Product Description
You're not struggling with a fueling problem. You're fighting a gut problem. If you've ever dealt with mid-race GI distress, unpredictable digestion during big training blocks, or wild hunger swings that derail your recovery, your gut is the limiter long before your legs are.
SwissRX Fiber is the first fiber supplement actually designed for endurance athletes' guts—not bathroom emergencies.
Built for Performance, Not Bloat Delivers 11g of strategically selected fibers that won't congest, clump, or turn into gel in your bottle. Unlike traditional fiber supplements that expand in your stomach and wreck your training, this next-generation formula stays smooth from first sip to finish. You can sip it throughout the day or enjoy it over ice—no "mix and chug" panic required.
Feeds the Bacteria That Matter This isn't generic psyllium husk. SwissRX Fiber specifically supports keystone gut species like Akkermansia, Bifidobacterium, and F. prausnitzii—the bacteria linked to improved gut barrier integrity, better carbohydrate tolerance, and reduced inflammation under training stress. Translation: a gut that holds up when volume is high.
Stabilizes Energy Without the Crashes Through short-chain fatty acid production, SwissRX Fiber helps stimulate GLP-1 and PYY—hormones that control blood sugar response and satiety signals. That means fewer wild hunger swings during big mileage weeks and more consistent energy when you're stacking hard days back to back.
The formula combines eight clinically researched fiber sources—resistant starches, fruit fibers, beta-glucans, and prebiotic fibers—to increase microbial diversity and support regularity without urgency. This is gut support that compounds over time, not just a short-term fix.
How to Use SwissRX Fiber
Daily: Mix 1 scoop (16.7g) with 6-8 oz of water once daily, ideally in the morning or between meals. Use liquids below 140°F to preserve the prebiotic activity.
Timing Strategy: Take it away from your hardest training sessions to avoid any fullness during workouts, but make it a non-negotiable part of your daily routine.
Pro Tip: Start with half a scoop for the first week if you're not used to higher fiber intake, then gradually increase to the full serving as your gut adapts.
Elite athletes supplementing with just 6-7g of fiber daily for 8 weeks showed improved gut microbiome composition, enhanced body composition, better fatigue recovery markers, and measurable improvements in athletic performance. SwissRX Fiber delivers nearly double that amount with a more diverse fiber profile.
This isn't just another fiber supplement. This is your microbiome foundation—the base work that makes your nutrition strategy, recovery protocols, and training adaptations actually deliver results.
Always Happy Promise: Don't like a product? Tell us within 30 days of receipt and we'll make it right and make you happy. Here at The Feed, we want you to love your experience and the sports nutrition products you purchase. If, for any reason, you are not satisfied with your nutrition specific purchase, tell us.
We do not accept returns on food items that have been opened, but we will issue a store credit if you are unsatisfied. In the event of a return, you must first contact us before sending back a return shipment.
Consumable products over $40 receive a 50% store credit. This includes specialty nutrition products such as ketones or supplements/vitamins.
SwissRX Fiber FAQ's
Everything you need to know before getting started.
Mix 1 scoop with 6-8 oz of water once daily, ideally in the morning or between meals. Avoid taking immediately before hard workouts to prevent any digestive discomfort during training.
Unlike traditional fiber supplements that expand and cause bloating, SwissRX Fiber uses gentle, highly tolerable fiber sources designed specifically to avoid cramping and urgency. It stays smooth in your bottle and works gradually to support regularity without digestive emergencies.
SwissRX Fiber combines 8 clinically researched fiber sources that specifically feed beneficial gut bacteria like Akkermansia and F. prausnitzii. It doesn't congest or clump like psyllium-based products, and it supports energy stability through natural GLP-1 production—not just bowel movements.
If you're new to fiber supplements, start with half a scoop for the first week to allow your gut to adapt, then increase to the full serving. This gradual approach minimizes any initial adjustment period.