Combining Retinol and AHA in Formulations

It is generally advised against using Retinol and AHAs (Alpha Hydroxy Acids) together in the same cosmetic formulation.

Reasons for Avoiding Combination

• pH Sensitivity: Retinoids, such as Retinol and Retinal (Retinaldehyde), are most stable and effective at a specific pH range, typically slightly acidic to neutral (around pH 5.5 to 6.5). AHAs, like Glycolic Acid or Lactic Acid, require a much lower, more acidic pH (often below 4) to effectively exfoliate the skin. Formulating them together at a low pH can cause the retinoid to degrade and lose its efficacy.
• Increased Skin Irritation: Both retinoids and AHAs are potent active ingredients that can cause skin irritation, redness, peeling, and sensitivity, especially when first introduced or used at higher concentrations. Combining them in one product significantly increases the likelihood and severity of these side effects, potentially damaging the skin barrier.

Alternative Approaches

Instead of combining them in a single product, consider these methods:

• Alternate Usage: Use a retinoid product on one night and an AHA product on a different night. This allows you to benefit from both ingredients without the increased risk of irritation and potential degradation.
• Use Different Forms: Some newer forms of retinoids, such as encapsulated versions like HyaRetin™ (Sodium Retinoyl Hyaluronate) or Retinal-EZ™ (Encapsulated Water Dispersible Retinal), or derivatives like Retinyl Retinoate and VAE10 (Tocopheryl Retinoate), may offer improved stability or reduced irritation compared to traditional Retinol or Retinal. However, caution is still advised when combining them with AHAs.
• Consider Bakuchiol: Bakuchiol is a plant-derived ingredient often referred to as a natural alternative to Retinol. It offers similar anti-aging benefits but is generally much gentler and does not have the same pH sensitivity issues as traditional retinoids. It can be a good option for those with sensitive skin or for use in formulations where pH is a concern.

While ingredients like Vitamin A Palmitate are also Vitamin A derivatives, they are less potent than Retinol or Retinal and may still pose compatibility challenges with low pH AHA formulations.

In summary, to maximize the effectiveness of both Retinol/retinoids and AHAs and minimize skin irritation, it is best to use them separately or on alternate days, rather than combining them in the same formulation.