they help?

It all sounds very scientific, but is there evidence that drinking a soda or taking a supplement actually has a health benefit?

Langhals-Totino said, for both prebiotic and probiotic supplements, “we have very much mixed data.”

The prebiotic soda Poppi ran into trouble with its exhortation to “Be Gut Happy. Be Gut Healthy.” The company, which was acquired by PepsiCo this month, faced a class-action lawsuit for false health claims. It settled for $8.9 million.

There are studies that say prebiotics and probiotics are helpful, but others that show no benefit.

In the case of prebiotics, there is also evidence that promoting only one strain of beneficial bacteria — as these sodas may do — can in fact create an imbalance in the multitude of species in your gut if consumed over a long period of time, according to the academic medical center Henry Ford Health.

If there is an existing imbalance, it is difficult to know which strain may be of most benefit to you.

Langhals-Totino takes a case-by-case approach.

“Usually what I counsel my patients is, how do they feel when they’re taking it?” she said. “There’s no harm in doing a probiotic or doing a prebiotic that is not causing them new symptoms or worsening of any GI symptoms they already have.”

She said prebiotics, like fiber in general, can lead to bloating and discomfort. Carbonation in the soda may have the same effect. Particularly for patients with irritable bowel syndrome, she recommends caution.

“They’re the ones who are going to be at highest risk to see the side effects of bloating, increased gas production, nausea and discomfort,” she said of IBS patients.

Then there’s the question of sugar substitutes, which some studies paradoxically suggest may actually lead to weight gain, rather than loss. Some have also been linked to a reduction in the diversity of the microbiome.

The takeaway

Rather than for any gut-health benefit, Langhals-Totino is more likely to recommend these sodas to patients who are trying to lose weight, as a substitute for sugary sodas.

“If the patient likes it, if they’re seeing a benefit, I encourage them to continue it as a step to stay away from regular soda,” she said. But she wouldn’t “prescribe” them.

For digestive health, she suggests fermented foods like kombucha, sauerkraut or kimchi. For a hit of both probiotics and prebiotics, she recommends a low-sugar yogurt with live cultures mixed with berries or other fruit.