A multitude of over-the-counter skin care products – from sunscreens and moisturizers to cosmetics – tout vitamins and antioxidants as ingredients. What importance do vitamins play in skin and skin health, and do these products really work?
Skin is damaged and aged by exposure to ultraviolet radiation (UVR) from sunlight. UVR interacts with our skin to produce unstable, toxic byproducts called reactive oxygen species (ROS), which are largely responsible for the aged appearance of skin including wrinkles, discoloration (ie, "sun spots"), and rough or thickened texture. These negative effects of UVR on skin are known as "photoaging." The idea behind fortifying many skin care products with vitamins lies in the fact that many vitamins are very effective antioxidants, or molecules that reduce ROS and therefore fight photoaging. Not all vitamins play a role in skin health, however, and different formulations of the same vitamin are not necessarily equally effective. Here's what you should know about vitamins and how they combat photoaging to help you choose the best products for healthy, youthful skin.
Vitamin A derivatives are a staple in every dermatologist's practice. Prescription-formulated derivatives of vitamin A, called retinoids, have well-established effects in combating sun-induced discoloration and fine wrinkles, as well as multiple other skin conditions such as acne, psoriasis, and several types of skin cancer. Natural vitamin A comes in 2 forms in everyday foods: retinol can be found in liver, milk, and eggs, while carotenoids, a precursor to retinol, can be found in carrots, tomatoes, and other fruits and vegetables. Beta-carotene is an example of a carotenoid and has antioxidant properties. Vitamin A also plays a role in increasing the amount of collagen – a major substance that gives skin firmness and support – present in the skin. Vitamin A derivatives in over-the-counter products come in many different forms, including retinols, retinaldehyde, and retinyl esters. Of these, retinols are probably the most effective in the treatment and prevention of photoaging. Even so, they are probably not as effective as prescription-only retinoid formulations.
In addition to being a potent antioxidant, vitamin C – also known as ascorbic acid – plays an essential role in the production of collagen and elastin, which are important supporting structures in the skin. With age, these substances degrade, leading to loose skin and wrinkles. Thus, vitamin C can help strengthen skin as well as prevent and repair damage caused by ROS. It is important to consider, however, that many topical formulations of vitamin C may not necessarily be in a form that can penetrate the skin enough to have beneficial effects. Therefore, oral supplements or dietary sources of vitamin C (such as citrus fruits) are likely to have a greater effect on skin health than topical formulations.
Vitamin E is a common ingredient in a variety of over-the-counter skin care products, including moisturizers and cosmetics. Vitamin E plays a role in protecting the outermost layer of skin cells, the cell membrane. It is also a potent antioxidant, and in mouse studies it has been shown to protect skin against sunburns before UV exposure. Vitamin C plays a role in vitamin E stores, and therefore the effects of both of these important vitamins may require that they be used together. It is important to note also that high levels of oral vitamin E can actually be harmful, and therefore all vitamins should be taken at recommended levels.
The B complex vitamins are a group of 8 vitamins including thiamine (B1), riboflavin (B2), niacin (B3), pyridoxine (B6), folic acid (B9), and cobalamin (B12). They are found frequently in a variety of foods, including potatoes, bananas, turkey, and tuna. Many breads and pastas are folate-enriched due to FDA requirements. While all the B complex vitamins play different and important roles in health and metabolism, niacin, or B3, has perhaps the most promising effects in terms of skin health. Oral niacin is currently used as a prescription medication for improving cholesterol levels and has a role in fighting heart disease. In animal studies, niacin has been shown to increase supporting structures in skin and prevent skin cancers caused by sun exposure. Small studies have also shown promising results for topical niacin in lightening sunspots and decreasing fine wrinkles in humans.
Vitamins play a critical role in maintaining skin health. Vitamins A, C, E, and B3 in particular have shown promising results in studies against photoaging, and therefore there may be great benefits from supplementing our diets with vitamins. It is important to keep in mind, however, that many studies are ongoing, and the appropriate formulations and amounts needed to achieve these benefits have not been established in most cases. A daily multivitamin is a safe and simple measure to supplement one's diet without concern for possible harmful effects of vitamin overdose. And while vitamins may protect the skin against damage from the sun, the most important step we can take to protect our skin from UVR damage is the regular use of sunscreens and protective clothing and hats.
*Reference: Zussman J, Ahdout J, Kim J. Vitamins and photoaging: Do scientific data support their use? Journal of the American Academy of Dermatology 2010; 63:507-25.