Emily Whitest, Research Fellow 

If you’ve ever read an ingredient list on the back of a bottle of salad dressing or a box of crackers and felt confused, you are not alone. The regulatory world of food ingredients is a complex web of federal regulations and statutes. Understanding how the FDA categorizes these food ingredients is a useful starting point. It helps explain not only what is in food, but also how these ingredients are evaluated before they reach consumers.

Under the Federal Food, Drug, and Cosmetic Act of 1938 (“FDCA”), there are four legal classifications of food ingredients: 1) Food Additives, 2) Generally Recognized as Safe (“GRAS”), 3) Color Additives, and 4) Prior-sanctioned Substances.

1) Food Additives

The FD&C defines a food additive broadly. Under 21 U.S.C. § 321(s), it includes “any substance the intended use of which results or may reasonably be expected to result, directly or indirectly, in its becoming a component or otherwise affecting the characteristics of any food.” This means food additives are not just ingredients added into food during cooking. It also includes substances used in producing, manufacturing, packaging, processing, preparing, treating, transporting, or holding food. Since food additives are defined so broadly, most food ingredients fall into this category unless they qualify for an exemption, such as GRAS or prior-sanctioned substance (to be covered in sections below).

Types of Food Additives

The FDA further organizes food additives into three groups based on how the substance interacts with the food product. These categories include direct food additives, secondary food additives, and indirect food additives. First, direct food additives are food ingredients that are added for a specific functional purpose. For example, aspartame is often found in diet sodas as a sweetener and xanthan gum is often found in salad dressing as a thickener and stabilizer. These ingredients are part of the final product and show up on the label. 21 CFR Part 172.

Next, secondary food additives are used during the manufacturing or processing of the food product but may not remain in meaningful amounts in the final product. They are not required to be labeled on the back of the food product. An example of a secondary food additive is hexane in hops extract as a residue from the extraction of hops. 21 CFR Part 173. Lastly, indirect food additives are those that encounter a food product through its food packaging materials, coatings inside cans, or adhesives used in containers. They are not added to the ingredient list on the back of the food product, but they are still regulated by the FDA because they can affect food safety. 21 CFR Part 174 -178.

Food Additive Approval Process

Under the FD&C Act, direct food additives must be preapproved by the FDA before they can be used in a commercial food product. This process is referred to as the Food Additive Petition, and is regulated under 21 CFR Part 171. In order to get a food additive approved, a food manufacturer must first submit the petition providing evidence showing the ingredient is safe in the ways it will be used and with the intended levels of use in the food product. Then, the FDA will review the petition as well as other relevant information to determine if the available information demonstrates that the food additive is safe for use under the manufacturer’s proposed conditions. The petition process for a food additive requires a scientific determination that there is a reasonable certainty the food additive will cause no harm to the consumer. Once the food additive is approved, the agency then issues a regulation that authorizes the food additive to be used in foods. The FDA also updates a public inventory of food additives petitions. The inventory includes petitions that are actively being reviewed and those that were filed but are not active due to deficiencies found during the review of the petition.

Indirect food additives are not evaluated or approved by FDA through a Food Additive Petition. Instead, these substances are classified as “food contact substances.” Not all food contact substances are considered food additives, but the ones that are must be authorized by the FDA for its intended use before it can be marketed in the US. This process is called Food Contact Substance Notification System and will require the indirect food additive’s manufacturer to submit information supporting the substance’s safety. 21 CFR § 170.100. If the FDA does not object to the substance’s use within 120 days, then the manufacturer may legally market the substance for the uses identified in the notification. Additionally, some indirect food additives may be approved through a process called Threshold of Regulation. This process found in 21 CFR § 170.39 covers indirect food additives that are “exempted from regulation as a food additive because it becomes a component of food at levels that are below the threshold of regulation.”

Secondary food additives may be approved through the traditional food additive petition process, or per the FDA, some might “meet the definition of a food contact substance” and go through the Food Contact Substance Notification Program.

2) Generally Recognized as Safe (“GRAS”)

Some food ingredients are exempt from the food additive petition process because they are regulated under the “GRAS” pathway. “Generally recognized as safe” (GRAS) was introduced in the 1958 Food Additives Amendment to the FD&C Act. This amendment was made when Congress recognized that some food ingredients did not need a formal premarket review and approval by the FDA because their safety was already established, for example, ingredients like table salt and vinegar. In 1958, the FDA published the first GRAS List. The current GRAS list is codified in 21 CFR Part 182; 184; 186.

Pathways to GRAS

A substance can achieve GRAS status through two legal avenues: 1) History of Use and 2) Scientific Consensus. 21 CFR § 170.30. If an ingredient was commonly used in food prior to January 1, 1958, and it had a long record of safe consumption, it may qualify as GRAS. Common examples include vinegar and vegetable oil. On the other hand, an ingredient may be GRAS if qualified experts agree, based on analyzing publicly available scientific evidence, that it is safe under its intended use. This is the process largely used today.

Like food additives, GRAS substances are classified by how they interact with food. Direct GRAS substances are those that are intentionally added to a food product and are generally recognized as safe for that use. A list of direct GRAS substances can be found at 21 CFR Part 184. Examples include vinegar (21 CFR § 184.1005) and corn syrup (21 CFR § 184.1865). Direct GRAS substances are part of the final food product and appear on the label.  Similar to indirect food additives, indirect GRAS substances are substances that are not directly added to the food product but may come in contact with it. A list of indirect GRAS substances can be found at 21 CFR Part 186. Examples include substances used in food packaging, processing equipment, and on food contact surfaces. Indirect GRAS substances are not listed on the ingredient label, but they are still evaluated for safety of use under the GRAS framework because they may migrate into food through contact materials.

