Disodium Diphosphate

About

What it is and where it shows up.

Disodium diphosphate (E450i) is an inorganic sodium salt of pyrophosphoric acid produced commercially by neutralising phosphoric acid with sodium hydroxide in a 1:1 molar ratio. It is widely used in food as a chemical leavening/raising agent, acidity regulator, and sequestrant, primarily in baked goods, processed meats, and seafood products.

Safety summary

The regulatory and scientific consensus.

EFSA (2019) derived a group ADI of 40 mg/kg bw/day (expressed as phosphorus) covering all food phosphates (E338–452), while JECFA previously set an MTDI of 70 mg/kg bw/day (as phosphorus); phosphates are considered of low acute oral toxicity with no genotoxicity or carcinogenicity concerns. High dietary phosphate additive intake is a significant concern for individuals with chronic kidney disease due to impaired phosphate excretion, and estimated daily intake from additives has more than doubled since the 1990s to approximately 1,000 mg/day. A 2024 French prospective cohort study (NutriNet-Santé) reported an observational association between higher diphosphate (E450) intake and increased premenopausal breast cancer risk, though causality has not been established.

Regulatory landscape

What food-safety regulators have decided.

Jurisdiction	Status	Note
EFSA (European Food Safety Authority) (European Union)	Approved	Group ADI of 40 mg/kg bw/day expressed as phosphorus, covering all food phosphates E338–341, E343, E450–452. Permitted as raising agent, acidity regulator, and sequestrant under Regulation (EC) No 1333/2008. E450i is water-soluble and not subject to nano-particle concerns unlike some other phosphate sub-types.source
FSSAI (Food Safety and Standards Authority of India) (India)	Approved	Permitted food additive under FSSAI Food Safety and Standards (Food Products Standards and Food Additives) Regulations; conditions of use generally aligned with Codex Alimentarius/JECFA guidance.source
FDA (Food and Drug Administration) (United States)	Approved	Listed as GRAS under 21 CFR 182.6769 (sodium acid pyrophosphate) as a multipurpose food additive; permitted uses include leavening agent, sequestrant, emulsifier, and stabiliser. No numerical ADI established by FDA.source

Who should approach with care

Whose guidance would steer them away.

Kidney Disease — Impaired phosphate excretion in chronic kidney disease leads to hyperphosphataemia; high dietary phosphate additives, which are more bioavailable than naturally occurring phosphate, significantly worsen this condition and increase cardiovascular mortality risk.

Heart Disease — Elevated serum phosphate from additive-rich diets is associated with increased cardiovascular risk; patients with existing heart disease should limit intake of processed foods containing E450i.

Children — EFSA noted that dietary exposure to phosphate additives in children from processed food consumption may approach or exceed the group ADI, warranting caution over high and frequent consumption of products containing E450i.

Elderly — Age-related decline in renal function reduces phosphate clearance efficiency, increasing vulnerability to the adverse systemic effects of high phosphate additive intake.

Research citations

The sources behind this verdict.

1WHO. JECFA Food Additives Database: Disodium Dihydrogen Diphosphate (INS 450i). apps.who.int
2PubMed. Food additive emulsifiers and cancer risk: Results from the French prospective NutriNet-Santé cohort, 2024. pmc.ncbi.nlm.nih.gov
3EFSA. Re-evaluation of phosphoric acid–phosphates – di-, tri- and polyphosphates (E 338–341, E 343, E 450–452) as food additives and the safety of proposed extension of use, 2019. efsa.europa.eu
4PubMed. Re-evaluation of phosphoric acid–phosphates – di-, tri- and polyphosphates (E 338–341, E 343, E 450–452) as food additives and the safety of proposed extension of use (PMC full text), 2019. pmc.ncbi.nlm.nih.gov
5PubMed. Phosphate Additives in Food—a Health Risk, 2012. pmc.ncbi.nlm.nih.gov

Independently researched5 citations