Lactic acid
Lactic acid gives foods a tart taste and helps control acidity. It can also help preserve foods. Often made by fermenting sugars, it is called E270 on some labels. The added acid is different from starter cultures used to ferment foods.
Also known as
lactic acid · L-lactic acid · D-lactic acid · DL-lactic acid · 2-hydroxypropanoic acid · 2-hydroxypropionic acid · E270 · E 270 · INS 270
Why PRūF tracks it
D-lactate can accumulate and upset the body’s acid balance in susceptible people, including those with short bowel syndrome or rare metabolic disorders, while ordinary food use has not shown the same risk in healthy consumers.
Read the research
Lactic acid is an organic acid used for flavour, acidity control and preservation. Food-grade products may contain the L form, the D form or a mixture; an ingredient list usually does not identify the form or amount. These forms share a name but are processed differently by the body. The L form is a normal part of human energy metabolism.
D-lactate accumulation can cause an acid imbalance in susceptible people, particularly those with short bowel syndrome or rare inherited problems breaking it down. Very young infants also need separate consideration. US rules permit specified food uses under good manufacturing practice but exclude infant foods and formulas from this permission. WHO experts assigned an acceptable daily intake without a numerical limit, while advising against D and mixed forms in infant foods.
This does not mean unlimited quantities are appropriate. Recent clinical studies concern vulnerable patients and do not show that ordinary added lactic acid causes illness in healthy consumers. Menu disclosures establish neither a dose nor an individual health risk.
Research reviewed on October 22, 2026 · 10 sources
Checking your order
A food that isn’t listed here may still contain this ingredient. Check with the restaurant if you need to avoid it.
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The published research used in the PRūF app.
- 21 CFR 184.1061 Lactic acid
FDA/eCFR · Current through 2026-10-20 · Accessed 2026-10-22
- Lactic acid and its ammonium, calcium, potassium and sodium salts, FAS 5
WHO/JECFA · 1974 · Accessed 2026-10-22
- Lactic acid evaluation database entry
WHO/JECFA · 1973 ADI; later flavouring evaluation · Accessed 2026-10-22
- Safety and efficacy of lactic acid on kangaroo, wild pig, goat and sheep carcases
EFSA CEP Panel · 2022-05-12 · Accessed 2026-10-22
- Identification of human D lactate dehydrogenase deficiency
Monroe et al. · 2019-04-01 · Accessed 2026-10-22
- Human D-Lactate Dehydrogenase Deficiency: A Case Report in a Young Boy
Sloth et al. · 2025-07-17 · Accessed 2026-10-22
- Serum and urinary D-lactate in pediatric intestinal failure: clinical associations and reference values
Halasova et al. · 2026-08-29 · Accessed 2026-10-22
- List 10: Permitted Acidity Regulators and Acid-Reacting Materials
Health Canada · 2025-10-20 · Accessed 2026-10-22
- Approved additives and E numbers
UK Government/FSA · 2026-06-25 · Accessed 2026-10-22
- P1066 Supporting document 3: safety and food technology assessment
FSANZ · 2026-05-26 · Accessed 2026-10-22
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