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7 Reasons GLP-1 Users Are Adding Core Fiber To Fix Nasty GLP-1 Side Effects
Your GLP-1 medication works. Unfortunately, it also comes with some pretty uncomfortable side effects. One daily scoop of this complete prebiotic system helps bring digestion back into balance with immediate gut support. 
7 Reasons GLP-1 Users Are Adding Core Fiber To Fix Nasty GLP-1 Side Effects
Better bowel movements (oh, sweet relief)
1
Better bowel movements (oh, sweet relief) 
A well known side effect of GLP-1s is slowed digestion. This often leads to constipation, bloating, and digestive discomfort.

Core Fiber delivers 6g of diverse, prebiotic fiber to help keep things moving so you can finally feel comfortable—no harsh laxatives required.
Fill major fiber gaps on GLP-1s
2
Fill major fiber gaps on GLP-1s
GLP-1s reduce appetite. When you eat less, you’re not just cutting calories—you’re cutting essential nutrients like fiber, which your gut depends on to function properly.

Core Fiber restores what your diet (and gut) is missing with a complete blend of diverse, prebiotic fibers  designed to mirror a fiber-rich whole foods diet.
Complete fiber that mirrors whole foods
3
Complete fiber that mirrors whole foods
Most fiber powders and gummies use only a single type of fiber whose sole purpose is to help you go #2. 

But our bodies need many different types of fiber – like we get from whole foods – to do different jobs. Some help food and waste move through your digestive system. Some feed your gut microbiome. Some help stabilize blood sugar and cholesterol.

Core Fiber combines a wide range of clinically-studied fibers that work together to keep your digestion moving and your gut thriving.
No more feeling bloated or gassy
4
No more feeling bloated or gassy
When you’re not eating enough of the right fibers, your digestion is thrown off – leading to gas and uncomfortable pressure buildup. 

Core Fiber helps move food and waste through your gut gently and efficiently, so you feel light and balanced.
Have energy all-day
5
Have energy all-day
Eating less can cause energy dips and crashes.

Core Fiber slows how quickly nutrients are absorbed—supporting more stable blood sugar levels and consistent energy throughout the day.
Long-term metabolic support
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Long-term metabolic support
Without proper nutrition, GLP-1s can put real strain on your metabolism.

The prebiotic fibers and resistant starches in Core Fiber help support insulin sensitivity, nourish beneficial gut bacteria, and promote long-term metabolic health.

That’s why fiber becomes essential on GLP-1s—without it, you risk ending your GLP-1 journey with a slower, less supported metabolism.
Easy to take. Easy to stick with.
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Easy to take. 
Easy to stick with.
Core Fiber is easy to mix into anything – water, coffee, smoothies, yogurt – without even knowing it’s there. 

One scoop is the most complete way to support your gut and digestive health while everything else in your diet is changing.
Doctor Formulated
Clinically-Studied Ingredients
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GLP-1's Best Friend: Complete Gut Support

A multi-fiber, prebiotic blend designed to support digestion, energy, and metabolism — especially on a GLP-1 journey.

Flavor: Unflavored

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More Fiber, More Support:
Each serving delivers 6g of fiber—more than most powders or gummies—so you get real digestive support you can feel.

Soluble & Insoluble Fiber:
Core Fiber includes both types of fiber your body needs. Soluble fiber feeds your gut microbes and supports smoother digestion. Insoluble fiber helps keep everything moving—naturally and effectively.

Built for Real Life:
Whether you’re lifting, working, parenting, or all of the above, Core Fiber fits right in. It supports digestion, nutrient absorption, and all-day energy—so you can feel lighter, stronger, and more balanced.

Clean, Easy, Effective:
No artificial flavors. No fillers. Just a gut-friendly blend that mixes fast, tastes great, and actually works.

Core Fiber is made with a blend of five all-natural, plant-based fibers selected for their numerous prebiotic benefits and gut-friendly profile. 

