The age of the “Protein Industrial Complex” is upon is. Hitting protein “macro” targets has become a daily ritual for millions of health-conscious consumers, and brands have taken notice. Protein is embedded into nearly every packaged food category — bagels, pancakes, popcorn, cereal, pasta, milk and even water. Fueled by gym culture, longevity messaging, and more recently the rise of GLP-1 medications that intensify concerns around muscle loss, protein has evolved from a nutrient into a commercial obsession reshaping how consumers think about food and wellness.

But alongside that expansion, another conversation has quietly begun gaining momentum — one centered not on feeding muscle, but the microbiome. Now, startups and wellness brands are repositioning fiber away from a senior citizen’s digestive aid, into a foundational component of metabolic, hormonal, and long-term health. I spoke with Colleen Cutcliffe, Chief Executive at Pendulum Therapeutics on how fiber is rebranding to join protein as a cornerstone of the nutrition stack.

Protein obsession is no longer a fringe gym-culture phenomenon. In January 2026, the U.S. Department of Health and Human Services, unveiled new dietary guidelines urging Americans to prioritize protein at every meal — increasing the recommended daily intake from 0.8 grams per kilogram of body weight to 1.2 to 1.6 grams. Former FDA Commissioner Marty Makary declared when announcing the new guidelines, “for decades we have been fed a corrupt food pyramid that has demonized protein like eggs and steak” and “ignored a giant blind spot – refined carbohydrates, ultra-processed foods….That is an epidemic.” The old guidelines were “to prevent starvation and withering away.” The new ones are “designed for American kids to thrive and they are based on science, not on dogma.”

Beyond a general cultural shift in attitudes away from high carb and processed foods and towards more keto-friendly diets, the protein industrial complex has a few drivers. The mass adoption of GLP-1 medications has created an unanticipated muscle-loss crisis : consumers chemically suppressing their appetites are losing weight, but a disproportionate share of that weight may be coming from lean muscle rather than fat. 1

Women separately face another challenge. Estrogen loss during perimenopause and menopause accelerates the breakdown of bone and muscle mass, putting women at outsized risk for osteoporosis and sarcopenia.

The answer? More protein – and resistance training. Protein provides the essential amino acids needed to repair microscopic tears caused by exercise and build new muscle tissue. This drives muscle protein synthesis, the physiological process where the body creates new muscle proteins, leading to hypertrophy.

And apparently, protein pays. According to CoBank research, brands can command a 12% price premium for products marketed as protein-rich. And so, the economic incentive to attach the word “protein” to anything edible has never been stronger.

The market is responding accordingly. David , founded by RXBAR co-founder Peter Rahal in September 2024, raised a $75 million Series A led by Greenoaks in May 2025, bringing its total funding to $85 million — for its bars delivering 28 grams of protein in just 150 calories and zero grams of sugar. Magic Spoon, the high-protein cereal brand delivering 12 to 14 grams of protein per serving with no sugar and low net carbs, has raised approximately $120 million, including a $106 million Series B led by HighPost Capital. And Slate Milk, the high-protein dairy brand offering 20-42 grams of protein per can, closed a $23 million Series B in September 2025 led by Foundership, bringing its total funding to $54 million.

Not All Protein Is Created Equal

I spoke with Roger Barnett, Chairman and CEO of Shaklee, a 70-year-old wellness company, which operates as a direct-to-consumer, community-marketing brand, distributing its products through a network of more than two million ambassadors across North America and Asia, about the art of engineering protein.

Shaklee has spent over $500 million on research and development across its various product lines (including nutritional and anti-aging supplements, protein shakes, liquid collagen, skincare and non-toxic household cleaners) and operates an R&D production facility in San Francisco, where every formulation moves through clinical testing and proof-of-concept work before going to market.

