This is Part 2 of my discussion about Vitamin A. There is just so much to say about Vitamin A, there was no way to confine it to just one post. While Part 1 was a general overview about why the body needs Vitamin A, which foods contain high amounts of it, and what happens if people consume too little or too much Vitamin A; this part will focus more on the different uses of Vitamin A in skincare.
There are many derivatives of Vitamin A used in every price range of skincare products ranging from drug store brands, to heavily marketed department and specialty store brands, to professional and medical strength products, all in addition to the prescription-only retinoids. Before we delve into the different types of Vitamin A, what they do, and why one may be better for certain conditions than others, we need to understand how Vitamin A is stored and how it metabolizes in the body.
Vitamin A Metabolism
Have a look at this diagram of how Vitamin A metabolizes in the body.
You can see that at the very top, we have the Vitamin A we get from our food. Vitamin A exists in our bodies in a preformed state from the retinol we get from consuming animal foods containing it. The carotenoids from plant foods we consume are converted by the body into beta carotene. Beta carotene then converts to retinal, or retinaldehyde (and don?t let the ?aldehyde? suffix scare you?this is not a toxic ingredient like formaldehyde), which is the precursor to certain Vitamin A esters like retinyl propionate; as well as Vitamin A acid, or retinoic acid.
So you can see how there are different forms of Vitamin A, and if you read labels you will note that many of these, in addition to other varieties of Vitamin A are commonly used in skin care products ranging from acne treatments, to anti-aging products, even to sun protection products. How do you know which one is the best to use? Don?t they all benefit the skin? Do some benefit some skin types more than others? Let?s break it down. We?ll start at the top with prescription retinoids.
Retinoic acid, also known as Vitamin A acid is prescribed by doctors as topical (Retin-A, Differin) or in some cases oral medications (Accutane). It is prescribed as an acne medication, and is also prescribed to combat signs of aging such as fine lines and hyperpigmentation.
Retin-A, and other retinoids in its class will usually successfully improve the appearance of the skin in the short term, but is often very irritant to the skin, causing inflammation and peeling. It is for this reason that many patients stop using it. When I was a teenager and young adult suffering with acne, I was prescribed Retin-A on one occasion and Differin (considered to be less irritant) on another. Both products left my skin with a chapped and chafed look?red, tight, and peeling. It actually hurt me to smile, even with the use of the moisturizer my dermatologist had recommended at the time. I was told the irritation and inflammation would subside after a few weeks, so I hung in there and actually used the products for several months with no improvement in my symptoms. Furthermore, neither product did anything to improve my acne. So I stopped using them.
Why does this happen? While retinoic acid can be synthesized in the skin during the metabolic process of Vitamin A, it cannot be stored in the skin. Therefore any retinoic acid that is not absorbed and utilized by the skin becomes trapped in the epidermis and begins to oxidize and release free radicals, therefore compromising the skin?s barrier and creating inflammation. It also increases photosensitivity (susceptibility to UV damage). All of this actually permanently thins the dermis and speeds up the aging process in the long run.
Retinoic acid can also react adversely with other common skincare ingredients. Salicylic acid, for instance, another common acne-fighting ingredient, can cause a serious reaction with retinoic acid which could result in severe scaling, swelling, and even burns.
If you are using any form of retinoic acid and plan on getting a chemical peel, laser, or microdermabrasion treatment, or have any facial waxing done, make sure you tell your aesthetician you are using it during your consultation before you receive a treatment. Use of retinoic acid, as well as some other forms of Vitamin A is a contraindication for many of these treatments, and needs to be stopped within a certain time frame before receiving a treatment. If not, serious adverse effects on the skin can occur.
