Vitamin C (L-ascorbic acid) is a water soluble antioxidant that ranks as one of the most abundant and used antioxidants in both the skin and body. It has many functions and uses, both internally and externally, but its primary function is to protect tissues from oxidative stress. Unfortunately, humans do not produce their own Vitamin C and must obtain it from other sources regularly. Studies suggest that oral or dietary intake of Vitamin C and other antioxidants may not be sufficient for maintaining optimal levels of these antioxidants in the skin. A daily dietary intake of a variety of antioxidants is important for health but topical application can have a more direct effect on the skin, increasing antioxidant levels to protect against the constant assault your skin fights and protects you from.
As we age the concentration of Vitamin C in the dermis and epidermis layers of the skin begin to decrease. Vitamin C is also used and depleted in great amounts when exposed to ultraviolet light, pollutants such as cigarette smoke and exhaust, and times of body stress. This decline results in an increase in photo-aging and the development of tissue damage by free radicals. Regular topical applications of Vitamin C can maintain the levels of these important antioxidants.
Many animal and human studies have been done recently to explore the effects of antioxidants in the body. Particularly, the skin care industry has inspired a better understanding of the role they play with the skin. Vitamin C has been shown to do some amazing things mostly as a result of its defense against oxidizing free radicals. Almost every study, however, has shown better results when in combinations with other antioxidants, particularly lipophilic antioxidants like Vitamin E. Damaging free radicals can have oxidative effects on both water and lipid soluble tissues so it is important to have the defense of a combination of antioxidants.
The most notable benefit of using Vitamin C in skin care is its ability to limit the damage done by UV exposure. Vitamin C (especially in combination with Vitamin E) prevents the acceleration of aging caused by free radicals from ultraviolet light damaging structural tissues. Vitamin C also plays a role increasing the synthesis of those structural tissues and the amount of fibroblast present in the skin that are responsible for the formation of collagen. Vitamin C also helps in reducing the immunosuppressive effects of UV light and preventing inflammatory or erythemic responses to exposure.
Not only does Vitamin C protect us from aging but it can help reduce the damage that has already happened, decreasing wrinkles and reversing some of the structural damage caused by UV rays.
Other important features of Vitamin C topically include the reduction of TEWL (trans epidermal water loss), allowing your skin to stay more hydrated, the lightening of skin by reducing melanin oxidation, reducing inflammation of acne lesions and decreasing general skin redness and sensitivity.
Many factors are involved in optimal absorption of topical applications of Vitamin C and not all products are created equally. Vitamin C is water soluble and the top layer of the skin (stratum corneum) is designed to reduce exposure especially from water soluble ingredients. This layer of the skin also thickens as we age. It’s important for better absorption of Vitamin C products to incorporate a good exfoliation regimen on a regular basis to reduce the obstruction of this layer.
The concentration of Vitamin C in a product greatly lends to it’s efficacy as well as a product’s PH and packaging. Maximum absorption of Vitamin C can be found at concentrations of 20% free form L-ascorbic acid. Greater and lesser concentration decreased absorption.
Products above a PH of 4 have little effect on the skin while products with a PH lower than 2.5 cause potential irritation. The most optimal PH being around a 3 for penetration of Vitamin C products.
Vitamin C is very unstable in products and should be exposed to as little oxygen and UV light as possible in order to preserve its potency. An overexposed Vitamin C solution can even become more harmful than helpful due to oxidation. Look for packaging that is airtight and limits repeated exposure oxygen and UV light.
Overall Vitamin C in combination with other antioxidants, particularly Vitamin E, can create amazing change in the skin. It can also protect and reinforce the skin’s ability to function in an environment that continually assaults the skin; ultimately resulting in healthier, more youthful skin.