Citric Acid

AHA (Alpha Hydroxy Acid)
Benefits
Hair GrowthLiftingCleansingSoothingExfoliatingLighteningAntioxidant

What is Citric Acid?

Citric acid is a weak organic acid, chemically known as 2-hydroxypropane-1,2,3-tricarboxylic acid, abundant in citrus fruits such as lemons, limes, and oranges. Derived through fermentation or extraction, it belongs to the alpha hydroxy acid (AHA) family used widely in skincare products like cleansers, toners, serums, and peels. Functionally, it acts as a keratolytic agent by breaking bonds between dead skin cells, promoting their removal for smoother texture. It also serves as a pH adjuster to optimize formula stability and efficacy, a chelating agent binding metal ions to prevent discoloration or degradation, and a mild buffering component maintaining consistent acidity. In higher concentrations, it contributes to brighter appearance by accelerating cell turnover, while low levels enhance preservative performance without direct skin impact.

Comedogenic Rating 0/5 Low risk of clogging pores
EWG Safety Rating 1-2 View on EWG →
PubChem View on PubChem →

Roles in Formulation

This ingredient serves the following purposes in cosmetic formulations:

Chelating agent
Binds to metal ions to prevent them from affecting product stability or skin.
Fragrance ingredient
Contributes scent character and/or masks base odors, shaping the overall sensory experience of the formula (subject to allergen and IFRA considerations).
PH adjuster
Raises or lowers pH to the target range, supporting ingredient performance, preservative efficacy, stability, and user comfort.
Buffering agent
Maintains the pH stability of a formulation.
Masking
Reduces perception of unpleasant odors or tastes by neutralizing them or covering them with more acceptable sensory notes.

Benefits

Supports exfoliation to smooth skin texture.

Aids in lightening by promoting even tone.

Acts as antioxidant to protect against oxidative stress.

Who It's For

A quick guide for who this ingredient may suit (and who should be cautious).

Who May Benefit Who Should Avoid
People with dull or uneven skin seeking gentle renewal.
Users with sensitive skin prone to irritation.
Those using products for cleansing and pH balance.
Those experiencing barrier compromise or eczema.
Individuals interested in formula-stabilizing ingredients.
People using high-concentration acid products frequently.

Safety Notes

  • Generally recognized as safe in cosmetics at typical levels.
  • May cause mild stinging if pH is very low; dilute properly.

Frequently Asked Questions about Citric Acid

What is citric acid's main role in skincare?

It primarily adjusts pH, chelates metals, and provides mild exfoliation.

Is citric acid comedogenic?

No, it has a comedogenic rating of 0, suitable for acne-prone skin.

Can citric acid suit sensitive skin?

Use caution; it may irritate if skin is very reactive or barrier-weakened.