How We Source Our Supplements: Inside The Fit Nerd's Manufacturing

Here's a question almost nobody asks before they buy a tub of protein: who actually made this?

Not who sells it. Not whose logo is on the front. Who physically weighed the powder, ran the blender, filled the jar, and signed off on the batch. For a huge share of supplement brands, the honest answer is "we don't really know" — because they bought a stock formula from a contract manufacturer, slapped a label on it, and shipped it.

We think that's backwards. So this post is the tour. What the rules actually require, what we require on top of that, and what you should be asking any brand — including us — before you swallow something they made.

First, the part most brands hope you don't look up

The FDA does not approve dietary supplements before they go on sale^[5]. There is no pre-market review, no agency taste-test, no green light. Under the Dietary Supplement Health and Education Act, the manufacturer is the party responsible for making sure a product is safe and that its label is truthful and not misleading — and the FDA's role is largely to act after a product is already on the market^[5].

That is why "FDA registered" on a supplement label is weaker than it sounds. It means a facility is on file with the agency. It is not a seal of approval, and it says nothing about whether what's in the jar matches what's on the panel.

So if approval isn't the bar, what is? The real bar is cGMP.

cGMP: the rules that actually bite

Current Good Manufacturing Practice for dietary supplements is federal law, written into 21 CFR Part 111^[1]. It's not a marketing badge. It's a binding regulation that tells a manufacturer how it must run, and it is far more demanding than most people realize.

Part 111 requires, among other things, that a manufacturer^[1]:

• Establish and follow written procedures for every step of production, packaging, labeling and holding — not tribal knowledge, not "the way Dave does it."
• Maintain a quality control unit with the authority to approve or reject ingredients, in-process material, packaging, labels, and finished batches.
• Verify the identity of incoming ingredients before they're used, and confirm that other component specifications are met.
• Keep batch production records so any finished jar can be traced back through its own manufacturing history.
• Control the physical plant and equipment — sanitation, calibration, cleaning, maintenance.
• Investigate and document product complaints.

The FDA's own overview of cGMP for food and dietary supplements lays out the same framework in plainer language, and makes clear that facilities are subject to inspection^[2]. That's the meaningful mechanism: not pre-approval, but enforceable manufacturing standards plus the possibility of someone showing up to check.

What we look for in a manufacturing partner

We don't own a factory. Very few supplement brands our size do, and the ones that claim to usually mean they rent space in someone else's. We're not going to pretend otherwise.

What we do is choose partners against a checklist and refuse to move on it. In practice, that means:

1. The facility operates under cGMP as defined in 21 CFR Part 111^[1] — with the documentation to demonstrate it, not just a line in a sales deck.
2. Incoming ingredient identity is verified before anything goes into a blend^[1]. This is the single most-skipped step in cheap manufacturing, and it's the one that determines whether your "lion's mane" is lion's mane.
3. Finished batches are tested and the records exist. If a partner can't produce a batch record on request, that's a dealbreaker, not a negotiation.
4. Every active ingredient is disclosed at its dose. No proprietary blends hiding a dusting of the expensive stuff behind a wall of rice flour.

That last one isn't a regulatory requirement. It's ours. It's also the reason our labels are sometimes less flattering than a competitor's — you can see exactly how much of everything you're getting, which means you can compare us to anyone.

Third-party marks: what NSF and USP actually mean

Beyond the legal floor, there are voluntary certifications. Two are worth knowing, because they're the ones that carry real weight and the ones most often name-dropped without being earned.

Mark	What it checks	Who it's for
NSF Certified for Sport[3]	Screens products for banned substances and confirms that label contents match what's inside; includes facility auditing.	Drug-tested athletes — collegiate, professional, military.
USP Verified[4]	Verifies ingredient identity, potency and purity, and audits manufacturing against good manufacturing practices.	Anyone who wants independent confirmation the panel is accurate.

Here's the part we want to be straight about: these marks are product-specific, not brand-wide. A company can have one certified SKU and market as though the whole catalog is covered. If a certification matters to you — and if you're drug-tested, it absolutely should — look the specific product up in the certifier's own public database rather than trusting a logo on a website^[3,4].

How to vet any supplement brand in about five minutes

Use this on us. Use it on everyone.

• Can you see every dose? If a Supplement Facts panel lists a "proprietary blend" with one combined number, you cannot tell how much of anything you're getting.
• Does the brand say where it's made and under what standard? Vague gestures at "the highest quality" are not an answer. "cGMP under 21 CFR Part 111" is.
• Is "FDA approved" anywhere on the page? If so, leave. No dietary supplement is FDA approved^[5].
• If a third-party mark is claimed, is the specific product listed in the certifier's database?^[3,4]
• Will they answer a direct email about testing? A brand that dodges this question has told you what you need to know.

Our answers, for the record: full doses on every panel, cGMP manufacturing, and a real human on the other end of our contact page if you want to ask about a specific batch.

Frequently asked questions

Does "FDA registered" mean my supplement is FDA approved?

No. The FDA does not approve dietary supplements before they're sold; manufacturers are responsible for the safety of their products and the truthfulness of their labels^[5]. Facility registration is an administrative filing, not an endorsement of any product made there.

What does cGMP actually require?

cGMP for dietary supplements is set out in 21 CFR Part 111 and requires written procedures, a quality control unit with authority to reject material, identity verification of incoming ingredients, batch production records, equipment and facility controls, and documented complaint handling^[1,2].

Is NSF Certified for Sport the same as USP Verified?

No. NSF Certified for Sport is built around banned-substance screening and label-content confirmation for drug-tested athletes^[3]. USP Verified focuses on ingredient identity, potency and purity, plus manufacturing audits^[4]. They answer different questions.

Why don't all supplement brands publish their doses?

Because proprietary blends let a brand list impressive-sounding ingredients without revealing how little of each one is present. Disclosing full doses removes that cover and makes a formula directly comparable to competitors' — which is exactly why we do it.

How can I check a specific product's certification myself?

Both NSF and USP maintain public listings of the products they've certified^[3,4]. Search the exact product name there. A logo on a brand's own website is a claim; the certifier's database is the evidence.

Where to start

If you want to see what full-dose labeling looks like in practice, two good places to look are our Creatine Monohydrate — one ingredient, one number, nothing to hide behind — and our Grass-Fed Hydrolyzed Collagen Peptides, where the gram dose is printed plainly because the gram dose is the whole point. Or browse the full Bestsellers collection and read the panels before you read the marketing.

We'd rather you buy from us because you checked. That's the entire idea.

References

1. U.S. Government Publishing Office. 21 CFR Part 111 — Current Good Manufacturing Practice in Manufacturing, Packaging, Labeling, or Holding Operations for Dietary Supplements. Electronic Code of Federal Regulations. View source
2. U.S. Food and Drug Administration. Current Good Manufacturing Practices (CGMPs) for Food and Dietary Supplements. View source
3. NSF. Certified for Sport Program. View source
4. U.S. Pharmacopeia. USP Verified Mark. View source
5. U.S. Food and Drug Administration. Information for Consumers on Using Dietary Supplements. View source

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.