These ‘clinically tested’ gummies may or may not help you poop

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Influencer after influencer says the same thing about Grüns. The gummy vitamins are delightful, chockful of whole organic ingredients, and much tastier than icky powders or pills. One of my most indelible childhood memories is the chalky, gritty, vaguely fruit-flavored taste of a Flintstones vitamin. I hated those cursed tablets so much, I learned how to swallow pills to avoid having to chew them. So I get the whole gummy supplement trend. Squishy, sweet, and infinitely more fun to eat, who wouldn’t want vitamins in a candied form?

If a gummy bear married a green smoothie, you’d get a pack of Grüns. Chewable vitamins aren’t new, but Grüns’ success is thanks in part to its aggressive messaging on social media. I couldn’t help but notice the same buzzwords and phrases popping up over and over. “My kids love these.” “These taste way better than greens powders.” “Free from allergens, sugar-free, vegan, and 100 percent of your daily needs.” The most egregious were two influencers who each started their video saying, “Just because you get something for free doesn’t mean you have to give a good review.” Both proceeded to give the Grüns gummies good reviews, cycling through some of the familiar talking points. Recently, I’ve also seen ads for Grüns targeting GLP-1 users, claiming the gummies are “Ozempic’s new bestie,” as one pack daily will help you poop better.

It’s easy to tell when an influencer is parroting a prewritten spiel for a brand deal. But see an ad enough times, and inevitably, a percentage of people will get curious. Again, does anyone really love the taste of green powder juices? What tired parent hasn’t worried about their picky child getting enough nutrients? I know no one jumps out of bed in the morning with a pep in their step to take a Centrum multivitamin. Throw in some cute packaging and science-washing, and welcome, friend, to the wellness Wild West.

A few weeks ago, I asked Optimizer readers which popular wellness brands they’d like me to look into. Grüns was one of them. Moseying on over to the company’s site, it was also one of the few with a science marketing page. I was prepared for the usual science-washing tropes. Words like “clinically” or “scientifically backed.” Dubious graphs. Celebrity endorsements. A sprinkling of science-y words here and there to give a veneer of legitimacy. Check, check, double check.

There’s a lot that I could nitpick about Grüns. For starters, experts have noted that gummy vitamins are often less effective than tablets or powders for a variety of reasons, including perishability. I could also get into how it uses a proprietary blend, meaning you don’t actually know how much of each organic, whole food ingredient is in the product. Or the fact that its top two ingredients are soluble fiber, leaving out insoluble forms. Not to mention, experts have long cautioned that while supplements like greens products — be they powdered or gummies — can help, they’re not magic substitutes for eating vegetables. But for this exercise, I’m going to zero in on whether Grüns’ clinical testing actually proves any of its marketing claims.

Grüns’ science page has the word “clinically-tested” right up top. The lead image is a green gummy bear sitting in a petri dish — it’s highly reminiscent of the marketing on the science page for AG1, another viral greens powder product. Scroll down, and you’ll see a green bear mascot called Dr. Barry holding a clipboard next to words like “12 weeks,” “placebo-controlled,” “double-blind,” and “randomized.” There’s a paragraph explaining that Grüns ran blood tests to see whether folate and vitamin C levels increased in participants. (Unsurprisingly, the graphs say the gummies did.) You have to squint at a footnote to see that the clinical study involved 120 healthy adults aged 23 to 59.

But nowhere is there a link to the actual study. Based on Grüns’ site alone, you’d have to just take their word for it.

This is likely because this clinical study wasn’t peer-reviewed or published in a journal. That’s not inherently a crime. Peer-review is an expensive process, and technically, it can be overkill for smaller companies in the wellness space. Supplements aren’t regulated, and therefore, this kind of testing isn’t required. Even so, brands that do partake in any kind of research are usually keen to publicly link to any sort of “proof,” be it an internal white paper or citations to external studies that back up claims.

Voluntarily testing products adds an air of legitimacy, but Grüns’ lack of source material is a bit of a red flag. Especially since further down on the page, Grüns has no problem linking to third-party testing certificates for pesticides, heavy metals, and other contaminants.

Some internet sleuthing led me to Citruslabs, which ran the clinical study. It, too, had a page describing the Grüns study, in slightly more detail. Emphasis on slightly.

On the one hand, you can see four bullet points that sort of clarify the study’s design and methodology. There’s a sentence that mentions that “the trial adhered to rigorous scientific standards.” As for the results, six bullet points say things like “significant increases” in folate compared to placebo, “improved biomarkers,” and “clinically shown to boost Vitamin C levels.” Nowhere is there a mention of the gummies helping study participants poop better. At the end of the page, there are three sentences about the benefits of clinical research and how Grüns “demonstrates transparency, scientific rigor, and a true commitment to consumer health” for having used Citruslabs’ services.

