Total dietary phosphate and the group ADI
The European Food Safety Authority completed a full re-evaluation of food-additive phosphates in 2019. It set a group acceptable daily intake of 40 mg phosphorus per kilogram of body weight per day across all phosphate additives combined (E338 to E452 group). Modelling of dietary exposure found that high consumers, particularly children eating a lot of processed foods, can approach or exceed this level from additive sources alone, not counting the phosphate already present naturally in meat, dairy and cereals.
EFSA set a group ADI of 40 mg phosphorus per kg body weight per day for all food-additive phosphates and found that high-end consumers, especially children, may exceed it when additive-source phosphate alone is modelled.
2019Regulatory reviewEFSA Panel on Food Additives and Flavourings (FAF), EFSA Journal 2019;17(6):5674
Cardiovascular risk and high dietary phosphate
Observational studies in general populations have found that people with higher total dietary phosphate intake have elevated rates of cardiovascular events and all-cause mortality. The proposed mechanism is that excess phosphate raises circulating fibroblast growth factor 23 (FGF23) and parathyroid hormone, which in turn promote arterial calcification and left ventricular hypertrophy. These findings are from observational data and confounding by overall diet quality cannot be ruled out, but the signal is consistent across several large cohorts.
Higher serum phosphate and dietary phosphate load were associated with increased cardiovascular mortality in observational cohort data, with proposed mechanisms including raised FGF23 and vascular calcification.
2007ObservationalDhingra et al., Archives of Internal Medicine
A systematic review found consistent associations between higher dietary phosphate intake and cardiovascular and all-cause mortality across multiple prospective cohorts.
2013ObservationalCalvo & Uribarri, Advances in Nutrition
Kidney disease: added phosphate is absorbed differently
Phosphate from food additives (inorganic salts) is absorbed in the gut more readily than phosphate bound in proteins in natural foods. For people with chronic kidney disease, who already struggle to excrete phosphate, additive-sourced phosphate represents a more concentrated and quickly absorbed load. Regulatory guidance singles out this group as those most at risk from high additive phosphate intake.
Inorganic phosphate additives are absorbed at approximately 80-100% efficiency in the gut, compared to roughly 40-60% for organic phosphate in protein-bound foods, making additive sources disproportionately burdensome for people with impaired kidney phosphate excretion.
2010ObservationalKalantar-Zadeh et al., Journal of the American Medical Association
EFSA's 2019 opinion specifically identified people with chronic kidney disease as a subgroup for whom additive phosphate intake warrants particular attention.
2019Regulatory reviewEFSA Panel on Food Additives and Flavourings (FAF), EFSA Journal 2019;17(6):5674