Samyang Roundsquare is entering the U.S. longevity supplement market with Spindle Muscle+, a postbiotic formula built around Akkermansia MYO™ — a pasteurized, heat-stabilized strain of Akkermansia muciniphila studied for its role in gut barrier integrity and age-related muscle decline. The brand, launched under Samyang America, marks one of the first commercial applications of the gut–muscle axis as a primary structure-function claim in the finished supplement category.
The Clinical Evidence
The Akkermansia MYO™ ingredient has been evaluated in a 12-week, randomized, double-blind, placebo-controlled trial conducted in adults aged 60–80. Results from that third-party study — data on file — showed a 14.1% increase in muscle power versus control, a 10.4% improvement in hamstring strength, and a 5.0 percentage-point gain in grip strength. The trial also tracked two biomarkers with direct relevance to muscle metabolism: prealbumin levels rose 5.6 percentage points versus control, signaling improved capacity for muscle maintenance and repair, while myostatin — the signaling protein that suppresses muscle growth when chronically elevated — fell 37.8 percentage points versus control. Those are meaningful clinical endpoints for a single-ingredient postbiotic, and the 12-week duration and gold-standard methodology give formulators a defensible evidence package. The underlying mechanism links A. muciniphila to gut barrier function, systemic inflammation modulation, and downstream effects on protein synthesis — a pathway supported by a separate Nature Medicine study (Depommier et al., 2019) in overweight adults with metabolic syndrome.
Because Akkermansia MYO™ is pasteurized rather than live, it qualifies as a postbiotic under the ISAPP definition and offers practical formulation advantages: the finished product is shelf-stable for up to two years without refrigeration, enabling conventional retail and e-commerce distribution without cold-chain logistics. Spindle Muscle+ was developed with an FDA-reviewed New Dietary Ingredient (NDI) notification, adding a regulatory credibility layer that distinguishes it from many botanical and probiotic launches in the longevity segment.
Market Positioning
Spindle is targeting health-invested adults in their 40s and 50s who are approaching muscle health proactively — a cohort that skews toward science-backed claims and is increasingly skeptical of single-nutrient protein and amino acid supplements. The brand also explicitly names GLP-1 medication users as a priority audience, addressing the well-documented risk of lean muscle loss that accompanies rapid weight reduction in that population. That GLP-1 adjacency is a smart move: as semaglutide and tirzepatide prescriptions continue to scale, the supplement industry is racing to develop evidence-based muscle and metabolic support products for this underserved cohort.
Formulation specs reflect clean-label positioning: gluten-free, non-GMO, free from egg, soy, wheat, nuts, fish, and shellfish, with no artificial sweeteners, color additives, or preservatives. Production is GMP-certified. Ahjin Kim, Head of R&D at Samyang Healthcare, framed the launch around data discipline: "Spindle Muscle+ reflects our commitment to formulating from data, not assumptions." Faissal Tahiri, Head of Healthcare at Samyang America, added that the product brings forward "a science-led approach that looks at the biological systems influencing muscle function."
What Operators Should Watch
The gut–muscle axis is an emerging but credible area of postbiotic and gut-health research, and Spindle represents one of the more rigorous commercial translations of that science to date. For contract manufacturers, white-label operators, and finished-product brands tracking the longevity and healthy-aging segment, the NDI filing and RCT data set a relatively high evidence bar for competitive positioning. The product is currently available direct-to-consumer at us.spindle.bio, with broader channel distribution not yet announced.
Written by Michael Politz, Author of Guide to Restaurant Success: The Proven Process for Starting Any Restaurant Business From Scratch to Success (ISBN: 978-1-119-66896-1), Founder of Food & Beverage Magazine, the leading online magazine and resource in the industry. Designer of the Bluetooth logo and recognized in Entrepreneur Magazine's "Top 40 Under 40" for founding American Wholesale Floral, Politz is also the Co-founder of the Proof Awards and the CPG Awards and a partner in numerous consumer brands across the food and beverage sector.
