Question of the month May 2011: Retinol

Beste Paula,

According to research, what is the minimum amount of retinol required for efficacy? Are higher amounts going to provide better or faster results?
 

Alice, via email

Dear Alice,

 Generally, 0.15% retinol is considered the minimum effective amount though amounts around 0.25% are more common. Potency-wise this amount is believed to be comparable to prescription retinoid products with 0.01% tretinoin but with fewer side effects. Some retinol products contain more than 0.25%, but usually not a lot more. Larger amounts of retinol are not inherently better than what’s standard. Amounts of 0.5% and above may cause a strong irritant kick-back, evidenced by persistent flaking, dryness, and a sunburn-like feeling that leaves skin tender to the touch. These symptoms often appear within the first few weeks of daily use. Of course, some women have hardier skin and can tolerate these amounts, especially if they space application out between days. We are working on a specialized retinol serum for our RESIST line. Final details have not been set as of yet, but the amount of retinol will be slightly greater than what’s available in our current Super Antioxidant Concentrate serums with retinol. My team and I are being very careful to ensure this antiaging superstar ingredient remains active while minimizing the potential for side effects with specialized ingredients. And of course, since retinol is an incredibly fragile ingredient, we are taking steps to ensure it is packaged to ensure stability, too. Never buy a retinol product that’s packaged in a jar or clear container. These types of packaging will quickly degrade the retinol, leaving you with an ineffective product.