Why better-for-you gummy worm brand Rotten reformulated its product for retail.

To bring new shoppers into the better-for-you candy category, Rotten used customer feedback and a sampling campaign to totally revamp its product.


A new better-for-you gummy worm is entering retail with the promise of tasting just like the gummy sweets many of us remember from childhood — only with 60% less sugar.

To deliver on this promise, Rotten made the radical decision to completely overhaul its product, from taste and texture to even the packaging, in the four months running up to this retail debut.

The Rotten gummy worms now available at Foxtrot, Zumiez, Pop Up Grocer and other retail locations across the US are the “2.0” version, says founder Michael Fisher.

As of today, Thingtesting users can also buy one, get one free at participating stores in exchange for honest feedback on the product.

“People eat candy purely because it tastes delicious — not [for] nutrition,” says Fisher. “If you don’t deliver on that, people are just going to return to the bad-for-you options.”

Reformulating using customer feedback

Before launching in retail, Rotten sampled its product with backers of its Kickstarter campaign, as well as social media followers and Thingtesting users. “We had rich data about the improvements they were looking for, whether it was shared in reviews, in-person sampling, or to our customer service inbox,” says Fisher.

Patterns quickly emerged from these 300-plus early testers: people wanted stronger flavors in general, while the mango gummy worm was proving divisive. When Rotten made its product available for wider purchase in September 2023, even more feedback rolled in, as well as a new kind of customer — the gummy worm fanatic.

This group, Fisher says, wanted the health benefits but weren’t willing to compromise on taste and texture. In response, Rotten dialed up the amount of gelatin in its recipes (to create a more classic gummy texture) and also amped up the flavors of its original and sour worms.

New flavors like cherry and lime were also added, while mango was nixed.

“It wasn’t that our product before was bad and this one is good,” Fisher says. “It’s just we’re attracting a customer who’s a huge fan of the gummy worm anyway. We need to serve that group very well, because they’re the strongest buyers.”

Convincing customers on better-for-you

Better-for-you candy isn’t new, but the idea is yet to go mainstream. With 61% of Americans wanting to limit sugar intake, Fisher argues there is clearly a “broad range of people who want these products.”

The thesis seems to be correct, and Fisher says 70% of Rotten’s customers are people who have never purchased better-for-you candy before. This is a “compelling metric” for retailers, Fisher says, as it shows “we’re bringing new people into this premium subcategory.” Through Thingtesting’s Try New Things program, the brand will also gain further insights on how the product is performing in store.

But as well as convincing new shoppers to try — and stick with — low-sugar gummy worms, Rotten is wondering if it can win back early customers who tried the worms but didn’t like them.

Rotten has already started sending complimentary packs of its new recipe gummies to people who previously left negative reviews. A study by market research agency Hot Cow found that 63% of consumers said they would buy a product if a free sample changed their perspective on the brand.

The feedback has been “exceptional” so far Fisher says, with some comments suggesting Rotten may even have achieved the holy grail for a better-for-you brand: “These don’t taste like low-calorie gummies,” said one review Fisher shared with Thingtesting. “They taste better than the old school brands that use way more sugar."