Gen Z Has a New Favourite Supplement. Nobody Can Agree How to Sell It.

When it comes to wellness in 2026, younger consumers are relying on a gut feeling.

Dietary fibre has been surging in popularity among Gen Z consumers, 62 percent of whom are trying to increase their fibre intake, compared with 36 percent of people over 65, per market research firm Savanta.

The nutrient is expected to overtake protein as the next ubiquitous, “must-have” nutrient in the wellness sphere. Younger people are a strong driver of that growth: The Business of Fashion’s The State of Fashion 2026 report revealed that two-thirds of Gen Z and Millennials purchased functional nutrition products and supplements last year. But the trend’s documented health benefits are undercut by a marketed regression towards thinner beauty standards as some supplement makers underpin their offerings with unsupported claims about fibre’s relationship with GLP-1s and weight loss.

Social media is rich with cautionary tales of young people recently diagnosed with colon cancer (whose early onset diagnoses have nearly doubled in the previous two decades, according to the American Cancer Society) and the accompanying exhortations to pay better attention to one’s digestive health. Such content has given rise to the “fibremaxxing” trend, a movement focused on intentionally upping one’s daily fibre intake through recipes and hacks.

Amid growing supplement scepticism, fibre remains a multi-billion-dollar industry stronghold. Likewise, functional sodas which incorporate prebiotics, probiotics and added fibre have experienced a meteoric rise. PepsiCo acquired prebiotic beverage brand Poppi for $1.95 billion last May, while its independent competitor Olipop was valued at $1.85 billion in a series C funding round last February. (Last Thursday, Olipop released three flavour-inspired lip balms in collaboration with clean skincare brand Cocokind.)

The nutrient’s popularity has only grown following the publication of research on the gut microbiome’s relationship to other areas of the body, including brain function, skin health and weight loss through satiety and GLP-1 stimulation, the last of which has been a point of fixation for fibremaxxers and marketers alike.

The Weight-Loss Marketing Puzzle

In January 2025, Hum Nutrition released a fibre supplement dubbed the “Flatter Me Fiber GLP‑1 Booster,” which purports to “double GLP-1 levels in just one use.” It was the company’s most successful launch to date, having amassed a wait list of 35,000 prospective customers and eventually selling out twice.

Walter Faulstroh, Hum Nutrition’s chief executive, sees two main trends among the supplement’s core customer demographics: those seeking an alternative to GLP-1 drugs and those who seek to maintain their weight loss while and after weaning off GLP-1s.

But not everyone in the supplement industry agrees with Hum Nutrition’s marketing approach. When Dr. Karan Rajan, a UK-based surgeon and content creator, set out to create Loam, the fibre supplement brand he founded last year, he purposefully evaded language that would imply that dietary fibre can boost GLP-1 levels, a claim that he says has been “distorted and overhyped.”

“I see that fibre-GLP-1 headline everywhere,” he said. “It’s not scientifically and physiologically accurate. … I don’t want to clickbait and sensationalise things.”

As Dr. Suzanne Devkota, an associate professor at Cedars-Sinai, Medicine, and director of the Cedars-Sinai Microbiome Research Institute, explained, certain fibres can be fermented by gut bacteria to produce short-chain fatty acids, a compound that can, in theory, stimulate GLP-1 receptors — but with existing literature, the amount one would have to ingest to achieve that effect remains unknown.

“[Fibre is] the one thing we know in the microbiome field that is important for supporting a healthy gut microbiome,” Devkota said. “[But] when people are calling it ‘nature’s Ozempic,’ I think that’s a little bit of an overblowing of what the data actually says.”

Fibremaxxing’s Tricky Politics

Meanwhile, another camp is questioning the overarching ethics of a marketing strategy that assumes weight loss is a universal aspiration — and that body fat is inherently an issue requiring rectification.

For those who subscribe to the body positivity and fat liberation movements, the implicit messaging behind GLP-1-boosting supplements follows an exhausting and painful but unsurprising refrain: It echoes that of many bygone fad dietary plans touting themselves as quick “fixes” to the “problem” of fat bodies before eventually fading into obscurity.

“The desire to suppress your appetite to lose weight is based on the belief that fatness in unhealthy, unattractive, unworthy, and those beliefs are based on anti-fatness,” said Vinny Welsby, founder of the DEI consultancy Weight Inclusive Consulting and host of the “Fierce Fatty” podcast.

Regardless, the fibre trend may be taking permanent hold: Over half of 1,000 US consumers surveyed by data and market research firm Datassential said that they would prioritise consuming more foods and beverages aimed towards improving digestive health this year.

And even though ad campaigns overwrought with lofty claims and industrial jargon aren’t always definitive, many are learning to embrace the fibremaxxing movement — even if the supplement market is starting to feel a touch oversaturated. Experts like Devkota believe that the benefits of people upping their fibre intakes outweigh the dangers of potentially inflated messaging.

“It’s kind of funny to me to call [fibre] a craze … but I do think it’s a good thing,” Devkota said. “Whatever it takes to get people thinking about [fibre] and implementing it into their diet, however it gets done, is great.”

Sign up to The Business of Beauty newsletter, your complimentary, must-read source for the day’s most important beauty and wellness news and analysis.