UK supplement manufacturer actually runs his capsule and tablet machines with and without fillers and added ingredients, thought this is cool and informative

First off, MCC is the ideal filler for a bunch of reasons:

* Compressibility and flow: MCC exhibits excellent powder flow properties. We us multiple grades (PH 101, PH 102, PH 200) for different formulation requirements. This enables consistent capsule fill weights and dosing accuracy.

* Chemical inertness: MCC is non-reactive with all active ingredients. This means it does not accelerate degradation, cause adsorption losses, or alter bioavailability.

* Moisture management: MCC acts as a moisture buffer, helping to protect hygroscopic ingredients and actives.

* No caloric contribution: As an indigestible fiber, MCC contributes no calories, unlike maltodextrin or rice flour.

* Hypoallergenic profile: MCC is gluten-free, vegan, allergen-free, and carries no known sensitization risks. It's about as well-tolerated as an ingredient gets.

* Regulatory acceptance: Listed in every major pharmacopoeia and approved globally; even receiving the highest safety classification from the Joint FAO/WHO Expert Committee on Food Additives (JECFA)

It's the absolute best filler to use in dietary supplements, in our experience. Moreover, not only it is not bad for you, it actually has benefits itself! It is a prebiotic fiber that improves your microbiome and improves lipid metabolism.

Dietary cellulose induces anti-inflammatory immunity and transcriptional programs via maturation of the intestinal microbiota

Dietary cellulose prevents gut inflammation by modulating lipid metabolism and gut microbiota

Structural Characteristics of Inulin and Microcrystalline Cellulose and Their Effect on Ameliorating Colitis and Altering Colonic Microbiota in Dextran Sodium Sulfate-Induced Colitic Mice

It has even been shown to increase Akkermansia, resulting in higher endogenous GLP-1 production. How it does this is actually really cool! It doesn't feed the probiotics like other fermentable fibers. It mechanically stimulates goblet cell mucin secretion, creating a richer mucosal habitat that directly supports Akkermansia, which is a mucin-degrading species. Another cool fact is that some species actually need it to flourish, not being able to eat any of the other fibers in the diet. The Fischer et al. 2020 study identified Alistipes as the microbial genus most critically dependent on dietary cellulose, being nearly undetectable in cellulose-free diet mice. A. finegoldii encodes unique genes for cellulose degradation, enabling it to thrive in cellulose-containing environments. When mice were colonized with that strain, it induced strong upregulation of IL-22 and Reg3γ, which are key proteins that maintain the intestinal barrier by segregating the microbiome from the epithelium. This provided significant protection against DSS-induced colitis. Alistipes is a member of the human core microbiota, and its deprivation under low-cellulose conditions is consistent with the epidemiological pattern of inflammatory bowel conditions in Western populations consuming low dietary fiber. This means it is actually harming people to NOT consume cellulose in their diets.

In addition, cellulose supports a different type of probiotic in your system: the cellulolytic bacteria Ruminococcus and Fibrobacter. The human colon harbors these specialized bacteria, primarily Ruminococcus champanellensis, Ruminococcus albus, Bacteroides cellulosilyticus, and members of the genus Fibrobacter, that directly ferment cellulose into short-chain fatty acids (SCFAs). This is primarily succinate, acetate, and butyrate precursors. These bacteria play a crucial role in the colonic ecosystem. Their cellulose degradation activity produces fermentation products that support secondary bacterial populations that would otherwise lack substrate. MCC as a source of crystalline cellulose provides substrate for this entire microbial grouping. So not only should you not worry about MCC in capsules, you would likely benefit some from it in there.

Cellulolytic bacteria in the large intestine of mammals

Remember, we always use no fillers or excipients if we can. That's the primary directive to my formulation team. They always try to make it work with just the supplement powder itself in a veggie capsule. For example, our Erinamax capsules have no fillers or excipients in them. It's just freeze-dried lion's mane mycelium in a veggie capsule. That's because the properties of the powder itself made it possible, so there was no reason to add more things to it for no reason. The same goes for Eurycomax. That formula just worked, so the formula itself is all that is in the capsules. These fillers add cost and labor for blending, so we would not be adding them if we didn't need to. Trust me, I have had long discussions with my formulation team on all this, and they know my directive is to use nothing if at all possible. However, capsule formulation is not as simple as many people think. It's one thing to use a Cap-M-Quick at home and eyeball relative fills without anything else in there. It's a whole other thing to make two million capsules of a formula that contains 8 active ingredients, all while ensuring every single capsule is at or above label claim, and all within 10% variance of each other... whether that production run was done in the colder and drier winter months, or in the hot humid periods during our monsoon season. Accuracy and precision is our top priority, and MCC allows us to accomplish that.