Sodium carboxymethylcellulose (cellulose gum)

What this is

Cellulose gum is widely permitted as a food additive, but it has a mixed risk profile: traditional toxicology reviews are reassuring, while newer gut-microbiome research adds some uncertainty. JECFA assigned a group ADI not specified for modified celluloses including sodium carboxymethyl cellulose, and FDA lists sodium carboxymethylcellulose as GRAS when used according to good manufacturing practice. EFSA's 2018 re-evaluation found no need for a numerical ADI and no safety concern at reported uses, while noting incomplete data for some endpoints. The main policy change is narrow: the EU is withdrawing authorization for E 466 in specific infant and young-child medical-food categories and related nutrient preparations from 2027 because infant-use safety data were inadequate, not because E 466 was broadly found unsafe in general foods. A small controlled human study found 15 g/day CMC for 11 days perturbed gut microbiota and modestly increased post-meal abdominal discomfort.

Safety Review

The critical endpoints experts review in safety assessments. This is not a prediction of harm.

JECFA and EFSA-style reviews treat CMC/cellulose gum as low systemic-toxicity, with no genotoxicity, carcinogenicity, reproductive, or developmental signal in reviewed data. The biological concern is gastrointestinal rather than systemic: a small 11-day RCT at 15 g/day reported microbiome perturbation and modest post-meal discomfort, and EU action reflects infant-use data gaps and contaminant-specification tightening.