What’s a Retinoid? The Role of Vitamin A Derivatives in Skin Care

Retinol
Retinol (Vitamin A)

The contemporary skin care market boasts thousands of products, each containing hundreds of active ingredients, offering a vast array of benefits.

Acne control, radiant skin, and less visible signs of aging are among some of the more popular claims made by modern products, and creams and serums containing retinoids are certainly no stranger to the spotlight.

Very few compounds have the ablility to reliably deliver the benefits of retinoids, yet even making a decision on what type of retinoid to use can be a daunting task in itself.

Retinoids are a class of chemical compounds that are derived from vitamin A; there are seemenly endless types and formulations designed for various purposes.

Retinoids bind to receptors within the cell that affect DNA regulation, and they are intimately involved in the mediation of cell proliferation and differentiation.

Retinoids are common active ingredients in both over-the-counter (OTC) and prescription creams that bind to nucleic acid (DNA) receptors in the skin cells to:

  • Stimulate cellular turnover in the epidermis.
  • Thin the top layer of skin.
  • Promote collagen production/repair.
  • Prevent collagen damage/breakdown.
  • Decrease sebum (oil) production.
  • Help to clear debris and dead skin cells from pores.
  • Play a role in the prevention of skin cancers.

SkinCeuticals ACD

Classes of Retinoids

Some types of retinoids (i.e., retinol derivatives) must be converted (oxidized) to retinoic acid (the biologically active form) after they are applied to the skin in order to be effective.

Recalling one of my favorite college classes, organic chemistry (I know–I know…but it really was interesting…LOL), alcohols (e.g. retinol) are oxidized to form aldehydes (e.g. retinaldehyde), which are subsequently oxidized to form a carboxylic acid (retinoic acid).

Retinol
Retinol (Vitamin A)
Retinal
Retinaldehyde
Tretinoin
Tretinoin (Retinoic Acid)

 

 

 

 

 

Free radicals damage cellular tissue by “stealing” electrons from the tissues in order form stable compounds.  Retinoids are effective antioxidants, which donate electrons (become reduced) to free radicals, which accept the electrons (become oxidized) and form nonreactive compounds that compounds that do not damage cellular tissue.

Free-Radicals-and-Antioxidants
The antioxidant (electron donor) reacts with the free radical (electron acceptor).

Retinol derivatives are commonly found in OTC creams, while retinoic acid derivatives (with the exception of adapalane) require a prescription.

Retinoic acid derivatives in prescription retinoids can be up to 20 times as potent as their retinol-based counterparts. They are sometimes classified according to how long it’s been since they’ve been around:

  • 1st. Generation (older retinoids)
    • Tretinoin (trans retinoic acid)
    • Alitretinoin
    • Retinol
    • Retinal
  • 2nd. Generation
    • Etretinate
    • Acitretin
  • 3rd. Generation (newer retinoids)
    • Adapalene
    • Tazarotene

Retinoids in Your Routine

Upon your initial decision to incorporate a retinoid cream into your own skincare routine, it’s logical to start with an OTC retinol derivative, since these formulations are historically milder and cause less irritation than prescription versions.

A common side effect of topical retinoid products is their tendency to irritate the skin, which frequently results in slight burning, peeling, or mild redness.  For this reason, it is always prudent to test retinoid creams in an inconspicuous area of skin prior to their first use.

Retinoids uncover new skin cells as they stimulate cellular regeneration, and these new cells are more vulnerable to sun damage.  Care should be taken to apply retinoid products at night to avoid concurrent sun exposure; alternatively, a sunscreen with a minimum SPF value of 30 can be applied afterward.

It’s wise to select creams that contain moisturizing ingredients (e.g., hyaluronic acid, ceramides, shea butter) in order to minimize irritation and dryness.

The ideal time to apply retinoid creams is about 20-30 minutes after washing your face, so that your skin is completely dry, since application of a retinoid cream to wet skin is more likely to cause irritation.

A pea-sized (1/4″ diameter) amount should be evenly smoothed over facial skin; more product does not confer better cosmetic results, and it may take 6-12 months of routine retinoid use for discernable results to mainfest.

Given that benzoyl peroxide and salicylic acid may deactivate retinoids, their simultaneous use is best avoided.

Retinol Derivatives

Since retinol derivatives in OTC creams tend to be less potent, it’s generally best to start with one of these and work toward a prescription retinoid cream if necessary.

