The skin is the largest organ in the body, weighing approximately 20 pounds. It is a highly proliferative tissue and is prone to various diseases, defects, infections and insults from chemical, physical and ultraviolet light sources.1 Modern-day nutrition and biochemical research has demonstrated that specific dietary nutrients significantly affect the health and appearance of the skin and can slow the biological processes associated with skin aging.
Specific dietary agents and certain supplements are known to enhance the health and appearance of the skin by providing photo-protection against sun damage, improving immune function at the skin level, reducing changes linked to skin-cancer development and providing therapeutic bioactive agents that assist in the treatment of many skin conditions, such as psoriasis, eczema and acne.1-2
Along with hair and nails, skin is the fastest growing and most superficial tissue in the body. As such, it has a high demand for nutrients in order to continuously replenish itself with rapidly developing immature skin cells from the layers below. Even a marginal deficiency of vitamin A, the carotenoids, vitamin D, vitamins B1 and B2, niacin, pantothenic acid, biotin, folic acid, vitamin B12, vitamin E, vitamin C or essential fatty acids can result in impaired development of skin cells that manifests itself in skin that is less smooth, prone to lesions, less elastic and more prone to accelerated aging.1-3
In the pursuit of healthy-looking skin, many individuals limit their approach to the application of topical skin creams and lotions. However, studies indicate that the addition of specific nutrient supplementation and a healthy diet to a skin care regimen can significantly enhance skin texture and appearance beyond what is attainable from the use of topical creams and lotions alone.2-3 In fact, the color and luster of the skin can be an important clue to underlying nutritional problems. The skin should be soft, moist and relatively wrinkle-free, neither too dry nor too oily.
Excessive cross-linking of collagen caused by exposure to free radicals promotes wrinkling. That is why smokers are three times as likely as nonsmokers to develop premature wrinkles, and the reason those who have over-exposed their skin to sunlight also reveal premature skin wrinkling. Of course, antioxidant supplements and antioxidant-enriched skin creams can help to reduce this form of skin damage.
As reported by R Hoffman, the medical director of the Hoffman Center for Holistic Medicine in Manhattan, an inner facial consisting of changing to a healthier diet, better elimination and supplementation with vital skin nutrients, including essential fatty acids, can result in dramatic improvements in skin appearance in three to four months.3 The evidence is now strong and consistent that the outer beauty of the skin and the effective treatment of damaged skin and other skin disorders requires a comprehensive strategy that must include the intake of optimal levels of certain vitamins, minerals and essential fatty acids.2
Topical Skin Nutrients
Before examining the relationship between dietary nutrients and skin health, it is important to address the value of incorporating certain nutrients into topical creams and lotions. Recently, there has been much attention given to the use of lotions containing phytoestrogens. A review of this evidence indicates that the use of topically applied estrogen, (as well as hormone replacement therapy) and the use of natural progesterone by postmenopausal women may improve the skin's texture and appearance to a significant degree. However, estrogen replacement has been shown to increase the risk of breast cancer and influence the risk of other health conditions, which must be factored in to the decision-making process.4-11
In regards to the topical application of phytoestrogens (plant-based estrogens), studies reveal that the transdermal absorption of the soy isoflavones genistein and diadzein is possible from studies that used specific oils (e.g., olive oil) as a transdermal chaperone agent. It appears that with repeated use, these phytoestrogens are captured in the skin, where they may exert a positive effect on skin cell development and texture. At this point, it is too premature to make any definitive statements in this regard and thus, the topical application of phytoestrogens as an intervention for skin health should be regarded as experimental at this time.12
Other nutrients, however, are well-established as topical agents that may be considered for use to protect the skin from free-radical damage and improve the health of the skin in various ways. This list would include the antioxidants vitamin C, vitamin E and selenium, as well as other health-promoting and protective nutrients such as zinc oxide, green tea extract, witch hazel, aloe vera and milk thistle, which have all demonstrated impressive outcomes in clinical and experimental studies when used as topical agents.1
Nutritional Supplements And Healthy Skin
Oral ingestion of certain vitamins and minerals has been shown to be of proven value in the prevention and treatment of many skin condition. It is a fundamental consideration in lifelong skin health and maintenance, and a cornerstone of skin anti-aging practices.
Antioxidants and Free Radicals: Premature aging of the skin, genetic damage to skin cells and underlying melanin pigment are known to result from free-radical damage, which most commonly occurs due to overexposure to ultraviolet light from solar radiation (sunlight). Free radicals generated from cigarette smoking and alcohol consumption can also damage the skin in a similar way.
