FDA Definition of Food: Statute, Scope, and Obligations

Under the Federal Food, Drug, and Cosmetic Act, the FDA definition of food covers three things: articles used for food or drink by humans or animals, chewing gum, and any component of such articles.¹ That definition sits at 21 U.S.C. § 321(f), and it is broader than most people expect. It turns on how a product is intended to be used, not on what the product physically is, which is why the same substance can be food in one bottle and something else entirely in the next.

What the Statute Actually Says

Section 201(f) of the FD&C Act breaks “food” into those three parts and stops there. No calorie threshold, no nutrition requirement, no exclusion for products that taste terrible or serve no dietary purpose. Chewing gum gets its own clause because it isn’t swallowed and would otherwise sit outside the “eating or drinking” language.

Intended use is what does the sorting. A sugar syrup sold as a pancake topping is food. The same syrup sold as a carrier for an industrial process is not. The FDA looks at labeling, advertising, and the surrounding context to determine what the manufacturer intends the product to be, and that determination controls which body of regulation applies.

Components: Why Ingredients Are Food Too

The third part of the definition — “articles used for components of any such article” — pulls raw ingredients into the regulatory framework even though nobody sits down to a bowl of them. Flour, preservatives, flavorings, emulsifiers, and processing aids all qualify as food. If a substance is intended to become part of a finished food product, the FDA regulates it as food.

That has direct consequences for anyone adding something new to the food supply. Any substance whose intended use results in it becoming a component of food is a “food additive” and needs FDA premarket approval, unless it fits one of the statute’s carve-outs.¹ The carve-outs in 21 U.S.C. § 321(s) are the reason most ingredients never see a formal approval process:

Substances generally recognized as safe (GRAS) by qualified experts, either through scientific evidence or, for pre-1958 ingredients, a history of common use.
Prior-sanctioned substances approved by the FDA or USDA before September 6, 1958.
Pesticide residues, which are regulated under separate pesticide statutes.
Color additives, which run through their own approval process.
New animal drugs.
Dietary supplement ingredients, which sit under DSHEA.

GRAS is the biggest of these in practice. A manufacturer can conclude on its own that a substance is GRAS and add it to food without ever notifying the FDA. The agency runs a voluntary notification program and can respond that it has no questions, that the notice is insufficient, or accept a withdrawal, but the notice itself is not required.²

How Food Differs from a Drug

The same product can be food or a drug depending entirely on how it is marketed. The Act defines a drug as any product intended to diagnose, cure, treat, or prevent disease, or any product (other than food) intended to affect the structure or function of the body.¹ The parenthetical “other than food” carries most of the weight. Food that naturally affects the body — coffee on the nervous system, fiber on digestion — doesn’t become a drug just because it has physiological effects.

The bright line is disease claims. Market chamomile tea as a relaxing beverage and it is food. Market that same tea as a treatment for anxiety disorder and the FDA will treat it as an unapproved drug regardless of what is in the bottle.¹

Health Claims That Keep a Product Classified as Food

Not every health-related statement turns food into a drug. The Act creates a safe harbor for authorized health claims made under Section 403(r): food carrying such a claim is not a drug solely because the label contains it.¹ Authorized health claims describe a relationship between a food or nutrient and reduced risk of disease, and they must be backed by significant scientific agreement and reviewed by the FDA before use. Examples include calcium and vitamin D and osteoporosis risk, soluble fiber and coronary heart disease risk, and folic acid and neural tube defect risk.³

The distinction is risk reduction versus treatment. “May reduce the risk of heart disease” keeps the product as food. “Treats heart disease” is a disease claim and makes it a drug.

Structure/function claims are the other safe category. Statements like “calcium builds strong bones” or “fiber maintains digestive regularity” describe effects on normal body function without referencing disease.⁴ Conventional foods can make these claims without notifying the FDA. Dietary supplements can too, but the manufacturer must notify the FDA within 30 days of first marketing the product with such a claim and must carry the boldface disclaimer that the statement has not been evaluated by the FDA and the product is not intended to diagnose, treat, cure, or prevent any disease.⁵

How Food Differs from a Cosmetic

The Act defines a cosmetic as a product intended to be applied to the human body for cleansing, beautifying, promoting attractiveness, or altering appearance.⁶ The split from food is route and purpose: food goes inside for nourishment or taste, cosmetics go on the outside for appearance. Products can straddle the line in narrow cases. A mouthwash marketed only for fresh breath reads as a cosmetic; the same product marketed for a nutritional or dietary purpose moves toward food. The FDA evaluates labeling and marketing to determine which framework applies.

