Is Carboxymethylcellulose safe?

It is listed as Low / Limited Concern. Primary concerns include Gastrointestinal, Inflammation.

Low / Limited Concern

Carboxymethylcellulose

Emulsifier/Thickener

GastrointestinalInflammation

Description

Carboxymethylcellulose, often listed as Cellulose Gum (E466), is a common food additive derived from plant cellulose, such as wood pulp. It has no nutritional value and is used as a thickener, stabilizer, and emulsifier to improve the texture and consistency of many processed foods. In fast food, it is frequently found in sauces, dressings, shakes, and baked goods to provide a creamy mouthfeel, prevent ingredient separation, and control ice crystal formation in frozen desserts . While major global regulators have long considered it safe, recent scientific studies have raised concerns about its potential to negatively affect gut health by altering intestinal bacteria.

Learn More Dossier

Aliases / Common Names: Sodium carboxymethyl cellulose, Cellulose Gum, Sodium CMC, Carmellose, E466, INS 466. Regulatory Status & Exposure: Major global bodies, including the U.S. FDA (GRAS status) and WHO/JECFA (ADI "Not Specified"), consider CMC safe based on evidence that it is not absorbed by the body. An EFSA re-evaluation in 2018 found no safety concern at current use levels . This traditional safety assessment is now challenged by research focusing on the gut microbiome. A pivotal 2021 human trial used a dose of 15 g/day, a high but potentially achievable exposure for individuals with diets rich in processed foods. Technical Evidence: The foundation of CMC's safety status—that it is inert because it is unabsorbed—is contradicted by recent findings. Animal studies since 2015 show CMC can disrupt the gut's protective mucus layer, alter the microbiome, and promote low-grade inflammation and metabolic syndrome. These concerns were elevated by a 2021 human controlled-feeding study where healthy volunteers consuming CMC experienced altered gut bacteria, a depletion of beneficial metabolites (e.g., short-chain fatty acids), and, in some individuals, bacterial encroachment into the gut lining—a hallmark of inflammatory disease . Furthermore, a large 2023 cohort study associated higher CMC intake with an increased risk of cardiovascular disease. Fast-Food Context: CMC is used to thicken sauces (McDonald's Tangy BBQ Sauce), prevent ice crystals in shakes (Burger King soft serve), and bind breadings (McDonald's Fish Filet Patty). Fast-food meals often contain a "cocktail" of multiple emulsifiers and thickeners (e.g., polysorbate 80, carrageenan, xanthan gum), whose combined effects on the gut microbiome are unstudied. Sensitive Populations / Notes: Individuals with Inflammatory Bowel Disease (IBD) or a predisposition to gut inflammation may be particularly susceptible to CMC's effects. Safety data for infants under 16 weeks of age is lacking, a data gap noted by EFSA.

Regulatory status

United States

Allowed Food (human consumption); GRAS listing under GMP. Basis: 21 CFR 182.1745 Source

European Union

Allowed E466 authorized in multiple food categories (category-specific conditions apply). Basis: Efsa Opinion Source

International

Allowed international food standards GSFA Table 3 (GMP) and additional category notes. Basis: Jecfa Evaluated Source

JECFA

Allowed Food additive specifications and toxicological position (ADI not specified). Basis: Jecfa Evaluated Source

Canada

Allowed Authorized in specified foods per incorporated-by-reference list (dated 2025-10-20). Basis: Other Source

Australia

Allowed Permitted in multiple processed foods (GMP), per FSANZ documentation and Code framework. Basis: Jecfa Evaluated Source

Registry review date: 2026-02-19

State policy updates

California (US)

Not Applicable Not regulated by this act (AB 418). Effective: 2027-01-01 Compliance: 2027-01-01 Source

Policy timeline

2023-02-02 — AB 418 introduced (California Food Safety Act) — CMC not identified as regulated substance in chaptered law. (California (US))
2023-10-07 — AB 418 chaptered (Chapter 328, Statutes of 2023) — bans 4 named substances; CMC not included. (California (US))
2027-01-01 — AB 418 compliance date for prohibited substances (not applicable to CMC). (California (US))

Research Evidence Snapshot

ACUTE SENSITIVITY HAZARD

Confidence: Medium

Low

Rare hypersensitivity reports exist primarily for medical/injectable contexts; food allergy signal appears uncommon in reviewed sources.

CHRONIC HEALTH EVIDENCE DIRECTION

Confidence: Low

Mixed/heterogeneous

Regulators conclude low toxicity at permitted uses, while emerging microbiome-focused evidence (short-term high-dose RCT; animal/mechanistic studies) and some observational associations suggest potential effects in some contexts.

EVIDENCE STRENGTH

Confidence: Medium

Limited

Extensive toxicology database supports low systemic toxicity; human causal evidence at typical dietary exposure remains limited (few RCTs; mostly short-term/high-dose).

REGULATORY POSTURE (U.S.)

Confidence: High

Authorized/Permitted

Listed in 21 CFR §182.1745 as GRAS when used under GMP.

REGULATORY DIVERGENCE

Confidence: Medium

Moderate

Broad allowance in US/international food standards/EU with GMP/common authorization; additional scrutiny and category-specific caution in infant/FSMP contexts in EU.

HEALTH-BASED GUIDANCE AVAILABILITY

Confidence: High

Established

ADI 'not specified' (JECFA) and EFSA 'no numerical ADI needed' conclusions exist.

EXPOSURE CERTAINTY

Confidence: Medium

Low

Food concentrations are rarely public (especially for restaurant foods); exposure assessments depend on assumptions and incomplete use-level reporting.

DATA RECENCY & STABILITY

Confidence: Medium

Evolving

Core regulatory status is stable; microbiome-focused research and some policy actions in sensitive categories continue to develop.

Found in these Restaurants

We found this ingredient in menu items at the following chains:

Dunkin'

IHOP

Taco Bell

Burger King

Wendy's

McDonald's

Arby's

Chick-fil-A

Starbucks

In-N-Out Burger

Kentucky Fried Chicken

1 items ›

Methodology

We assign the Low / Limited Concern tier using published research, regulatory guidance, and PRūF’s additive taxonomy. Restaurant usage is derived from public ingredient disclosures and mapped to menu items where this additive appears.

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Regulatory context

Learn how this additive is treated across different regulatory frameworks and why mixture effects can matter.

Regulatory frameworks overview Read analysis →

Scientific Sources & References

About this Audit

Data sourced from publicly available nutrition guides and ingredient lists as of 2026-03-04. Percentages represent the frequency of an ingredient's appearance across standard menu items, not the quantity within a specific item. Regional availability and supplier formulations may vary.

PRūF is an independent educational tool and is not affiliated with, endorsed by, or connected to any restaurant chain mentioned. All trademarks belong to their respective owners.

Carboxymethylcellulose

Description

Learn More Dossier

Regulatory status

State policy updates

Policy timeline

Research Evidence Snapshot

Found in these Restaurants

Methodology

Related questions and pages

Regulatory context

Scientific Sources & References

About this Audit

Scan your food for additives of concern