Isotretinoin, or Accutane (also known as Roaccutane), is a very strong oral retinoid that is used only in the most severe cases of acne. It is a very controversial drug, because it is linked to severe side effects and Vitamin A toxicity. It is only prescribed for a short term, and Vitamin A blood levels must be regularly monitored during the course of the medication. In my opinion, there are no mild side effects of Accutane. The side effects that are considered to be most common are all over the spectrum of maladies and include sudden onset of night blindness, hair loss or alopecia, depression, elevated triglycerides, and liver damage. The list of potential serious side effects is very long, and includes severe birth defects if taken during any part of a pregnancy (pregnancy tests are required prior to and during the use of Accutane for female patients), anaphylaxis, psychosis and suicidal tendencies, stroke, seizures, hearing impairment, and the list goes on. I know I have some very loyal readers who have taken Accutane and have dealt with it very well, but I also know of others who have not fared so well.
I do not recommend the use of Accutane for any period of time, or for any reason. I personally experienced severe pustular and cystic acne (considered to be stage?4 acne) and am living proof that it can successfully be treated without the use of this drug, or any other prescription drugs. Other forms of Vitamin A are much less irritant and still very effective.
On the opposite end of the spectrum, we have retinyl palmitate, or Vitamin A palmitate (not propionate). This is the version of Vitamin A in skincare that you typically see on drugstore cosmetics? labels. It is a much milder derivative of Vitamin A and is seen in the above diagram as kind of an end-product of the metabolic process on the ester side. It is mostly used in OTC anti-aging products and even some sunscreens which is ironic since it can cause photosensitivity like some of the other stronger retinoids. In this price range, it is not likely to be a high quality ingredient, nor is it likely to be formulated in a way that it can actually benefit the skin. Most likely, it will get trapped in the epidermis and oxidize, perpetuating free radical damage.
Retinol is seen very often in skin care products, both in higher end OTC products (department store and boutique brands) and in professional products. It is less aggressive less effective than retinoic acid, but causes a lot of skin sensitivity and irritation, and increases the skin?s vulnerability to the sun?s damaging UV rays just like retinoic acid does; therefore it cannot be used during the day. It is too strong for people with existing skin sensitivities, allergies, and rosacea. Additionally, it is highly unstable and needs to be well preserved in order to maintain any of its effectiveness once bottled. Once the bottle is opened any exposure to air, sunlight, humidity, or bacteria completely deplete it of any possible benefit.
Vitamin A Propionate
This ester of Vitamin A, also known as retinyl propionate (not palmitate) is a precursor to retinoic acid in the metabolic process. This ingredient also comes from the great ?acneologist? Dr. James Fulton, who was one of the co-inventors of the original Retin-A. Retinyl propionate is the ingredient that Dr. Fulton used in his skincare product line, Vivant Pharmaceuticals.
Retinyl propionate is a less irritant form of Vitamin A than retinoic acid, and unlike retinyl palmitate, it is a small enough molecule that it can penetrate through the epidermis into the dermis. In the dermis, it promotes synthesis of new collagen, and also inhibits the enzyme collagenase which destroys the healthy collagen around a pore that is infected with acne, often causing a scar.
It is generally agreed upon that retinyl propionate is an effective acne treatment, especially when combined with other acne-fighting ingredients like mandelic acid and niacinamide; but there are conflicting studies about whether or not it actually fights the extrinsic signs of aging.
A 2004 study conducted by Procter & Gamble examined whether or not retinyl propionate combined with niacinamide effectively combated visible signs of photo-damaged skin (hyperpigmentation, leathery texture, and wrinkle). This in vitro study concluded that this vitamin combination did in fact improve the texture and wrinkles associated with photo-aged skin, without irritation.
However, a 1998 double-blind randomized placebo-controlled study of 80 subjects determined that ?although minimal trends towards improvement occurred, no statistically significant differences between the effects of the retinyl propionate cream and the placebo preparation were apparent for any of the clinical, histological or profilometric parameters of skin photoageing?.
So, for acne, I think retinyl propionate is a viable treatment ingredient, especially when combined with other beneficial skin nutrients; but for anti-aging benefits alone, you might want to try something else. Something like?