Retinol derivatives are labeled as being a cosmetic, giving them less stringent marketing regulations than those of retinoic acid derivatives.

OTC preparations often contain one of the following types of retinoids:

  • Retinyl palmitate is the least potent type of retinoid; it is ideal for sensitive or very dry skin with minimal signs of aging. Its role in face creams is mainly as a stabilizer.
  • Retinaldehyde is common in OTC preparations and is slightly more potent than retinyl palmitate; it is an intermediate compound in the production of retinoic acid from retinol.
  • Retinol is a specific type of vitamin A; it is the most potent OTC retinoid.
    • SkinCeuticals Retinol 1.0 Refining Night Cream
      • Contains ceramides, AHAs, shea butter, and dimethicone to reduce irritation.
      • Non-comedogenic.
      • Fragrance-free.
    • Neutrogena Anti-Wrinkle Deep Wrinkle Night Mositurizer
      • Contains Retinol SA (sustained action retinol formulation).
      • Hyaluronic acid.
      • Fragrance-free.
    • NeoCutis Nouvelle + Intensive Anti-Aging Cream
      • Contains 0.06% retinol in a microbead formulation (sustained release).
      • Melaplex skin-brightening (hydroquinone-free) complex.
    • Roc Retinol Correxion Deep Wrinkle Night Cream
      • Contains retinol and hyaluronic acid.
      • Non-comedogenic.
      • Oil-free.
    • SkinMedica Retinol Complex 1.0
      • Contains retinol, ceramides, niacinamide, peptides, and vitamin E.
    • Olay Regenerist Retinol 24 Night Moisturizer
      • Contains niacinamide.
      • Fragrance-free.
    • Avene RetrinAL 0.1 Intensive Cream
      • Contains retinaldehyde.
      • Contains pro-elastin peptide and pre-tocopheryl (stable form of vitamin E).

Retinoic Acid Derivatives

The more potent topical retinoids require a prescription and are subject to tighter regulation and more intense scrutiny than retinol-based cosmetics.

The retinoic acid derivatives either contain retinoic acid itself or a derivative of it:

  • Tretinoin (Retin-A, Retin-A Micro, Renova, Refissa) is also known as trans retinoic acid; it has been around long enough for sound, evidence-based data to accumulate supporting its effects on collagen production and repair.
    • Retin-A Micro is used to treat acne; its efficacy in the treatment of other skin conditions is not currently known.
    • Renova (0.02% tretinoin) is an emollient cream (contains fragrance) used in the treatment of aging skin.
    • Refissa (0.05% tretinoin) is a fragrance-free emollient cream used to treat fine lines and wrinkles; it has more of an ointment-like consistency than Renova.

      Tretinoin-Cream
      Tretinoin Cream (Generic Refissa)
  • Tazarotene is another potent retinoic acid derivative that is very similar to tretinoin; however, it is more irritating to the skin. It is used in the treatment of both acne and plaque psoriasis.
    • Avage 0.1% is a cream formulation.
    • Tazorac 0.1% is a gel formulation.
  • Adapalene (Differin) was formerly only available by prescription; is now available OTC in the 0.1% concentration. It is the least irritating of the retinoic acid derivatives and preferentially affects the more oily areas of the skin. It works on different receptors than tretinoin, and its efficacy in the treatment of fine lines and wrinkles is presently unclear.
    • Differin Gel 0.1% Adapalene should be used with a moisturizer.

Retinoid Cream Appeal

Retinoids are vitamin A derivatives that are versatile components in skincare products possessing multiple benefits, including a reduction in the appearance of visible signs of aging with routine use.

Two main classes of retinoid creams are retinol derivatives and retinoic acid derivatives; the former are OTC creams, and the latter are almost universally prescription products.

The best time to apply retinoid creams is at night, between the application of face serum and the application of moisturizer; if retinoids are used during the day, a sunscreen should be applied afterward with an SPF value of at least 30 to minimize potential irritation with sun exposure.

Since creams containing retinol derivatives are generally milder than those containg retinoic acid derivatives, they are a logical starting point when adding an retinoid product to your skincare routine.

Retinoid creams can first be applied every other night, gradually progressing to nightly use after 2-3 weeks in the absence of irritation (e.g., redness, dryness, or peeling).

Possessing a multitude of benefits without significant risks, retinoid products have become a mainstay of skin care routines the world over.

Let me know which retinoid product(s) that you like or dislike and reason(s) why in the “Comments” section below.

Leave a Reply

Your email address will not be published. Required fields are marked *