A Guide to AHA Percentages

Alpha hydroxy acids act as solvents for the intercellular glue holding dull surface cells to the skin. Selecting the correct concentration is a matter of determining your tolerance rather than seeking the highest available percentage. The difference between 5% and 12% is measured in how rapidly and deeply the liquid interacts with the upper layers of the epidermis.

Higher concentrations do not equate to better results for every person. Success with these ingredients requires a disciplined approach to frequency and a consistent baseline of hydration.

1. Prepare the surface. Begin with a clean face using a neutral, non-foaming cleanser. Ensure the skin is completely dry before application to prevent uneven distribution. Water acts as a catalyst that can accelerate penetration beyond what is intended.
2. Measure the dose. Dispense a small amount—roughly the size of a pea—onto a clean palm or a reusable cotton round. Apply the liquid in an even, thin layer over the face, avoiding the immediate eye area and corners of the lips. Maintain a steady, downward motion to ensure full coverage without saturation.
3. Allow for absorption. Let the product sit on the skin undisturbed for several minutes. Do not rinse the product off unless the specific directions for your chosen formula indicate it is a wash-off treatment. This period is essential for the acid to settle into the stratum corneum.
4. Seal and protect. Follow the exfoliant with a basic, fragrance-free moisturizer. A barrier-focused cream helps mitigate the immediate sensation of tightness that often follows chemical exfoliation. Keeping the skin hydrated preserves the integrity of the surface layer.

Exfoliation is not an endurance sport; the goal is consistency, not intensity.