Retinaldehyde, also known as retinal (not retinol) is one of the trendiest Vitamin A derivatives on the professional skincare product market today. It is the direct precursor to retinoic acid in the metabolic process, and like retinyl propionate, it is a much less irritant form of the vitamin.
Retinaldehyde was researched extensively in the late 1990s to determine its efficacy for treating acne, photo-damaged skin, preventing premature aging, and treating broken capillaries. It was also closely examined for any signs of creating irritation or inflammation, as well as potential photosensitivity. The research indicated that retinaldehyde is the best form of Vitamin A for treating acne because unlike retinoic acid, it has a direct antibacterial effect on the p. acnes bacteria without destroying the healthy flora in the skin and mucus membranes thereby compromising the skin?s immune system in the long run. Furthermore, it does not cause the level of irritation to the skin as retinoic acid or topical retinol does, nor does it increase the skin?s susceptibility to UV damage.
In terms of anti-aging, retinaldehyde has demonstrated improvements in the texture and wrinkles of photo-aged skin. Additionally, it has been shown to increase dermal thickness by remodeling collagen and elastin.
Retinaldehyde is also the only form of Vitamin A that is usable on patients with rosacea. Other retinoids are much too irritant for the constantly hypersensitive and inflamed skin associated with rosacea. However, retinaldehyde does not cause the irritation that the other forms cause, and it also reduced facial redness and visible capillaries. People with rosacea often have very thin, fragile skin as a result of the condition. Retinaldehyde, in combination with other skin nutrients can help restore dermal thickness, increase circulation, and reduce inflammation.
Why is this form of Vitamin A less irritant, but still as effective as retinoic acid? The main reason is that unlike retinoic acid, retinaldehyde can be stored in the skin, and will only produce the amount of retinoic acid the skin needs, when it needs it. Any ?leftover? retinaldehyde will be stored for future production of retinoic acid. Therefore, there is no excess retinoic acid oxidizing and creating harmful free radicals in the epidermis. Sounds like the perfect ingredient, doesn?t it? It?s great, but it does still have some issues. The biggest issue is that it is a big molecule and cannot penetrate the epidermis unless it is encapsulated in a liposomal delivery system, in which case it penetrates through to the dermis via the hair follicles. This is an expensive process. Additionally, like other retinoids, retinaldehyde has stability issues and will degrade if it is exposed to sunlight or certain temperatures/humidity levels. Certain methods of bottling and packaging can help, but unless the product is loaded with preservatives (which will compromise the ingredient, irritate, and inflame the skin on their own), shelf life is a big issue. A little birdie did tell me that a stabilized form of retinaldehyde may be on its way in the near future, and as soon as I hear news of it, you will read it here.
My final thoughts on Vitamin A in skincare:
I think I made pretty clear that I do not advise the usage of any form of retinoic acid, really for any reason. I know the seemingly fast results in treating acne or photo-aged skin are attractive to those who are dealing with these conditions, but the irritation and inflammation that will occur as a result, as well as the potentially serious side effects are not worth any short-term improvement. Acne (even very severe acne) and photo-aged skin can successfully be treated without these overly aggressive forms of Vitamin A.
Topical retinol is too unstable and irritant to be worth any possibility of benefit, and retinyl palmitate is just not active enough to cause any improvement in the skin. It is also typically found in lower-priced products that do not use high enough quality or quantity of the ingredient, or proper formulation.
That leaves retinyl propionate and retinaldehyde. I have not had any personal or professional firsthand experience with retinyl propionate, but I have several colleagues who swear by it for treating acne, and several experts in the industry prefer it as well. New research is always happening and science constantly gives us new enhancements to our tried and true vitamins and other nutrients so I am very excited to see what the future will bring for Vitamin A in skincare.
*Vitamin A Metabolism diagram?by Vladislav Andriashvili – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=27485145; Retinyl propionate structure image?by Ed (Edgar181) – Own work, Public Domain, https://commons.wikimedia.org/w/index.php?curid=17606497.