Antioxidant Supplements: An Important Intervention In Skin Anti-Aging

James Meschino DC, MS, ROHP
In recent years scientific studies have shown that antioxidant vitamin and mineral supplements provide skin cells with important protection against ultra-violet light damage.  Antioxidant nutrients, such as vitamin C, vitamin E, beta-carotene, lycopene selenium, zinc, and manganese have been shown to concentrate within skin cells after oral consumption, and participate in chemical reactions that help curtail the free radial damage associated with accelerated skin aging (photo-aging), wrinkling, aging spots and skin cancer. As such, skin care professionals should be aware of the mechanism of action though which ultra-violet light generates free radicals within skin cells, as well as the research that suggests that all adults should optimize their antioxidant nutritional status as an additional means to slow skin aging, wrinkling and help block steps that are linked to skin cancer development.

The Formation Of Free Radicals Within Skin Cells
Let’s first address how ultra-violet light generates free radicals within the skin. Developing skin epidermal cells below the surface contain molecular oxygen (O₂), which can be transformed into a free radical with absorption of photon energy from ultra-violet light. Essentially, photon energy from the sun or tanning beds injects molecular oxygen within skin cells with an extra electron, which converts oxygen into an aggressive free radical known as the superoxide anion. In some instances oxygen may absorb two electrons and become converted into hydrogen peroxide (HOOH), which can travel to the nucleus of the cell, and then be further converted into two hydroxy radicals (HO- plus –OH) upon donation of an electron from a transition metal (iron, copper). Together, the superoxide anion and hydroxy radicals cause extensive free radical damage to various parts of the cell, including the cell membrane, enzymes, lipids, proteins and the DNA of the cell.  This damage is linked to accelerated aging of the skin and skin cancer development. Wrinkling is linked to free radical damage that occurs in the dermis as collagen fibers become cross-linked (twisted) along with increased elastin and fibrin synthesis and displacement and structural changes to the glycosaminoglycans (dermatan sulfate and hyaluronic acid).

Like other cells in the body, epidermal cells contain antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase), which quench and neutralize free radicals within skin cells. However, these enzymes cannot prevent ultra-violet induced skin damage by themselves and require additional support from the nutritional antioxidants mentioned above. Studies reveal that supplementation with antioxidant nutrients, at levels beyond which can be obtained from food alone, provide epidermal cells and the dermal layers with significant protection from free radicals generated from exposure to ultra-violet light. As such, in blinded, placebo-controlled studies, antioxidant supplementation has been shown to reduce skin inflammation, sunburn reaction, DNA-damage, protein oxidation and alterations to the dermal layers, upon exposure to ultra-violet light, compared to the control group who were given the placebo supplement.

Additionally, nutritional antioxidants are known to be incorporated into the skin surface lipids, and provide added antioxidant protection to the skin by preventing the build up of peroxides. Peroxides are another type of free radical that can be formed in the skin when fats in skin surface lipids are exposure to ultra-violet light.

Thus, scientific evidence strongly suggests that, in addition to reducing exposure to ultra-violet light, wearing protective clothing, and using protective suntan lotions, individuals should also be advised to ingest a high potency antioxidant-enriched supplement each day to help optimize protection against premature skin aging, skin cell mutations, and skin wrinkling.

Antioxidant Daily Dosages:
The body of evidence suggests that the following antioxidant dosages be ingested daily as an integral part of lifelong skin care management:

Vitamin C – 1,000 mg (500 mg, twice daily)

Vitamin E – 400 IU (natural source as vitamin E succinate)

Beta –carotene – 10,000 IU

Selenium – 100- 200 mcg

Zinc – 15 mg

Manganese – 5 mg

Lycopene Extract – 6 mg

It is possible to find these dosages within a single high potency multi-vitamin and mineral supplement for the sake of convenience. As well, other nutrients contained within a multi-vitamin also provide synergistic benefits to skin health. For example, the B-vitamin niacin has been shown to help reduce sun-damage to the skin by enabling skin cells to generate more ATP energy, which in turn provides additional energy to repair damage to their DNA, after exposure to UV-light. Many B-vitamins and other nutrients are also required for normal skin cell development and for the conversion of essential fatty acids into prostaglandin series-1 and series 3, which make skin cells softer and smoother, and slow skin aging.

References:

1. de Gruijl, FR. Adverse effects of sunlight on the skin. Ned Tijdschr Geneeskd 1998; 142 (12): 620-5
2. Eberlein-Konig, B et al. Protective effect against sunburn of combined systemic ascorbic acid (vitamin C) and d-alpha-tocopherol (vitamin E). J Am Acad Dermatol 1998; 38(1): 45-8
3. Podda, M et al. UV irradiation depletes antioxidants and causes oxidative damage in a model of human skin. Free Radic Biol Med, 1998; 24 (1): 55-65
4. Emonet-Piccardi, N et al. Protective effects of antioxidants against UVA-induced DNA damage in human skin fibroblasts in culture. Free Radic Res 1998; 29 (4): 307-13
5. Firkle, T et al. Antioxidants and protection of the skin against the effect of ultraviolet rays. Cas Lek Cesk 2000; 139 (12): 358-60
6. Pugliese, PT. The skin’s antioxidant systems. Dermatol Nurs 1998; 10 (6): 401-16; quiz 417-8
7. Keller, KL, Fenske, NA. Uses of vitamins A, C, and E and related compounds in dermatology: a review. J Am Acad Dermatol 1998; 39 (4 Pt 1): 611-25
8. Stahl W et al. Carotenoids and carotenoids plus vitamin E protect against ultraviolet light-induced erythema in humans. Am J Clin Nutr 2000 Mar; 71 (3): 795-8

9.Shukla, A. Depletion of reduced glutathione, ascorbic acid, vitamin E and antioxidant defense enzymes in a healing cutaneous wound. Free Radic Res 1997; 26 (2): 93-101