Core Fiber contains:

NO sugar
NO artificial ingredients
NO gluten
NO soy
NO dairy
NO GMOs


It is also vegan and keto-friendly.

Science
Fiber is one of the most well-studied and widely recommended nutrients in human health, with thousands of clinical studies supporting its role in digestion, microbiome health, metabolic function, and even skin clarity and immune support. Core Fiber is formulated in collaboration with leading MDs and PhDs to deliver the most effective types and forms of fiber—no filler ingredients, no gimmicks. Just real results rooted in science. 

Third Party Testing
Our products undergo rigorous testing to ensure quality and purity. We work with highly accredited labs to verify that Core Fiber meets all label claims and passes contaminant screenings for pesticides, heavy metals, and microbial contaminants.

Certifications
Manufactured in SQF, GMP, and FDA certified facilities in the U.S., and thoroughly tested for heavy metals and contaminants.

Mix one scoop with 8-12 oz of water or your favorite beverage (or food!) daily. For best results, take it consistently—ideally around the same time each day. Increase to 2-3 scoops daily for maximum effect.

New to fiber? Start with half a scoop for the first 4 days to let your body adjust, and make sure you’re drinking plenty of water.

Core Fiber comes in two flavors:

Unflavored - a neutral, tasteless powder designed to be mixed in anything without the grit or weird aftertaste. Most customers add this to beverages like water and coffee, or to snacks like yogurt and oatmeal. 

Strawberry Kiwi -  a delicious combo of sweet strawberry and tangy kiwi flavors. The perfect flavor boost for water, protein shakes, or yogurt—no grit, no weird aftertaste. 

CORE FIBER

CORE FIBER

$35.99

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StarFour Non GMO
StarFour NO Sugar
StarFour NO Gluten
4.8/5 Avg. Rating 
The 'Missing Piece' to Your GLP-1 Routine.
Thousands of users have conquered the side effects and reclaimed their digestive comfort with Core Fiber.
More Regular
Ive been looking for an easy way to get more fiber in my diet. Core Fiber mixes smoothly with my morning smoothie (and even in just water, its not bad), and I notice I feel less sluggish during the day. My digestion seems more regular, and I'm not as bloated after meals. It's made a noticeable difference for me
E & Y
Verified Purchase
Truly Unflavored
Core Fiber is great and has become a part of my daily routine. Its a great and easy way to help me stay regular and unlike make others, doesn't taste horrible.
Danny G.
Verified Purchase
Perfect & Easy Fiber Supplement
Works perfectly! Dissolves really easy in a glass of water. Also works great with your daily protein shake or smoothie, has no taste and blends perfectly. Highly recommend.
Linda D.
Verified Purchase
Perfect Daily Fiber
This is such a great way to add fiber on a daily basis. So easy to add to oats, yogurt or smoothies and the taste is good/neutral. The powder is very dissolvable, so you don’t end up with the chunky texture of other supplements.
Emily B.
Verified Purchase
Fantastic Daily Fiber Boost
Been mixing this into my breakfast meals for the last month and am already seeing better digestion and more consistent energy throughout the day. Simple way to add more fiber without changing my routine!
Brenda
Verified Purchase
Better Than Psyllium Husk
Traded in my psyllium for this and it was a great move. Want to ensure I'm having at least 30g of fiber a day. I love how Core Fiber blends really easily in my smoothies and protein shakes and isn't grainy or chalky or nasty. Easy to eat, doesn't bulk my stomach, and is a great consistency that blends really well. Love it - this is definitely my new fiber going forward.
Sean K.
Verified Purchase
Great Addition to My Morning Smoothie!
I have been using for 2 months. Started more for the combination of prebiotic and fiber as an add on to my morning regimen. I feel less bloated and less upset stomach episodes. Feeling more energy is probably a combination of multiple changes- more water, no caffeine and healthy nutrition!
Jen B.
Verified Purchase