As dermatologists, patients often seek our advice for recommendations of cosmetic and beauty care products, particularly those available over-the-counter. The growth in this segment has been tremendous despite the pandemic. According to Global Market Insights, Inc., the retinol market was estimated at $24.37 million in 2020 and is expected to have a compounded annual growth rate above 6.5% going forward. Occupying the same market growth were ingredients like niacinamide and antioxidants. So, what is it about retinol (an ingredient that is not necessarily “new”) that continues to make it a staple in skincare routines? In many ways, it comes down to efficacy, which is a parameter that has changed in the over-the-counter marketplace in the last few years. Previously, it was thought the only effective form of this Vitamin A derivative was retinoic acid, which is available by prescription. Interestingly, innovation and changes to production, formulation, and carrier design have created retinol formulations consumers can directly purchase that lead to good results for a variety of skin concerns.
All-trans retinol was synthesized in a laboratory in the 1940s and the effects of it on the skin began to be established in the 1960s. However, it was only in the 1990s that the molecule was stabilized enough to be used for consumer and patient use. Since that time, formulation innovations have created retinols that are more stable to pH, light, and oxygen. Now, these formulas contain enough active ingredient to be used to treat an array of problems from acne and acne scarring to fine lines, discoloration, and even solar damage. Interestingly, the history of retinol parallels that of Vitamin A, and since its exploration for use on skin, the biggest challenge has been instability which needs to be controlled not only in the formulation itself but along the entirety of the production process from synthesis to bottling and storage. While retinoic acid is effective, one of the main barriers to widespread use has been irritation which leads to a decrease in compliance. It is formulation innovation by industry that actually reduced this irritation potential thus making it more palatable for patients to use retinols on a regular basis for anti-aging benefits.
Traditionally, there has been an inability to understand the difference between over-the-counter options and an inherent distrust by physicians of what percent of retinol any product contained. With advances, it is now clear that the concentration of retinol is only part of the story. There are several components in any given retinol product that can influence how it reacts on the skin. Vehicles can be cream, or lotion based and even exhibit a polarity that will determine how much of the retinol penetrates the stratum corneum. Concentration can be modulated by carrier molecules that allow the retinol to achieve controlled skin absorption, and production conditions and shelf life can alter the stability of the molecule itself. As a result, simply looking at the form of retinol in the package or its concentration is not enough to determine efficacy of a retinol product. Similarly, increased cost does not equate to better design of the product itself.
In this review, we aim to educate physicians on vitamin A metabolites; namely retinyl ester, retinol, retinaldehyde, and retinoic acid. We know that when choosing a natural vitamin A metabolite there is often a tradeoff between stability and efficacy however in reviewing the many facets of production and formulation, one can begin to see how current day retinol innovation allows for increased stability. The stability improvement allows for improved preclinical and clinical efficacy. By the end, we hope that dermatologists will understand that a retinol can in fact be an ideal retinoid for cosmetic solutions.
All-trans retinol was synthesized in a laboratory in the 1940s and the effects of it on the skin began to be established in the 1960s. However, it was only in the 1990s that the molecule was stabilized enough to be used for consumer and patient use. Since that time, formulation innovations have created retinols that are more stable to pH, light, and oxygen. Now, these formulas contain enough active ingredient to be used to treat an array of problems from acne and acne scarring to fine lines, discoloration, and even solar damage. Interestingly, the history of retinol parallels that of Vitamin A, and since its exploration for use on skin, the biggest challenge has been instability which needs to be controlled not only in the formulation itself but along the entirety of the production process from synthesis to bottling and storage. While retinoic acid is effective, one of the main barriers to widespread use has been irritation which leads to a decrease in compliance. It is formulation innovation by industry that actually reduced this irritation potential thus making it more palatable for patients to use retinols on a regular basis for anti-aging benefits.
Traditionally, there has been an inability to understand the difference between over-the-counter options and an inherent distrust by physicians of what percent of retinol any product contained. With advances, it is now clear that the concentration of retinol is only part of the story. There are several components in any given retinol product that can influence how it reacts on the skin. Vehicles can be cream, or lotion based and even exhibit a polarity that will determine how much of the retinol penetrates the stratum corneum. Concentration can be modulated by carrier molecules that allow the retinol to achieve controlled skin absorption, and production conditions and shelf life can alter the stability of the molecule itself. As a result, simply looking at the form of retinol in the package or its concentration is not enough to determine efficacy of a retinol product. Similarly, increased cost does not equate to better design of the product itself.
In this review, we aim to educate physicians on vitamin A metabolites; namely retinyl ester, retinol, retinaldehyde, and retinoic acid. We know that when choosing a natural vitamin A metabolite there is often a tradeoff between stability and efficacy however in reviewing the many facets of production and formulation, one can begin to see how current day retinol innovation allows for increased stability. The stability improvement allows for improved preclinical and clinical efficacy. By the end, we hope that dermatologists will understand that a retinol can in fact be an ideal retinoid for cosmetic solutions.