1997-Present – GRAS Notification System

In 1997, the FDA introduced the voluntary GRAS notification program, which allowed food manufacturers to notify the FDA of their individual GRAS determinations. 21 CFR § 170 Subpart E.  This process shifted the burden of safety determination onto the manufacturer, with the FDA acting as a secondary reviewer. The FDA would then evaluate whether the GRAS notice provides sound science and publicly available data that support an ingredient being GRAS. If the FDA needs no additional information, they will send the company a “no questions” letter. The FDA is currently reevaluating aspects of the GRAS framework, and is expected to publish rulemaking soon.

3) Color Additives

Color additives are distinguished as a separate category under the FDCA and are subject to their own regulatory framework. A color additive is any dye, pigment, or other substance that can impart color when added to a food.  Color additives are divided into two categories, synthetic and naturally occurring, and their classification will determine if they are required to be certified by the FDA or not.

Synthetic color additives must be tested and certified by the FDA on a batch by batch basis. See 21 CFR Part 74. Common examples include FD&C Blue No. 1 (21 CFR § 74.101) and FD&C Red No. 40 (21 CFR § 74.340). There are seven certified color additives for use in foods, and they are called “FD&C” color additives. You may also see these additives in other countries under different names; for example, FD&C Red No. 40 is called Allura Red AC or E129 in the European Union. Certification ensures that each batch meets FDA standards for identity, purity, and composition.

Naturally occurring color additives are derived from natural sources and are exempt from batch certification.  However, they still need to be approved for a new use by the FDA before used in foods. Examples of exempt color additives include beet powder (21 CFR § 73.40) and turmeric (21 CFR § 73.600).

Unlike the many other food ingredients, color additives can never qualify as GRAS. All color additives must instead go through a specific approval process before they can be used in a food product. See 21 USC § 379e. To obtain approval, manufacturers must submit a color additive petition to the FDA which demonstrates that the additive is safe for its intended use. The petition must include data on its composition, stability, and potential exposure levels. After submission, the FDA will evaluate  scientific evidence to determine whether the additive meets the statutory safety standard.  If it does, FDA will issue a regulation authorizing its use. To learn more about color additives, and the FDA’s current actions to limit the use of synthetic dyes, click here to read NALC article “FDA Announces Plan to ‘Phase Out’ Synthetic Dyes.”

4) Prior-Sanctioned Substances

Prior-sanctioned substances are an often overlooked category of food ingredients within the FDA’s regulation. They represent a transitional moment in food law, where Congress shifted to a more formal approach for approving food additives but still wanted to recognize earlier approvals. Prior-sanctioned substances are those that were explicitly approved for use in food by either the FDA or U.S. Department of Agriculture (“USDA”) prior to the 1958 Food Additives Amendment. Prior-sanctioned substances are not considered to be food additives because they fall within an exception to the statutory definition. 21 U.SC § 321(s).

The 1958 Cutoff

When Congress enacted the 1958 Food Additives Amendment, it created the current premarket approval process for food additives. Congress also acknowledged when making the amendment that some food substances had already been approved for specific uses. Instead of making those food substances go through the new approval process, the amendment allowed them to continue to be used in their originally approved use. As a result, only substances that were approved prior to 1958 can qualify as a prior-sanctioned substance. 21 CFR Part 181.

Substances Prohibited from Use in Human Food

There is technically a fifth category of food additives as well, which are substances prohibited from use in human foods. 21 CFR Part 189. Unlike other food additives, these substances are not permitted under any circumstances in food because they have been determined to be unsafe. This category includes substances that have been shown to pose health risks, were previously used but later restricted or banned, and do not meet the safety standard under the FD&C act. Some examples include calamus (formerly used in flavoring and banned due to demonstration of carcinogenic effects long term) and thiourea (formerly used to prevent browning in fruit and banned due to carcinogenic effect on thyroid and liver). In some cases, the substance was once allowed but was later prohibited as scientific evidence and understanding evolved.

FDA Food Ingredient Categories in a “JIFFY”

USDA’s Role in Regulating Food Ingredients

While the FDA regulates most food ingredients, the United States Department of Agriculture (“USDA”) plays a similar role for meat, poultry, and certain egg products through its Food Safety and Inspection Service (“FSIS”). Unlike the FDA’s premarket approval framework for food and color additives, the USDA does not maintain a separate ingredient approval system. FSIS evaluates ingredients as part of its oversight of product formulation, labeling, and safety. FSIS relies on FDA determinations, such as food additive approvals or GRAS status, when assessing whether an ingredient is permissible. The agencies function as a coordinated regulatory scheme where the FDA assesses ingredient safety, and the USDA oversees their application in specific categories of food products. To learn more about FSIS and food additives, click here.

Conclusion

The FDA sorts food ingredients into several categories including food additives, color additives, GRAS, and prior-sanctioned substances. The classification of a food ingredient is key to understanding how its safety was determined by the agency, and whether its presence in food appears on the food’s label. Food ingredients remain a frequent topic in political discussions. For recent examples of this debate, click here to read NALC articles on the subject.

For a complete list of food ingredients maintained by the FDA, click here.

For a Q&A of color additives, click here.

For an FDA chart explaining food ingredients, click here.