Ascorbic Acid | whatsinit

About

What it is and where it shows up.

Ascorbic acid (Vitamin C) is an essential water-soluble vitamin and potent antioxidant naturally present in fruits and vegetables, added to food to prevent oxidative degradation, maintain colour, and supplement nutritional content. It also enhances iron absorption and supports collagen synthesis.

Safety summary

The regulatory and scientific consensus.

Ascorbic acid is considered safe at food-use levels, with EFSA and FDA confirming no significant risk under normal conditions; adverse effects have only been reported at very high doses of several grams per day (e.g., >5 g/adult/day). No formal numerical ADI has been established by JECFA or EFSA for food additive use, as the available data did not allow setting a formal upper limit at any age. Individuals with kidney disease or G6PD deficiency should exercise caution with high supplemental doses.

Regulatory landscape

What food-safety regulators have decided.

Jurisdiction	Status	Note
FSANZ (Food Standards Australia New Zealand) (Australia)	Approved	Ascorbic acid and all additives based on it (E300–E304) are approved in Australia and New Zealand per FSANZ Food Standards Code.source
EFSA (European Food Safety Authority) (European Union)	Approved	Approved as E300 under Regulation (EC) No 1333/2008 at quantum satis (no specific maximum) for most food categories. EFSA 2015 re-evaluation confirmed safety. EU Tolerable Upper Intake Level (UL) for adults from all sources is 1000 mg/day (set by SCF/EFSA NDA Panel, 2004). E301 (sodium ascorbate) and E302 (calcium ascorbate) are also approved.source
Food Standards Agency (FSA) / Food Standards Scotland (FSS) (United Kingdom)	Approved	Approved E-number E300 retained post-Brexit; use at quantum satis in most food categories consistent with pre-Brexit EU rules.source
FSSAI (Food Safety and Standards Authority of India) (India)	Approved	Permitted as food additive (INS 300) in the FSS (Food Products Standards and Food Additives) Regulations, 2011. Esters and salts of Vitamin C listed at GMP level; total level must not exceed the RDA specified by ICMR where no specific maximum is set by the Food Authority.source

Who should approach with care

Whose guidance would steer them away.

Kidney Disease — High supplemental doses of ascorbic acid (>1 g/day) can increase urinary oxalate excretion, raising the risk of calcium oxalate kidney stones in individuals with pre-existing renal impairment or a history of nephrolithiasis.

G6pd Deficiency — High-dose ascorbic acid can trigger oxidative haemolysis in individuals with Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency; food-level amounts are generally tolerated but supplemental doses should be discussed with a physician.

Diabetes — Very high supplemental doses of vitamin C may interfere with the accuracy of capillary blood glucose monitoring devices, potentially yielding falsely elevated or depressed readings.

Gout — Although moderate dietary vitamin C may lower uric acid levels, very high supplemental doses can paradoxically promote uric acid retention in some individuals, warranting monitoring in those with gout.

Research citations

The sources behind this verdict.

1FDA. Food Additive Status List – Ascorbic Acid (21 CFR 182.3013, 182.5013, 182.8013). fda.gov
2FDA. Food Additive Status List – Ascorbic Acid. fda.gov
3FDA. GRAS Notice GRN-690 – Fruit and Vegetable Vitamin Extract (Ascorbic Acid safety data). fda.gov
4other. Commission Regulation (EU) 2020/1419 – Use of ascorbic acid (E 300) and citric acid (E 330) on white vegetables, 2020. eur-lex.europa.eu
5PubMed. Opinion on the re-evaluation of ascorbyl palmitate (E 304i) as a food additive in foods for infants below 16 weeks of age, 2020. pmc.ncbi.nlm.nih.gov
6other. The Use of Ascorbic Acid as a Food Additive: Technical-Legal Issues, 2016. pmc.ncbi.nlm.nih.gov

Independently researched8 citations