TL;DR

• On March 20, 2026, FDA's Human Foods Program sent Nupack Inc. a warning letter citing one product line — Cardiag, Diabetech, Cleanse-CAMP, MACA, Kidney Cleanse, and Pure Psyllium Husk — under three separate legal theories at once: unapproved new drug, misbranded drug, and adulterated dietary supplement (FDA Warning Letter, Nupack Inc., MARCS-CMS 722113, March 20, 2026).
• The trigger wasn't the ingredients. It was label and website language like "Diabetech powder for Diabetics" and claims that MACA "may help to reduce erectile dysfunction" — phrasing FDA read as treating or preventing disease under section 201(g)(1)(B) of the Food, Drug, and Cosmetic Act [21 U.S.C. 321(g)(1)(B)] (same letter).
• Four separate 21 CFR Part 111 manufacturing failures — no product specifications, no master manufacturing record, no batch production record, no returned-product procedure — stacked an adulteration citation on top of the drug-claim problem (same letter).
• This isn't a new failure mode. In May 2022, FDA sent the same core citation — disease claims plus missing new dietary ingredient notifications — to 11 sports-nutrition firms in a single batch (FDA, Warning Letters to Companies for Selling Adulterated Supplements, May 9, 2022).
• Below: the specific claim types that cross the disease-claim line, the CGMP failures FDA layers on top once it's already looking at your labels, and the disclaimer and notification steps that keep a structure/function claim legal.

When Does a Dietary Supplement Become an "Unapproved New Drug" to FDA?

A supplement crosses into drug territory the moment its label or marketing claims it treats, cures, mitigates, or prevents a disease — not when a regulator decides the ingredients are unsafe. FDA's March 2026 warning letter to Nupack Inc. makes that distinction unusually visible, because the agency cited the same product line as an unapproved drug, a misbranded drug, and an adulterated supplement, in the same document.

Compliance teams reading a letter like this for the first time often assume the ingredient list was the problem. It wasn't. Six products, a diabetes powder, a cardiovascular blend, a laxative, a kidney formula, a libido supplement, and a fiber product, were each pulled into drug status by specific phrases printed on their own labels and websites.

The claim, not the ingredient, is what FDA reads first

FDA's letter to Nupack quotes the exact label and website language it relied on. Here is what tipped five of the six products into "new drug" territory under section 201(g)(1)(B) of the Food, Drug, and Cosmetic Act [21 U.S.C. 321(g)(1)(B)]:

1. Disease names inside the product name itself. "Diabetech" — marketed as "Diabetech powder for Diabetics" — put a disease name in the branding before a single ingredient claim was made (FDA Warning Letter 722113).
2. Specific physiological outcomes tied to a named condition. Cardiag's website claimed the product may help with "protecting against clots which can cause heart attacks and stroke" and "reduce risk for repeat heart attacks" — outcome language, not a general wellness claim (same letter).
3. Direct substitution language for an approved treatment class. Cleanse-CAMP was marketed as a "healthy alternative to over-the-counter laxatives" — language that positions the product as a replacement for a recognized drug category (same letter).
4. Named-condition treatment claims for a lifestyle product. MACA's labeling claimed it "may help to reduce erectile dysfunction," a specific diagnosable condition, not a structure/function statement about libido or energy in general (same letter).
5. Cholesterol-reduction claims without the disclaimer. Pure Psyllium Husk's "support to lower LDL Cholesterol" claim reads as a cardiovascular disease claim absent the structure/function disclaimer FDA requires for that category (same letter).

Once FDA determined these products were drugs under 201(g)(1)(B), the rest of the analysis followed automatically. Products intended to cure, mitigate, treat, or prevent disease are "new drugs" under section 201(p) [21 U.S.C. 321(p)] unless generally recognized as safe and effective for that use — and new drugs cannot be introduced into interstate commerce without prior FDA approval under sections 301(d) and 505(a) [21 U.S.C. 331(d), 355(a)]. None of Nupack's products had that approval.

Three of the six — Cardiag, Diabetech, and MACA — picked up a second violation on top of the drug determination: misbranding under section 502(f)(1) [21 U.S.C. 352(f)(1)], because a product intended to treat a disease that isn't self-diagnosable or self-treatable can't legally carry "adequate directions for use" written for a layperson. FDA's letter states plainly that products meant for conditions requiring "the supervision of a licensed practitioner" fail that standard by definition.

Where the DSHEA line actually sits

The Dietary Supplement Health and Education Act of 1994 lets supplement makers describe a product's effect on the body's structure or function — supporting healthy blood sugar levels already in the normal range, for instance — without FDA preapproval. What it does not allow is a claim that the product diagnoses, treats, cures, or prevents a disease. FDA's own regulation on this point, 21 CFR 101.93, requires any structure/function claim to carry a specific, unmodified disclaimer, in boldface: "This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease." The claim itself must also be substantiated before it's made, and the company must notify FDA of the claim within 30 days of first marketing the product under 21 CFR 101.93 (FDA, Structure/Function Claims).

"Diabetech powder for Diabetics" isn't a structure/function claim with a missing disclaimer. No disclaimer legally rescues a disease name inside the product name itself, or a claim that a product prevents a heart attack. That's the practical test compliance teams miss most often: the disclaimer fixes an ambiguous claim, not an explicit one.