Barnett explained, there are several different kinds of protein and not all are created equal. “So, for example, you have collagen, which is a protein, and a peptide protein, but it doesn’t have all nine essential amino acids in it.” Three specific essential amino acids—leucine, isoleucine, and valine—are called Branched-Chain Amino Acids. They make up about 35% of the essential amino acids in your muscle proteins. Among them, leucine plays an outsized role. “It is the primary signaling molecule that triggers muscle protein synthesis, which is why high-performance protein formulations are increasingly engineered to concentrate it.” The other six essential amino acids required to build and repair muscle are histidine, lysine, methionine, phenylalanine, threonine, and tryptophan.

The company launched a new product, Shaklee Sparkling Protein, in October 2025 and showcased it the following month at the Eudēmonia Wellness Summit in West Palm Beach — a 40-gram protein sparkling water engineered to deliver the highest concentration of protein in the smallest mass, with no added sugar or cholesterol.

According to Barnett, the differentiation in Shaklee’s protein product comes from formulation discipline — stripping away the fat, sugar and carbohydrate baggage that comes with most protein products on shelves. “What separates clinical-grade protein from commodity protein is not the gram count on the package. It is the underlying ingredient design — sufficient leucine concentration and bioavailability.”

Enter Pendulum: Biotech Building Bugs to Heal the Gut

Like Shaklee, Pendulum Therapeutics is a consumer-facing company built on a foundation of clinical rigor. Its flagship products have run through peer-reviewed clinical trials, including studies published in BMJ Open Diabetes Research and Care and BMC Microbiology. Its Glucose Control product, validated in a double-blind, placebo-controlled clinical trial, was shown to reduce A1C levels by 0.6 points and post-meal glucose spikes by 32.5% in Type 2 diabetics — though it is noteworthy that the products are not FDA-approved.

Originally co-founded in 2012 by Colleen Cutcliffe, a PhD biochemist, alongside a team of scientists with backgrounds in DNA sequencing and microbiology, the gut health company is closely affiliated with actress Halle Berry, who joined as an investor and Chief Communications Officer in 2023 after being a customer of Pendulum’s products.

The founding thesis centered on a single bacterial strain: Akkermansia muciniphila. 2 “Akkermansia is probably the most important strain in your gut that you’ve never heard of,” Cutcliffe explained. “It’s known to stimulate your body’s natural GLP-1 hormone, and it's responsible for maintaining the structure of your gut lining.”

Research points to a broader range of benefits. By degrading and recycling the mucus layer, Akkermansia stimulates the gut to produce fresh, healthy mucus — repairing the intestinal barrier and preventing leaky gut. It also lowers pro-inflammatory cytokines, reducing chronic systemic inflammation. Emerging research suggests it may even boost the efficacy of immune checkpoint inhibitors in cancer patients by activating specific T-cells — a finding that has drawn significant interest from the oncology community.

"It is abundant in healthy people but is lost surprisingly easily. When you take an antibiotic, you are taking a nuclear bomb to your microbiome.” There are also several other factors that can cause a loss of Akkermansia. “We lose it due to periods of intense stress. We lose it when our circadian rhythm is disrupted. We lose it when we go through menopause," Cutcliffe elaborated.

And what makes Akkermansia deficiency uniquely difficult to treat is that it cannot be replenished through diet. “Akkermansia has not been found to date, in any food or any beverage,” Cutcliffe explained. “Things like high fibers and polyphenols can help feed it, but that means you’ve got to have some in you. And it has only been found in one place — breast milk. And so the theory is you get it from your mother as a child, and then you spend the rest of your life trying not to lose it.” Compounding the challenge, Akkermansia is an anaerobic bacterium — meaning it cannot tolerate oxygen — making it notoriously difficult to manufacture and deliver in supplement form.

