Disodium 5'-ribonucleotides

About

What it is and where it shows up.

Disodium 5'-ribonucleotides is a mixture of disodium inosinate (E631/IMP) and disodium guanylate (E627/GMP), both of which are naturally occurring nucleotides that serve as building blocks of RNA and DNA. It is used as a flavour enhancer (umami potentiator) in snack foods, instant noodles, soups, sauces, and seasonings, typically in combination with monosodium glutamate (MSG) to amplify savoury taste.

Safety summary

The regulatory and scientific consensus.

JECFA and the EU Scientific Committee for Food (SCF) have established no specific ADI for ribonucleotides, considering them safe at normal use levels; however, they are metabolised to purines and ultimately to uric acid, posing a clinically significant risk for individuals with gout or hyperuricaemia. EFSA launched a formal re-evaluation of ribonucleotides (E626–E635) in 2023, with data submission closed in March 2024, meaning the safety assessment is still pending. Aspirin-sensitive individuals have reported pseudoallergic reactions (urticaria, skin rashes) to E635, and it is not recommended for infants who lack the metabolic capacity to efficiently process purines.

Regulatory landscape

What food-safety regulators have decided.

Jurisdiction	Status	Note
FSANZ (Food Standards Australia New Zealand) (Australia)	Approved	Permitted as INS 635 under the Australia New Zealand Food Standards Code (Schedule 8) as a flavour enhancer. Quantum satis or category-specific maxima apply.source
EFSA (European Food Safety Authority) (European Union)	Approved	Permitted under Regulation (EC) No 1333/2008 as a flavour enhancer (E635) at quantum satis in many food categories and up to 500 mg/kg in others (as part of ribonucleotides group E626–E635). Formally under re-evaluation by EFSA since 2023 (call for data closed March 2024); status remains approved pending re-evaluation outcome.source
Food Standards Agency (FSA) / Food Standards Scotland (FSS) (United Kingdom)	Approved	Authorised under Assimilated Regulation (EC) No 1333/2008, Annex III, as part of the ribonucleotides group (E626–E635). Conditions of use mirror the pre-Brexit EU framework.source
FSSAI (Food Safety and Standards Authority of India) (India)	Approved	Permitted as a flavour enhancer (INS 635) under the Food Safety and Standards (Food Products Standards and Food Additives) Regulations, 2011. Specific maximum permitted levels depend on food category; no ADI established.source

Who should approach with care

Whose guidance would steer them away.

Gout — E635 is metabolised to purines and then to uric acid; high purine intake is a well-established trigger for gout flares and worsening of hyperuricaemia.

Infants — Infants have immature purine metabolism and cannot efficiently process nucleotides at the levels provided by E635; it is excluded from infant food formulations under EU and Codex standards.

Children — Young children have a higher relative exposure compared to adults (mg/kg body weight basis) and regulators recommend caution with flavour enhancers in foods targeted at children.

Kidney Disease — Impaired renal function reduces uric acid clearance; increased purine load from E635 metabolism may exacerbate urate accumulation in patients with chronic kidney disease.

Other — Aspirin-sensitive individuals (salicylate intolerance) have reported pseudoallergic reactions including urticaria and skin rashes linked to E635, likely via a non-IgE-mediated mechanism.

Research citations

The sources behind this verdict.

1WHO. JECFA Compendium of Food Additive Specifications – Disodium 5′-ribonucleotides (INS 635). fao.org
2FAO. GSFA Online Food Additive Details – Disodium 5′-ribonucleotides (INS 635). fao.org
3EFSA. Call for data for the re-evaluation of ribonucleotides (E 626–635) as food additives, 2023. efsa.europa.eu
4other. Commission Implementing Regulation (EU) 2018/238 – Authorisation of disodium 5′-ribonucleotides, disodium 5′-guanylate and disodium 5′-inosinate as feed additives, 2018. eur-lex.europa.eu
5EFSA. Scientific Opinion on the safety and efficacy of disodium 5′-ribonucleotides, disodium 5′-guanylate, disodium 5′-inosinate for all animal species and categories, 2014. efsa.europa.eu

Independently researched5 citations