A gently exfoliating AHA that helps to remove the top layer of dead skin cells. In comparison to other AHAs, citric acid has been shown to be one of the least effective. It is also very commonly used as a stabilizing and pH-controlling agent.
Citric acid is an organic compound with the chemical formula C6H8O7, primarily found in citrus fruits such as lemons, oranges, and grapefruits. This acid is known for its tangy taste and is commonly used as a preservative and flavor enhancer in the food and beverage industry. In the skincare world, citric acid is primarily recognized for its role as an Alpha-Hydroxy Acid (AHA) and a pH adjuster.
As an Alpha-Hydroxy Acid (AHA), citric acid is extensively used in skincare products. AHAs, derived from plant and animal sources, are primarily used for exfoliation. They peel away the surface of the skin, allowing for the generation and replacement with new, more evenly pigmented skin cells.
Citric acid also serves as a pH adjuster in skincare products, maintaining an optimal pH level for product effectiveness. Additionally, citric acid acts as a chelator, meaning it can bind to and neutralize metal ions to prevent their adverse effects on the skin.
Several benefits of citric acid for the skin have been identified:
Dark Spots and Hyperpigmentation: By promoting skin cell turnover, citric acid can assist in reducing the appearance of dark spots and hyperpigmentation.
Sebum Regulation: While explicit studies investigating citric acid's effect on sebum regulation are limited, AHAs in general, including citric acid, are used in products intended for oily and acne-prone skin, indicating possible benefits in this area.
However, in comparison to other AHAs, citric acid has been shown to be one of the least effective. Glycolic and lactic acid scored higher than citric acid in all measured parameters (skin cell renewal, moisturization, anti-aging properties) and were also less irritating.
Generally, citric acid is deemed safe for cosmetic use. However, like other AHAs, it can increase sun sensitivity, making the skin more susceptible to sun damage. Therefore, applying sunscreen is crucial when using products containing citric acid or any other AHA.
For those with sensitive skin or allergies, it is recommended to perform a patch test to ensure that the product doesn't provoke any adverse reactions.