I’m not saying this clinical study doesn’t exist, or that the research wasn’t done. But the presentation leaves much to be desired. The generous read is that Grüns and Citruslabs have opted to make the study digestible. However, the reality is you’re being asked to take Citruslabs and Grüns’ word that they haven’t used marketing spin to exaggerate results. Case in point, AG1 also made claims about significant increases in certain biomarkers on its marketing page. When I reviewed the AG1 study’s data, it was a reminder that “significant” can be an incredibly subjective word.

I couldn’t do that with this Grüns study. I reached out to the company to ask why it chose to present the study’s results in this way, but haven’t gotten a response.

To me, the most interesting thing here is how clinical testing has not only become a marketing tactic, but a product in and of itself.

Citruslabs, for example, is a contract research organization (CRO). Medical tech and pharmaceutical companies use them to outsource some aspects of clinical testing, often with the goal of reducing cost. The company’s site markets itself as a one-stop shop for consumer health brands that might want clinical research to back up their brands. That means everything from crafting study design and recruiting participants to securing ethical board review if applicable. It counts several well-known brands and companies among its client list across the wellness and cosmetics industries, including Blume, Mario Badescu, Hum, and Green Chef.

Critically, clinical studies are not the only thing the company provides. They also conduct consumer perception studies. As in, consumers are asked to give their self-reported opinion of a product after using it. You can usually tell the difference in wording. In perception studies, you often see phrases like “80 percent of users said X condition improved after using Y product for Z weeks.” Self-reported data like this has many limitations, not least of which are bias and misremembered information. But, perusing Citruslabs’ client list, it’s very easy to assume every brand on there is doing rigorous scientific research on its products, when many are just getting a form of consumer feedback for marketing purposes.

Blurring the lines between these two types of studies can lead to some confusion. Let’s go back to Grüns’ science page. Underneath its clinical study results, it lists statistics like “67 percent say their overall health and well-being have improved” while “44 percent report clearer thinking and better focus.” The survey claims 67 percent have reported “better, more regular digestion” but that could mean anything from less bloating to more pooping. Crucially, that data is not from its clinical study — it’s from a post-purchase consumer survey of 3,000 customers. While that’s disclosed in a footnote on the site, it’s not hard to see how laypeople might conflate the two types of “evidence.”

Perusing LinkedIn, I saw a post from Grüns CEO Chad Janis deriding skeptics. “‘Gummy vitamins don’t work.’ (Spoiler: Grüns did a clinical study. The results are good.)” Janis goes on to paint criticisms of gummy vitamins as a “convenient myth” spread by pill and powder companies, and then launches into the consumer survey results. He’s using the wellness grifter playbook by saying: Science says it works, you can’t trust what the supplement establishment says about them, and here’s anecdotal proof to further validate their position.

I can understand why wellness companies are turning to “clinical research” and CROs like Citruslabs. There’s a lot of snake oil in the unregulated supplement market. In essence, this is an attempt to stand out and earn consumer trust by “doing the science.” But that’s undermined when scientific and consumer studies are blurred together. Grüns’ clinical study only proves that compared to no vitamin supplementation, eating Grüns gummies will increase folate and vitamin C levels. It says nothing about how the gummies compare to greens powders or traditional multivitamins. Frankly, one would expect that taking a supplement increases certain nutrient levels. What consumers likely want to know is how the gummies compare to the products Grüns wants to replace. Based on the ads, GLP-1 users might want to know if these gummies will help with constipation. It might, or it might not. While 6g of fiber is a significant amount for a single product, that’s not a guarantee you’ll poop more efficiently. You might! You might also end up with gastrointestinal distress, depending on your current hydration and diet.

The problem with this study is that it doesn’t answer these questions at all.

My deep dive into Grüns wouldn’t be complete without trying the gummies. Especially since influencer after influencer raved about the taste, while several commenters called bullshit, noting the gummies were more akin to crumbly, grass pellets. One “honest” review I saw featured a woman gagging after trying a few. Online, hyperbole runs in both directions.

My verdict: It’s generous to call Grüns gummy bears. Opening a packet, I was overwhelmed with a chemical-like smell. The gummies themselves are strangely firm, with a slight sandy grit when you bite into them and an odd, grassy aftertaste. They’re not horrible, but they’re more like compact bits of fruit leather than a gummy bear. Texturally, it’s a no for me. Would I choose them over the Flintstone vitamins of my youth? Honestly, I’d rather swallow a pill. Without a clear win on taste, the rest of Grüns’ pitch rings even more hollow.

All-in-all, this was another excursion into the wellness Wild West that underscored how “clinically backed” is losing any sort of meaning. Instead, clinical testing is starting to feel like a side hustle of its own. A way for companies to imply trustworthiness, while actually skirting the actual questions consumers want answered.