In the early days, the capital raising challenge for Pendulum was significant. Cutcliffe recalls "getting rejected up and down Silicon Valley" , but she persevered, and with seed capital from the Mayo Clinic, Pendulum was able to engineer its own oxygen-free fermentation process to manufacture Akkermansia as well as other proprietary strains. The company now holds 22 patents with 63 more pending and has raised over $150 million from investors including Meritech Capital Partners, Sequoia Capital, Khosla Ventures, True Ventures, AME Cloud Ventures and the Mayo Clinic.

Pendulum products are currently sold online at Fullscript, iHerb, and Matakana, as well as on the company's website, on Amazon, and at Sprouts Farmers Market stores nationwide. The company also recently expanded its partnership with the Mayo Clinic, which will include new clinical studies evaluating microbiome-based approaches to support bone health in patients undergoing treatment for breast cancer, as well as research into the gut-skin axis and the role of the microbiome in improving the menopause transition.

Fiber's Facelift: Not Your Grandma's Metamucil

Pendulum’s best-selling product is a daily probiotic called Metabolic Daily, which has 5 different strains in it, including Akkermansia and three other proprietary bacterial strains. But the newest product represents a deliberate expansion beyond probiotics into the prebiotic category. Gut Fuel, a prebiotic fiber and polyphenol powdered blend, made up of baobab fruit pulp, acacia seyal gum, solnul resistant potato starch, oat bran and grape seed extract, is designed to blend into smoothies, sauces and yogurt — without affecting the taste.

The logic is straightforward: the bacterial strains Pendulum spent a decade manufacturing need something to eat. Without the right prebiotic fibers and polyphenols, they cannot establish, multiply, or produce the compounds that drive the health benefits the company is banking on. And only 5% of Americans are eating the amount of daily recommended fiber, 25 to 28 grams per day for women and 31 to 38 grams per day for men — “that’s like 10 cups of broccoli,” Cutcliffe said. For most consumers, the gap between what they are eating and what their microbiome actually needs is not a matter of willpower — it is a matter of practicality.

GLP-1 medications also factor into the rising importance of fiber. Because with GLP-1 drugs, it slows the emptying of your stomach, you've got a lot of people walking around who are constipated,” Cutcliffe remarked. “Just like protein is a clear solution to building muscle, fiber is the clearest solution to helping people with constipation.”

At a chef-curated luncheon hosted in New York City in March 2026, Cutcliffe made the case for a fiber facelift. “I’m not talking about old school torture in a glass,” she said. Existing fiber supplements are typically derived from seed husks and roots , and are typically thick, viscous, and bulky. Cutcliffe exclaimed, “This is not your grandma’s Metamucil! This is modern fiber.” Over the last 20 years, there has been significant research and learning about the gut microbiome and about fiber’s role in feeding the gut microbiome. “We now know that fiber is important for healthy digestion, your metabolic health, your cardiovascular health, even your immune health, even your brain health. It’s about a new standard, about a new nutrition movement.”

At the luncheon, Chef Johanna Hellrigl, a James Beard semifinalist whose cooking is rooted in food as medicine — shared her own testimonial as a woman deeply affected by gut challenges. After five rounds of antibiotics, Chef Johanna’s Akkermansia was wiped out entirely, her gut lining was severely compromised, and she developed SIBO — small intestinal bacterial overgrowth, a condition in which harmful bacteria colonize the small intestine unchecked, causing painful bloating, nutrient malabsorption, and digestive dysfunction. And so unfortunately, when she had her son via C-section, she had no Akkermansia left to pass along through breast milk. Chef Johanna emphasized the importance of optimizing the microbiome by focusing on whole foods and avoiding ultra processed foods. She also explained how she was able to incorporate the Gut Fuel prebiotic fiber, undetected, into a multi-course menu, featuring a bone broth, salad with pumpkin seeds, branzino, pasture raised chicken, organic beets with ricotta and roasted baby carrots. She shared, “At home, I would recommend mixing it into your yogurt, in a smoothie, or you could put it in a green sauce, like an herbaceous green sauce, or tzatziki. It’s such an easy thing to put in there to just add extra fiber to what you're eating.”