Free-radical damage hastens the process of skin aging and wrinkling and creates mutations that are known to lead to the development of skin cancer (basal cell carcinoma, squamous cell carcinoma and melanoma). Presently, non-melanoma skin cancer is the most common malignancy in the United States; the estimated lifetime risk of developing malignant melanoma in the U.S. rose from one in 250 in 1981 to one in 87 in 1996.1-3, 13-14
Cumulative lifetime sun exposure and decreased protection from the Earth's shrinking ozone layer are considered to be the primary culprits for these disquieting statistics. Too much sun exposure also leads to sunburn, which is an inflammation of the skin caused in part by the sunlight's activation of free-radical molecules. Excessive sun exposure also impairs the skin's genetic material (DNA and RNA) and immune function, which further increase the risk of skin cancer. Therefore, avoiding overexposure to sunlight (and other known sources of free radicals), wearing protective clothing and using antioxidant-containing sunblock creams and lotions are prudent strategies to minimize risk of premature skin aging and skin cancer.1,3,6
In addition to these factors, recent studies have indicated that the use of antioxidant supplements can further help to protect the skin from free-radical damage and age-related changes linked to premature wrinkling and cancerous mutations. A double-blind, placebo-controlled study in human subjects demonstrated that subjects taking vitamin C (2,000 mg per day) and vitamin E (1,000 I.U.) supplements had significantly less free-radical damage to their skin after UV-light exposure than did subjects not given the antioxidant supplement regime. They also showed significantly less sunburn reaction.2,15
Further, it has been shown that free radicals (especially sun exposure) deplete the skin of its antioxidant defenses quite rapidly, further increasing the requirement for nutritional antioxidants to replenish these important cellular antioxidants.9 Other laboratory studies reveal that selenium, zinc and N-acetyl-cysteine supplementation can also defend skin cells against free radicals from UV-light.10 Intensive investigation in this area of study strongly suggests that the daily supplementation of vitamins A,C,E, beta-carotene, selenium and zinc, at levels above those typically consumed from food alone provides the skin with additional and possibly essential antioxidant defenses to help slow skin aging; and lends important support to other skin cancer prevention initiatives.2-3,8,16-22
B Vitamins and Skin Health: Virtually all B vitamins are required at sufficient doses to ensure healthy development of skin cells. In fact, deficiencies in many B vitamins directly result in various types of skin conditions, skin diseases and alterations in the normal appearance of the skin.23-24 Even marginal deficiencies of B vitamins can produce chronic skin lesions that are not treatable with topical agents alone.
For instance, nasolabial seborrhoea is known to result form marginal deficiencies in niacin, vitamin B6 or vitamin B2. Hyperpigmentation (color of skin changes first to red, then to brown) can result from niacin deficiency. Angular stomatitis (redness, cracking and flaking at the corners of the mouth) can result form a marginal deficiency of vitamin B2, vitamin B6, niacin or iron.25 Supplementation with the appropriate doses of specific B vitamins can reverse these conditions if a B-vitamin deficiency is a contributing cause of the problem, as is often the case.
In addition to these findings, human studies reveal that folic acid and/or vitamin B6 supplementation has been effective in treating acne vulgaris. B-complex vitamin supplementation has been used successfully in the treatment of eczema (atopic dermatitis) in conjunction with essential fatty acids and hydrochloric acid supplementation. Some patients with psoriasis respond favorably to supplementation with folic acid and/or vitamin B12, and patients with seborrheic dermatitis have been shown to improve with supplementation of biotin (a B vitamin), folic acid and/or vitamin B12. Investigation into this area demonstrates that suboptimal B-vitamin status can give rise to dermatitis (skin inflammation conditions), as well as lack of skin smoothness, seborrheic-type scaly lesions and/or irregular pigmentation.26
Certain B vitamins (B6, B2) also participate as co-factors in the synthesis of prostaglandin hormones that, in part, determine the smoothness and texture of the skin.27 More recently, niacin (vitamin B3) has been shown to help prevent skin damage or photo-aging induced by sunlight (ultraviolet light) by increasing the cellular energy required by skin cells to repair free-radical damage and preserve their immune function. These experiments suggest vitamin B3 supplementation may be an important aspect of preventing cancerous changes to skin cells and is involved in slowing the process of photo-aging of the skin over our lifetime.28
Unfortunately, data from the National Health and Nutrition Examination Survey II revealed that as a daily average across the U.S. population, 80 percent of Americans ingest less than the recommended daily allowance (RDA) for vitamin B6, 45 percent ingest less than the RDA for vitamin B1, 34 percent ingest less than the RDA for vitamin B2 and vitamin B12, and 33 percent ingest less than the RDA for vitamin B3.29 Moreover, the RDA values were not designed to represent optimal intake levels, but rather as levels of intake to guard against overt deficiency states.30 Thus, the RDAs are by no means the desired level of intake to maximize health and guard against degenerative and age-related diseases.
By all accounts, the daily use of a B-50 complex vitamin may be considered an important strategy to enhance and maintain the healthy appearance of the skin, aid in the treatment of various skin conditions, prevent the development of B-vitamin deficiency states that produce skin lesions and diseases, and help combat the underlying metabolic processes associated with photo-aging of the skin and skin cancer development.
TABLE 1 Common Skin Problems And Supplements That Help
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Look for part 2 of this article, including complete references, in the Jan. 15 issue.
Click here for more information about James P. Meschino, DC, MS.