Glycolic vs Lactic Acid: Body Exfoliation Explained

Chemical exfoliation on the body is often approached with more force than necessary. The skin on your limbs is thicker than that of the face, yet it remains susceptible to irritation if treated with the wrong molecular weight of alpha hydroxy acid. Glycolic and lactic acids represent the two most common choices for non-professional body maintenance.

Understanding the difference between these two hinges on how they interact with the skin barrier. While both function by dissolving the intercellular glue holding dead cells together, their physical size determines how quickly and deeply they settle into the surface, dictating the intensity of the result.

1. Begin with a clean, dry surface. Never apply an acid treatment to damp skin. Water can accelerate the penetration of the active ingredient, leading to unnecessary stinging. Use a gentle, pH-balanced cleanser and ensure you have towel-dried the skin thoroughly before starting.
2. Choose your acid based on skin density. Select lactic acid if you have thinner skin on your chest or neck, as its larger molecular size keeps it closer to the surface. Use glycolic acid for areas with thicker skin, such as the knees, elbows, or heels, where deeper penetration is required to smooth texture.
3. Distribute the product evenly. Pour a small amount into your palm or onto a reusable cotton pad. Apply in long, sweeping motions, moving toward the heart. Avoid broken skin or areas with active irritation, as acids will intensify these conditions.
4. Allow the formulation to set. Let the product air-dry completely before putting on clothing. Wearing tight fabrics immediately after application can rub the product off or create a friction point that induces sensitivity. Patience here prevents uneven absorption.
5. Lock in hydration. Follow with a simple, fragrance-free moisturizer to support the barrier you have just exfoliated. This step is mandatory, as it prevents trans-epidermal water loss. The acid does the work of clearing cells, while the cream performs the work of maintenance.

Glycolic acid penetrates quickly; lactic acid provides hydration while it exfoliates.