AAFCO Versus FDA Oversight of Dog Supplements, Explained

By Kaitlyn Krebs, DVM, MBA, DABVP (Canine/Feline)

✓ Medically reviewed by Kaitlyn Krebs, DVM, MBA, DABVP (Canine/Feline) — August 13, 2026 For general education — not a substitute for veterinary care.

Reading labels · August 14, 2026 · 6 min read

AAFCO writes model standards states can adopt, while the FDA decides whether a dog supplement counts as food or drug.

A retriever mix named Dozer came into my exam room a few years back because his owner, a nurse working night shifts, wanted to switch him off a $60-a-month joint chew to something she’d found for $22 online. She set both bottles on the table and asked me a question I hear constantly: “Is one of these actually regulated, or are they both just guessing?” I told her the honest answer, which surprises most owners: neither the chew she’d been buying nor the cheaper one had been reviewed by a federal agency before it hit the shelf. What differs is which rulebook each company chose to follow, and how seriously they followed it.

That distinction — a voluntary standards body versus a federal regulator with actual enforcement teeth — is the whole story of how dog supplements get overseen in the US. It’s also where most label confusion starts.

AAFCO writes the recipe book; it doesn’t run the kitchen

The Association of American Feed Control Officials doesn’t have independent regulatory authority. It’s a nonprofit made up of state and federal officials that publishes model regulations, ingredient definitions, and labeling guidance — a kind of shared dictionary that state feed-control programs can adopt into their own laws. According to FDA’s Regulation of Pet Food, enforcement of pet food and feed law happens primarily at the state level, with FDA’s Center for Veterinary Medicine providing federal oversight for safety, adulteration, and misbranding.

So when a bag says “meets AAFCO nutrient profiles,” that’s a manufacturer’s claim that the product was formulated against AAFCO’s published standards — not proof that any government agency inspected it. AAFCO doesn’t test products, license them, or issue approvals. It writes the recipe book. Somebody else has to actually cook to it, and somebody else has to check the kitchen.

The FDA question that actually has legal weight: food or drug?

Here’s the part that surprises owners more than anything: there is no federal “dietary supplement” category for animals at all. Human supplements have DSHEA, the 1994 law that carved out a distinct legal lane for vitamins and herbal products. Dogs don’t get that lane. Per the FDA’s own guidance, products marketed as animal dietary supplements are legally classified as either animal food or a new animal drug, depending on their ingredients and the claims made about them — there’s no third option (Compliance & Enforcement).

That classification matters enormously. A joint chew that says “supports mobility” is making a structure/function claim and can generally sit in the food lane. A product that claims to “treat arthritis” or “cure” anything has crossed into new-animal-drug territory — and an unapproved new animal drug is something FDA can act against, because it hasn’t gone through the safety and efficacy review a real veterinary drug requires. The wording on the label isn’t just marketing style. It’s the line between two entirely different regulatory categories, and companies that get sloppy with claims are the ones that draw FDA attention.

Where NASC fills the gap nobody legislated

Because there’s no statutory middle ground, a private nonprofit stepped in to build one. The National Animal Supplement Council was founded in 2001 specifically because the industry recognized this regulatory vacuum and wanted a way to signal quality without waiting on Congress. NASC-certified companies go through third-party audits covering ingredient traceability, labeling accuracy, and adverse-event reporting — the kind of scrutiny that AAFCO membership alone doesn’t require and that FDA doesn’t provide unless something’s already gone wrong.

I’ve watched this play out in my own practice with a 9-year-old Lab named Winnie, brought in by an owner who managed a tight budget on a single income. Winnie was starting to hesitate before jumping into the car and taking the stairs more slowly in the evenings — changes the owner had noticed over about six weeks, mostly after her Sunday walks in the park near their apartment. She’d already bought a bargain glucosamine chew from a gas-station rack, drawn in by the price, and wanted to know if it was worth continuing before she spent more on something else. I couldn’t tell her whether that specific product had ever been tested, because nothing in its labeling pointed to any third-party certification, no NASC seal, no batch documentation she could ask for. That’s not proof it was unsafe. It’s proof she had no way to check. We talked about weighing the twenty extra dollars a month against the actual paper trail a certified product could offer, and she switched to one she could verify.

That’s the crux of it, and it’s why I come down where I do: weigh the cost and the access before the ideal. The ideal is a fully harmonized federal supplement category with premarket review, the kind DSHEA gives human products. That doesn’t exist for dogs, and recent efforts — including the NutraIngredients: Animal Health Supplement Act NASC has pushed to modernize this gap — show the industry itself knows the current patchwork is inadequate. Until something like that passes, the strongest counterargument to “just buy NASC-certified” is real: certification costs money, and that cost gets passed to owners who are already stretched. A single parent budgeting for a senior dog’s joint support may not be able to justify the premium every certified brand charges. I don’t dismiss that trade-off. But I still land on certification as the better default, because the alternative — a label with no audit trail behind it — asks the owner to trust a company’s word with zero verification, and that’s a worse bet than the extra cost most months.

Reading a label like a regulator would

Practically, here’s what I tell owners to check, in order: does the label make a food-style claim (support, maintain, promote) rather than a drug-style claim (treat, cure, prevent disease)? Is there a NASC seal, and can you find the company’s quality-assurance documentation if you look? Does the company publish a certificate of analysis on request? None of these questions require legal training. They just require knowing that “AAFCO compliant” describes a recipe, not an inspection, and that FDA’s real leverage kicks in only when a claim crosses into drug territory.

For deeper label literacy, our companion piece on cGMP Certification vs. NASC Membership breaks down the manufacturing side of this same gap, and our guide to chew vs. powder vs. liquid formats covers how delivery format affects what actually reaches your dog. If joint support specifically is what brought you here, The Best Joint Supplements for Senior Dogs applies these same verification questions to real products.

A supplement, certified or not, still supports wellness rather than replacing medicine — that’s true regardless of which label passed which audit. If your dog’s mobility, appetite, or energy is genuinely changing, that’s a veterinary visit, not a label-reading exercise.

The bottom line

AAFCO gives the industry a shared vocabulary and a set of model standards states can borrow. FDA decides, with real legal consequences, whether a product’s claims keep it in the food lane or push it into drug territory it hasn’t earned. Neither one pre-approves what’s in the bottle. NASC certification is the closest thing to independent verification currently available, and it costs more for a reason. Owners weighing a cheaper, uncertified option against a pricier, certified one aren’t choosing between two equally unregulated products — they’re choosing between a documented paper trail and a company’s word. I’d rather owners make that choice knowingly than assume “AAFCO compliant” on a bag means someone already checked.