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GRAS Notification Process for Ingredients: 2026 Guide (Abbreviated)
Last Updated: October 24, 2026
Quick Summary
GRAS notification is voluntary: a company compiles safety evidence and asks the FDA not to object, and animal food ingredients under 21 CFR 570 can rely on a self-determined conclusion without ever filing.
- Self-determined GRAS is faster and cheaper, but leaves you defending the conclusion alone if challenged.
- A complete notice under 21 CFR 570 covers identity, manufacturing process, specifications, intended use, and safety basis.
- Calculate exposure by multiplying inclusion rate by daily feed intake, then dividing by body weight.
- Plan for at least one question-and-response cycle before you file.
- A no-questions letter is not an approval and creates no legal status.
Table of Contents
- How the GRAS Notification Process for Ingredients Works
- Animal Food GRAS Notice Requirements Under 21 CFR 570
- GRAS Notice Dossier Checklist and Sample Structure
- Scientific Evidence and Expert Consensus for a GRAS Determination
- How to Calculate Dietary Exposure and Estimated Intake
- GRAS Notice Examples for Feed Ingredients
- GRAS Notification Response Timeline and FDA Outcomes
- Frequently Asked Questions
How the GRAS Notification Process for Ingredients Works
This guide from Seven Hills Regulatory Services, LLC covers animal food ingredients under 21 CFR 570, where GRAS status is a legal conclusion, not an FDA certificate, so review stays voluntary.
Self-Determined GRAS vs. Voluntary FDA Notification
Self-determined GRAS documents the safety conclusion internally; voluntary notification submits it to the FDA and ends with a response letter you can share with buyers.
Where Animal Food Fits Under 21 CFR 570
Animal food ingredients follow a separate track from human food under 21 CFR 570. A substance for pets or livestock is an animal food ingredient, a food additive, or a drug, with no supplement category for animals (FDA).
Animal Food GRAS Notice Requirements Under 21 CFR 570
An animal food GRAS notice under 21 CFR 570 must establish identity, manufacturing process, specifications, intended use, and safety basis.
Ingredient Identity and Chemical Characterization
Identity is the precise description of the substance: chemical name, formula, CAS number, and source. Characterization covers purity and lot-to-lot variability, where dossiers fail first.
Manufacturing Process and Specifications
The manufacturing section describes how the substance is made: raw materials, process conditions, purification, and controls, tied to the safety conclusion.
GRAS Notice Dossier Checklist and Sample Structure
A GRAS dossier follows the parts the FDA expects, so build it in order to avoid restructuring later.
Use this checklist as your build guide:
- Cover letter and administrative information
- Part 1: Signed statement of the GRAS conclusion
- Part 2: Identity and chemical characterization
Sample structure: open with a brief summary of your conclusion and strongest evidence, then the parts above in order.
Scientific Evidence and Expert Consensus for a GRAS Determination
A GRAS determination needs sufficient scientific evidence and expert consensus that it supports safety under the intended use.
The evidence base combines toxicological, absorption, and feeding studies, with target-species tolerance data mattering most for animal food ingredients.
Expert consensus comes from qualified experts who independently review the evidence and sign a documented conclusion.
How to Calculate Dietary Exposure and Estimated Intake
Dietary exposure for an animal food ingredient is calculated by multiplying the inclusion rate in the complete feed by the animal's daily feed intake, then dividing by body weight to get intake per kilogram per day.
The assumptions, not the math, decide success or failure, so every input needs a documented, defensible source.
The Four Inputs You Must Document
- Inclusion rate. Maximum use level as a percentage of feed, by species and stage.
- Daily feed intake. Published intake value for the species and stage, with a cited source.
- Body weight. Average weight for the production stage, not mature weight.
- Duration and life stage. Note whether exposure is short-term or long-term.
A Worked Example
Suppose a feed additive is proposed at 0.10% inclusion in the complete diet for broiler chickens, which eat roughly 0.15 kg of feed per day and weigh roughly 1.5 kg at that stage. The animal's intake of the substance is:
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- 0.10% of 0.15 kg = 0.00015 kg of substance per day = 150 mg per day
- 150 mg ÷ 1.5 kg body weight = 100 mg per kg body weight per day
That figure, 100 mg/kg bw/day, compares against the no-observed-adverse-effect level (NOAEL) from toxicology studies. If the NOAEL is 1,000 mg/kg bw/day, the margin of exposure is 10x.
Aggregate Exposure Across Species and Categories
Calculate exposure separately for each target species, including the highest intake-to-weight ratio, and address residue carryover into meat, milk, or eggs for food-producing animals.
Common Calculation Errors
- Using premix level, not complete diet: inflates or hides exposure.
- Using mature weight for a growing animal: understates exposure per kilogram.
- Ignoring the highest-intake species: invites a reviewer question.
GRAS Notice Examples for Feed Ingredients
The strongest GRAS notices state exact inclusion rates by species and stage, cite feeding studies at or above the proposed use level, and address carryover where relevant.
GRAS Notification Response Timeline and FDA Outcomes
The response timeline runs on a defined clock once the FDA files your notice, but what matters most is what each letter means and your options afterward.
Outcome 1: No Questions Letter
A no questions letter is the favorable outcome most filers seek: the FDA reviewed the notice and did not object.
Next steps: Keep the notice on file, reference the notice number with customers, and monitor for changes in use.
Outcome 2: Letter Identifying Specific Concerns
The letter flags a specific gap, such as the exposure calculation, toxicology database, or expert consensus documentation.
Next steps: Respond with more data, amend if the gap is documentation, or withdraw and refile if the gap is data.
Outcome 3: Insufficient Basis Letter
This is the most serious outcome: FDA does not agree the evidence supports the GRAS conclusion as submitted.
Next steps: Withdraw and refile with a stronger package, or proceed self-determined if you can defend the conclusion without agency review.
Withdrawal Is a Strategic Option, Not a Failure
Withdrawal is often right when data needs strengthening: it does not prejudice a later filing and stops the clock before an unfavorable letter.
What the Timeline Actually Looks Like
Preparation, characterization data, tolerance studies, and the expert panel, usually takes longer than the review itself, so build buffer for at least one question-and-response cycle.
Our team at Seven Hills Regulatory Services, LLC, toxicologists, animal nutritionists, and former FDA scientists, reviews packages against real reviewer questions.
Frequently Asked Questions
What is the GRAS notification process for animal food ingredients?
A notice under 21 CFR 570 covers identity, manufacturing, use levels, exposure, and safety data, and is voluntary but creates a public FDA record.
How long does FDA take to respond to a GRAS notice?
FDA's 180-day review clock starts once it files your notice, though questions often pause and extend it.
Can a company market an animal food ingredient after submitting a GRAS notice?
Yes: GRAS status rests on your self-determination, not FDA's response, though many buyers ask for the no-questions letter.
What scientific evidence supports GRAS status for an animal food ingredient?
Evidence typically includes toxicological studies, target-animal safety data, common use in feed, and a dietary exposure assessment, with strength mattering more than volume.
What is the difference between a GRAS notice and a food additive petition for animal food?
A food additive petition under 21 CFR 570 requests formal premarket approval, while a GRAS notice is voluntary and self-determined with no approval regulation.
What should an animal food GRAS notice include?
A complete notice covers identity and characterization, manufacturing, conditions of use, an intake assessment, and safety evidence with expert consensus.
