What "Natural Flavors" Actually Mean (And What the Label Legally Leaves Out)

What does "natural flavor" legally mean?

"Natural flavor" is one of the few front-of-ingredient-list phrases that has a real federal definition — and it's narrower than most people assume. Under 21 CFR 101.22(a)(3), the FDA defines natural flavor as:

"The essential oil, oleoresin, essence or extractive, protein hydrolysate, distillate, or any product of roasting, heating or enzymolysis, which contains the flavoring constituents derived from a spice, fruit or fruit juice, vegetable or vegetable juice, edible yeast, herb, bark, bud, root, leaf or similar plant material, meat, seafood, poultry, eggs, dairy products, or fermentation products thereof, whose significant function in food is flavoring rather than nutritional."

Read that last clause twice: whose significant function in food is flavoring rather than nutritional. That's the whole job description. A natural flavor exists to make food taste like something. The definition is about where the flavoring substance comes from — a plant or an animal — and nothing else. It is not a health claim. It says nothing about how clean, how whole, or how minimally processed the result is.

Is "natural" flavor any better than "artificial" flavor?

Legally, the only difference between the two is the source of the flavoring substance — not safety, not chemistry, not processing. Right next to the natural-flavor definition, 21 CFR 101.22(a)(1) defines artificial flavor as:

"Any substance, the function of which is to impart flavor, which is not derived from a spice, fruit or fruit juice, vegetable or vegetable juice, edible yeast, herb, bark, bud, root, leaf or similar plant material, meat, fish, poultry, eggs, dairy products, or fermentation products thereof."

Put the two side by side and the entire distinction collapses to one word: derived. A natural flavor's starting material has to trace back to a plant or animal. An artificial flavor's doesn't. That's it. Both are typically isolated, concentrated, and purified in a lab. The Environmental Working Group makes the same point in plain language — the source is "the sole difference," and both kinds can be complex mixtures.

So when a label leans on "natural flavors" to imply wholesome, it's borrowing a halo the regulation never granted. "Natural" here is a sourcing rule, not a quality grade.

What can a single "natural flavors" line actually contain?

A lot more than one ingredient — because the rules let a whole mixture collapse into a single collective term. Under 21 CFR 101.22(h)(1):

"Spice, natural flavor, and artificial flavor may be declared as 'spice', 'natural flavor', or 'artificial flavor', or any combination thereof, as the case may be."

That one sentence is why a flavor compound built from dozens of components shows up on your label as two words. The flavor industry treats the precise recipe as a trade secret, and the collective-declaration rule lets them keep it that way. You see the category; you don't see the constituents.

There's a second mechanism stacked on top. Flavor compounds aren't shipped as pure essence — they ride in carriers and solvents (think a liquid base to dissolve and stabilize the flavoring), and they can carry preservatives or emulsifiers. Many of those supporting substances never appear on your label at all, because of 21 CFR 101.100(a)(3), which exempts:

"Incidental additives that are present in a food at insignificant levels and do not have any technical or functional effect in that food."

The regulation spells out the categories that qualify — substances that come along as part of another ingredient where they once served a purpose (101.100(a)(3)(i)), processing aids (101.100(a)(3)(ii)), and substances that migrate from equipment or packaging (101.100(a)(3)(iii)). If a solvent or stabilizer inside a flavor compound is judged to be at an "insignificant level" with "no technical or functional effect" in the finished food, the law does not require it on the ingredient list.

So the honest list of what can hide behind "natural flavors" — only the categories the regulations actually describe — looks like this:

1. Multiple flavoring constituents, declared collectively under 101.22(h)(1) rather than itemized.
2. Carriers and solvents used to dissolve or deliver the flavor compound.
3. Preservatives or emulsifiers built into the compound.
4. Incidental additives exempt from declaration under 101.100(a)(3).
5. The source itself — the plant or animal the flavor was derived from is not disclosed.

Notice what's not on that list: a named villain. We're not claiming a specific chemical is lurking in your seltzer. We're saying the label structure permits a mixture, and you can't see inside it.

Can "natural flavors" legally hide an allergen?