And just like with protein, the fiber and particularly the prebiotic fiber that feeds the gut bacteria is showing up on the grocery shelves in non-traditional places like soda, iced tea, snack bars, cereal and bagels. Perhaps most notably, Poppi, the prebiotic soda brand founded by husband-and-wife duo Stephen and Allison Ellsworth, was acquired by PepsiCo in May 2025 for $1.95 billion — a transaction that signaled to the broader consumer health market that prebiotic products had crossed into mainstream demand. Its rival Olipop, which controls roughly 60% of the global prebiotic soda market and contains 9g of plant fiber per can, raised a $50 million Series C in February 2025 led by J.P. Morgan Private Capital's Growth Equity Partners, bringing its total funding to $96 million. Supergut founded by veteran wellness executive Marc Washington, sells a clinically tested and patented prebiotic fiber blend with 6g of fiber per serving, closed a $22 million Series B in February 2025 led by Full Frame Growth Partners, bringing its total funding to approximately $36 million. And Seed Health, which has raised approximately $44 million including a $40 million Series A in April 2021 led by The Craftory, produces a prebiotic and probiotic supplement that includes 24 strains of bacteria that support gut health.

The Menopause Gut: The Next Women’s Health Conversation

The conversation that is just starting to cross over into the mainstream is related to The Menopause Gut , a recently published book by Cynthia Thurlow, a nurse practitioner and TEDx speaker. Thurlow argues that the gut microbiome shifts dramatically over the course of a woman's lifetime — peaking around age 40 — and that the hormonal changes of perimenopause and menopause accelerate microbial depletion in ways that affect immune function, metabolism, mood, cognition, and bone health.

Cutcliffe has seen the same pattern firsthand. When going through perimenopause and menopause, there’s all kinds of changes happening to the body. “One of the most common things is that people all of a sudden start to become sensitive to foods they weren’t sensitive to before, and at the same time, their metabolism is slowing down.” The science behind that experience, she argues, points directly to the microbiome. “One of the things that I was shocked to find is that if you take a woman who is between puberty and menopause and look at her microbiome, you can tell if it is a man or a woman. But after we go through menopause, I actually can’t tell you anymore. Our microbiomes start to look much more like a man's microbiome.” Pendulum is currently working with the Mayo clinic to better understand the role of the microbiome in improving the menopause transition.

As the science continues to evolve, the fiber renaissance will be fueled, at least in part, by the seventy-five million women moving through perimenopause, menopause and post-menopause, who are seeking answers to what is happening inside their bodies, and how they can better optimize bacterial strains to improve digestion and metabolic functioning. And in the meantime, I anticipate more prebiotic fiber products like Gut Fuel will begin to proliferate grocery shelves, as consumer food brands carve their piece of the fiber rush.

1. Of note, Among the GLP-1 users taking the medication primarily for weight loss — approximately 80% are women, according to research from the University of Texas Health Science Center at Houston.

2. While Akkermansia is the strain Pendulum is best known for, the company's broader portfolio is built around a curated set of next-generation probiotic strains, each selected for a specific biological function. Beyond Akkermansia muciniphila, Pendulum's products feature Clostridium butyricum and Clostridium beijerinckii , both butyrate-producing strains that fuel colon cells, support tight junctions in the gut lining, and stimulate GLP-1 production. Anaerobutyricum hallii — previously known as Eubacterium hallii — is another butyrate producer that acts as a cross-feeder, generating compounds that nourish other beneficial bacteria in the gut. Bifidobacterium infantis , a strain abundant in infants that helps establish a healthy microbiome foundation, digests complex carbohydrates and supports the production of short-chain fatty acids.

Disclosure: The author received a complimentary sample of Shaklee Sparkling Protein and was invited to attend a private luncheon hosted by Pendulum, where Gut Fuel product samples were provided. This article was reported independently and the author's editorial judgment was not influenced by the receipt of these products or experiences.