Special Categories the Definition Sweeps In

Because “food” turns on intended use rather than composition, the definition pulls in several product types that carry their own rules on top of the general food framework.

Animal Food

The definition applies whether the product is intended for people or animals. Human food falls under 21 CFR Part 117 and animal food under 21 CFR Part 507, and safety judgments do not transfer between them. Propylene glycol, for example, is generally recognized as safe in human food but is prohibited in cat food.

Dietary Supplements

The Dietary Supplement Health and Education Act of 1994 defined dietary supplements as products intended to supplement the diet that contain one or more dietary ingredients — vitamins, minerals, herbs, amino acids, and concentrates or extracts of those substances. Supplements are legally food, not drugs, but the burden of proof flips: the FDA does not approve supplements before marketing, and to remove one from the market the agency must show the product is unsafe or adulterated.⁷ One narrow exception: a supplement containing a new dietary ingredient (one not sold in the United States before October 15, 1994) that hasn’t been present in the food supply in unaltered form requires a manufacturer notification to the FDA at least 75 days before marketing.⁸

Medical Foods

A medical food is formulated for the dietary management of a specific disease or condition with distinctive nutritional requirements established by medical evaluation, and it must be consumed under a physician’s supervision.⁹ Medical foods are not drugs and don’t go through drug approval, but they aren’t ordinary food either. They must be specially formulated and processed for patients whose conditions limit their ability to digest, absorb, or metabolize ordinary food, or who have medically determined nutrient requirements that diet alone cannot meet.¹⁰ The specialized formulas used in hospitals for tube feeding or for metabolic disorders like PKU are typical examples.

Infant Formula

Infant formula sits in a regulatory middle ground. The Act sets specific minimum and, in some cases, maximum levels for more than 29 nutrients that every infant formula must contain, and any formula that doesn’t meet those standards is automatically adulterated. Manufacturers must register with the FDA and submit required information at least 90 days before introducing a new infant formula, which is a premarket notification most food products never face.¹¹

What Classification as Food Obligates You to Do

Once a product is food, a set of labeling and safety duties comes with the classification. The one most consumers encounter is allergen labeling. Every FDA-regulated food label must specifically declare any of nine major food allergens present in the product: milk, eggs, fish, crustacean shellfish, tree nuts, peanuts, wheat, soybeans, and sesame. The first eight were set by the Food Allergen Labeling and Consumer Protection Act of 2004; sesame was added by the FASTER Act in 2021, taking effect January 1, 2023.¹² Tree nuts, fish, and crustacean shellfish must be declared by species — “almonds” rather than “tree nuts,” “shrimp” rather than “shellfish.” A food that fails to declare a major allergen is misbranded.¹³

The two concepts that carry the FDA’s enforcement authority over food are adulteration (food that is unsafe, contaminated, or fails required standards) and misbranding (food with false, misleading, or incomplete labeling). When the FDA finds either, its options run from warning letters and voluntary recalls to seizures, injunctions, and criminal prosecution, with civil and criminal penalties scaling with the severity of the violation and any intent to defraud.¹⁴¹⁵ Those penalties are the practical reason the classification question matters: knowing whether a product is food, a drug, a cosmetic, a supplement, or a medical food determines which rulebook the agency will hold you to.

1
Office of the Law Revision Counsel. 21 USC 321 – Definitions; Generally
2
U.S. Food and Drug Administration. About the GRAS Notification Program
3
U.S. Food and Drug Administration. Authorized Health Claims That Meet Significant Scientific Agreement
4
U.S. Food and Drug Administration. Structure/Function Claims
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U.S. Food and Drug Administration. Notifications for Structure/Function and Related Claims in Dietary Supplement Labeling
6
U.S. Food and Drug Administration. Cosmetics and U.S. Law
7
U.S. Food and Drug Administration. Dietary Supplements
8
Office of the Law Revision Counsel. 21 USC 350b – New Dietary Ingredients
9
Office of the Law Revision Counsel. 21 USC 360ee – Grants and Contracts for Development of Drugs for Rare Diseases or Conditions
10
U.S. Food and Drug Administration. Guidance for Industry: Frequently Asked Questions About Medical Foods – Third Edition
11
Office of the Law Revision Counsel. 21 USC 350a – Infant Formulas
12
U.S. Food and Drug Administration. Food Allergies
13
U.S. Food and Drug Administration. Questions and Answers Regarding Food Allergen Labeling (Edition 5)
14
U.S. Food and Drug Administration. Compliance and Enforcement (Food)
15
Office of the Law Revision Counsel. 21 USC 333 – Penalties