No — and this is the most important fairness point in the whole conversation. A flavor compound cannot legally bury one of the 9 major food allergens. Under FD&C Act §403(w)(4), codified at 21 U.S.C. §343(w):

"Notwithstanding subsection (g), (i), or (k), or any other law, a flavoring, coloring, or incidental additive that is, or that bears or contains, a major food allergen shall be subject to the labeling requirements of this subsection."

In plain terms: the collective-declaration and incidental-additive loopholes do not override allergen law. If a natural flavor carries milk, egg, fish, crustacean shellfish, tree nuts, peanuts, wheat, soybeans, or sesame, that allergen has to be declared. The Food Allergen Labeling and Consumer Protection Act (FALCPA) established the original eight; the FASTER Act added sesame as the ninth major allergen, effective January 1, 2023.

The FDA's guidance on sesame is explicit that the allergen must surface even when it's used in something otherwise named collectively — for example, "flavor (sesame)" or "spice (sesame)." So the disclosure gap in "natural flavors" is real, but it has a hard floor: it can obscure the recipe, the carriers, and the source — it cannot obscure a major allergen.

So is the source ever disclosed?

Almost never — and that's the gap that matters most for real-world decisions. The natural-flavor definition requires the flavoring to come from a plant or animal, but it does not require the label to tell you which one. "Natural flavors" on a vanilla oat bar could be derived from a plant, from a dairy product, or from a fermentation process — and the line reads identically in all three cases.

That ambiguity is where the real friction lives, and it's not a health question — it's an identity question:

• Vegans and vegetarians can't tell from "natural flavors" alone whether the source was animal-derived.
• Kosher and halal observers face the same blind spot on species and source.
• People avoiding a specific food for non-allergen reasons (a sensitivity that isn't one of the nine majors) get no signal at all.

For these readers, "natural flavors" isn't reassuring or alarming — it's simply silent. The label told you the category of the flavoring substance and withheld the identity. That's legal. It's also exactly the kind of thing you'd want to know before you bought it.

What should you actually do about "natural flavors"?

Treat it as a known unknown, not an alarm — and let the rest of the panel carry the weight. "Natural flavor" tells you a flavoring came from a plant or animal and is doing a flavoring job. It does not tell you the recipe, the carriers, the processing, or the source. That's a transparency limit baked into 21 CFR 101.22 and 101.100, not evidence of anything sinister.

Our read: don't fear the phrase, but don't let it earn a product points it didn't pay for. A long ingredient list that ends in "natural flavors" is more processed than whole food, by definition — the flavor had to be added because the food didn't taste like enough on its own. If you have an allergen, the law already has your back inside that line. If you're vegan, kosher, halal, or avoiding a specific source, "natural flavors" is your cue to check the brand directly, because the label won't answer the question for you.

The phrase isn't a poison. It's a curtain. Knowing it's a curtain is the whole skill.

Sources

1. Cornell Legal Information Institute. 21 CFR 101.22 — Foods; labeling of spices, flavorings, colorings and chemical preservatives. law.cornell.edu/cfr/text/21/101.22
2. Cornell Legal Information Institute. 21 CFR 101.100 — Foods; exemptions from labeling. law.cornell.edu/cfr/text/21/101.100
3. U.S. Code. 21 U.S.C. §343(w) (FD&C Act §403) — Misbranded food; major food allergen labeling. govinfo.gov
4. FDA. The FASTER Act: Sesame Is the Ninth Major Food Allergen. fda.gov
5. Michigan State University, Institute for Food Laws and Regulations. The FASTER Act — Sesame as Major Food Allergen. canr.msu.edu
6. Environmental Working Group. Natural and artificial flavor: What's the difference? ewg.org

Keep reading

• AdditivesRed Dye 40 Isn't Banned. Here's What's Actually Happening — and the Full Brand Hit List.9 min read
• AdditivesIs Impossible Meat Vegan? The Heme and the Animal-Testing Asterisk9 min read
• Gluten-FreeWhy "Naturally Gluten-Free" Oats Are a Label Trick8 min read