The manufacturing side FDA cited in the same letter

Once FDA is reviewing a firm's labels, an inspection of the manufacturing facility routinely follows — and CGMP failures for dietary supplements carry their own adulteration theory entirely separate from the disease-claim analysis. Nupack's facility inspection, conducted August 20 through September 24, 2025, surfaced four distinct 21 CFR Part 111 violations, each cited by its own subsection:

1. No product specifications for identity, purity, strength, and composition, required under 21 CFR 111.70(e) — FDA states Nupack could not produce these specifications for Cardiag, Cleanse-CAMP, or MACA 1000 mg at all (FDA Warning Letter 722113).
2. No written master manufacturing record for each unique formulation and batch size, required under 21 CFR 111.205(a) (same letter).
3. No batch production record generated at time of manufacture, required under 21 CFR 111.255(a) (same letter).
4. No written procedure for returned product — receipt, destruction, salvage criteria, or the investigation required when a return implicates other batches — required under 21 CFR Part 111, Subpart N (same letter).

These four gaps made Cardiag, Cleanse-CAMP, and MACA 1000 mg adulterated under section 402(g)(1) of the Act [21 U.S.C. 342(g)(1)] independent of the disease-claim problem. A firm that fixed every label tomorrow would still be sitting on an open adulteration citation until its Part 111 quality system existed on paper, not just in practice.

This is a recurring pattern, not a one-off

FDA's Human Foods Program has run this exact two-part playbook — disease claims plus manufacturing or ingredient-notification failures — against groups of firms before, not just single companies. In May 2022, FDA sent warning letters to 11 dietary supplement firms in one batch, including Advanced Nutritional Supplements, Assault Labs, IronMag Labs, Complete Nutrition, and Steel Supplements, for selling products containing ingredients like higenamine, hordenine, and octopamine without the new dietary ingredient (NDI) premarket notification required for any dietary ingredient not present in the food supply before October 15, 1994 (FDA, Warning Letters to Companies for Selling Adulterated Supplements, May 9, 2022). That notification is due at least 75 days before the product enters interstate commerce, under section 413(a)(2) of the Act [21 U.S.C. 350b(a)(2)] (FDA, New Dietary Ingredients in Dietary Supplements — Background for Industry). That letter also noted some of the same firms' products were unapproved new drugs, for the identical disease-claim reason FDA cited Nupack for four years later.

The mechanism hasn't changed. What changes is which ingredient or claim triggers the review — an unnotified NDI in 2022, a diabetes-named product in 2026.

What this means for a supplement compliance program

A label review that only checks for the standard DSHEA disclaimer misses the failure mode FDA actually cited here. The disclaimer question is secondary. The first question has to be whether any claim — in the product name, on the label, or on the marketing website FDA will screenshot as evidence — names a disease or a specific diagnosable condition rather than a general structure or function. Nupack's letter shows FDA reads website copy with the same weight as the physical label, and reads a product's own name as a claim in itself.

Second, a Part 111 quality system has to exist as a paper trail before an inspector asks for it. Specifications, master manufacturing records, batch production records, and a returned-product procedure are four specific, checkable documents — not a general assertion that the facility follows good practice.

FAQ

Is every dietary supplement disease claim an automatic warning letter?

No. FDA reviews websites and labels on its own schedule and by complaint, and enforcement is not comprehensive or immediate. But once FDA does review a product, a disease claim inside the product name or in outcome language ("may prevent stroke," "reduces erectile dysfunction") has consistently resulted in an unapproved-new-drug citation, as in the Nupack letter above.

Can adding the standard DSHEA disclaimer fix a disease-name product like "Diabetech"?

No. The 21 CFR 101.93 disclaimer applies to structure/function claims that could be read ambiguously. It does not convert an explicit disease claim, or a disease name inside the product's own branding, into a legal structure/function claim.

What's the difference between the 30-day and 75-day notification requirements?

The 30-day requirement, under 21 CFR 101.93, applies to notifying FDA of a structure/function claim already in use. The 75-day requirement, under section 413(a)(2) of the Act [21 U.S.C. 350b(a)(2)], is a premarket notification for a new dietary ingredient not previously present in the food supply — a separate filing tied to the ingredient itself, not the claim.

Does FDA need to find an actual health harm before citing adulteration under 21 CFR Part 111?

No. The Nupack letter cites Part 111 violations — missing specifications, missing manufacturing and batch records, no returned-product procedure — as adulteration on their own, without alleging any specific consumer harm from those gaps.

Who issues dietary supplement warning letters at FDA now?

FDA's Human Foods Program, formed in 2024, issues these letters through its Office of Enforcement. The Nupack letter was signed by the Director of that office, not by CDER, which issues drug-manufacturing warning letters for approved pharmaceuticals.

How long does a firm have to respond to a letter like this?

FDA gave Nupack 15 working days to respond in writing with specific corrective steps, or to state the reason for a delay — the same response window FDA uses across most warning letter categories, not one specific to dietary supplements.

Sources: FDA Warning Letter, Nupack Inc., MARCS-CMS 722113, March 20, 2026; FDA, FDA Sends Warning Letters to Multiple Companies for Illegally Selling Adulterated Dietary Supplements, May 9, 2022; FDA, Structure/Function Claims; FDA, New Dietary Ingredients in Dietary Supplements — Background for Industry. Related: What Is CGMP? FDA's Core Manufacturing Standard, Explained, How long does a company have to respond to an FDA Warning Letter?, What actually makes an FDA warning letter response "adequate" enough to close out?. Byline: The Argus Regulatory Analysis Team. Published 2026-07-16.

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