What it is
Citric acid is a type of alpha hydroxy acid (AHA) derived from citrus fruits such as lemons, limes and oranges. In skincare and body care, citric acid is valued both as an active ingredient and as a supportive one. As an active, citric acid offers gentle exfoliation, helping to smooth and brighten the skin. As a support, it’s often used to adjust the pH of formulations, keeping products stable and effective.
Compared with stronger AHAs such as glycolic acid, citric acid is milder, making it useful across a wide range of everyday products. Citric acid is commonly included in cleansers, serums, creams and exfoliating treatments, and also plays a role in body scrubs and bath products.
How it works in skincare
Citric acid works by loosening the bonds between dead skin cells at the surface, encouraging them to shed more easily. This mild exfoliation reveals fresher, smoother skin and helps reduce the appearance of dullness. Regular use can support a more even skin tone and improve the absorption of other active ingredients.
Beyond exfoliation, citric acid has antioxidant properties. It helps neutralise free radicals, unstable molecules generated by sun exposure and pollution that contribute to skin ageing. In this way, citric acid supports both immediate brightness and longer-term skin health.
In formulations, citric acid plays an equally important role in balancing pH. The skin’s natural barrier, known as the acid mantle, functions best in a slightly acidic environment. Citric acid helps bring products into that optimal range, ensuring they work effectively while respecting skin balance.
In hand and body care, citric acid adds refinement by smoothing rough patches and giving skin a fresher look and feel. It’s also often used in bath soaks for its fizzing effect when combined with carbonates, adding a sensorial boost.
At higher concentrations, citric acid is sometimes used in professional chemical peels, but in everyday products the ingredient is typically gentle and well-tolerated. Those with sensitive skin should still patch test, as overuse can sometimes cause dryness or irritation.