Topicals are a Hot Topic
If you’re into reading about nutrition or have happened to run across a few tidbits in the news, you’ve probably heard that consuming foods that contain vitamins C, E, and D may have a positive anti-aging effect. You may have heard that drinking green tea increases beauty and health benefits. Eating foods high in the antioxidant lycopene (tomatoes, watermelon, ketchup, grapefruit, papaya) may prevent cardiovascular disease, certain cancers, type 2 diabetes, osteoporosis, and even male infertility. Well now there’s reason to believe that rubbing some of these same nutrients may be just as beneficial as taking them in orally.
You may be aware that your skin is the largest organ in your body. Made up of several layers and some hair, skin is your primary defense when it comes to environmental forces like temperature regulation, pollution, radiation and other pathogens. Often if you eat something that doesn’t jive withy our immune system or digestive system, a reaction will manifest on your skin – in the form of a rash, hives, pimples, etc. The same can be true when you accidentally or intentionally apply a new cosmetic or substance to your skin – you may get a positive or less than positive reaction.
But not everything that comes in contact with your skin is fully absorbed into your body. Absorption happens when the topically applied substance breaks the skin barrier and travels to the bloodstream. Your body then has to decide whether this is a good thing or a bad thing and either try to assimilate the substance, excrete (get rid of) the substance or the substance can accumulate, which isn’t the best scenario. Penetration is a bit different in that, the topically applied substance gets into the top layer of the skin, but doesn’t actually break through the bottom layer to get absorbed into the bloodstream. In this case, there would not be a systemic effect. Many factors affect whether or not a substance will penetrate or be absorbed. Thinner skinned areas (inner thigh, forearm, under the eyes, breasts), are more likely to absorb chemicals than thicker (palms and soles of feet).
In a recent study from Milan, Italy, vitamin E (mixed tocopherols and tocotrienols) was rubbed on subjects’ skin. The skin was exposed to ultraviolet light (UV) for half an hour and then evaluated for redness. Topical application of vitamin E protected the skin from the radiation-induced photosensitivity. It may even be more effective when combined with vitamin C topically for sun protection. In other news, topical vitamin C (10% solution or greater) reduces risk for skin wrinkling, redness, and skin cancer. Topical vitamin C also encourages collagen production. It appears that L-ascorbic acid is the form of vitamin C needed to penetrate skin layers. Topical application of green tea has been shown to reduce skin cancer risk and redness.
Dr. Wendy Wong, out of the University of Hong Kong writes, “The parent compound of vitamin A is not absorbed by the skin. Its derivatives, retinoic acid is a lipid soluble molecule known to affect cell growth, differentiation, homaeostasis, apoptosis and embryonic development. The third generation retinoids (such as adapalene) is less irritating and more photo-stable than the first and second generation retinoids of Retinol, Tretinoin and Isotretinoin. Their comedolytic properties and excellent follicular penetration enable them to be the mainstay for anti-acne treatment. They also increase epidermal turnover, stimulate new blood vessel formation and promote collagen remodelling, hence repair sun damage and reduce wrinkles of sun- exposed skin.” Okay, that’s a mouthful. In lay terms, it seems that topical vitamin A from the grocery store may not be well absorbed and you would have to go the more pharmaceutical route with a retinoid prescription for acne or wrinkles.
Vitamin K has been getting more attention lately. It may be applied topically after laser procedures to help minimize bruising and improve healing times. Phytonadione and menaquinone are two active forms of vitamin K that are used for supplements and cosmetics.
Topical application of Vitamin D is most commonly used for psoriasis and itching.
Topical capsaicin (from red pepper) is used to help relieve pain of arthritis and herpes zoster (used only on closed skin).
As always we recommend you speak to your primary care doctor or dermatologist before experimenting on yourself with new forms of treatment. Especially where skin is concerned, you want to rule out anything suspicious – a new growth, a wound that isn’t healing, a rash of unknown origin, changing spots, etc – and get checked out thoroughly on a regular basis.