Why is Vitamin A so important for understanding the health of our skin? Our skin naturally contains considerable amounts of vitamin A, which is stored in the epidermis. This outer layer of the skin stores vitamin A in the form of retinyl esters. Vitamin A is a vital part of our body’s natural ability to ward off ultraviolet rays, but this natural defense degrades with exposure to the UVA and UVB spectrum, necessitating daily application as well as the use of sunscreen for protection. Without this protection acute UVA irradiation naturally occurring in the sun (concentrated in tanning beds) can cause erythema, sunburn cell formation, direct long-term DNA damage, and common forms of skin cancer. Treatments containing molecules like retinyl palmitate are the future means of reducing these disastrous effects due to its photo-protective properties that prevent photo-carcinogenesis, as compared to other artificial sunscreens.
Various studies have been carried out to assess the effect of retinyl palmitate, the predominant form of epidermal vitamin A, to prevent the interactions between UVA and DNA. The study by Tran et al, 2002, showed that retinyl palmitate was actually an efficient UV. Furthermore, sunscreens containing retinyl palmitate were shown to inhibit UVB induced erythema in human skin that is a common feature after exposure in the sun, resulting in redness or rash – the common sunburn. The study observed onset of erythema 24 hours after a single UVB exposure that is used to determine SPF of sunscreens as it is considered to be a marker of injury or inflammation. The human subjects were either pretreated with 2% retinyl palmitate, or commercial sunscreen with 20 SPF, or retinyl palmitate vehicle and then exposed to 2 or 4 MED(Minimal Erythema dose) UVB. The results showed that both topical retinyl palmitate 2% and SPF 20 sunscreens strongly inhibited the development of erythema.
Creams containing retinyl palmitate are being increasingly used because they absorb all the energy of ultraviolet rays, preventing damage to the inner workings of our body including chromophores such as DNA, flavins, or NADPH. Without including this essential ingredient, other sunscreens are not only ineffective in storing vitamin A in epidermal retinyl esters, but they are also unable to protect the DNA from UV damage. Retinyl esters are endogenous substances,substances naturally created in our tissues and cells, which can be applied to skin in order to efficiently filter solar UV radiation. Due to their lower toxicity, physiologic regulation, and other biological properties they are the best choice in prevention of skin cancer. Few Creams contain retinyl palmitate in sufficient concentrations to achieve this effect, so check your labels, and do your research!
Comments