The Skinny On Skin

Unlike other organs of the body, skin nutrition can be enhanced by “direct deposit” through topical application of micronutrients, which can complement dietary acquisition and result in a stronger, healthier barrier to the world. Did you know that, when you look at a person, you are looking at dead skin? That would be the horny, keratinized outer layer called the stratum corneum. Keratin is a protein that helps to keep skin hydrated by preventing water evaporation. You might recognize it as the major component of wool, nails, rhino horns, and quill pens. The cells of the stratum corneum can also absorb water, which explains the puffiness and wrinkling you get in your fingers from sitting in the tub too long. Be glad this doesn’t happen all over. Sometimes, when your skin gets dry and itchy, you can see flakes of it when you scratch. That is the stratum corneum, part of the epidermis, which also contains the skin pigmentation chemical called melanin. Since people who look at you are seeing the walking dead, you might as well try to make it at least a little bit attractive.

Dry skin can be caused by harsh detergents and soaps, and by nutritional deficiencies, especially of essential fatty acids. Diet aside, at least for now, topical treatments can help to keep skin moist and pliable. There are no blood vessels in the epidermis to deliver nutrients to the stratum corneum, which usually prevents the passage of many types of molecules to layers below. Sometimes, though, a compound will pass through. Changes in temperature, air flow and humidity can pull water away from the skin and interrupt its integrity. If ignored, this can lead to more serious concerns, including cell damage and inflammation that perpetuate the condition. An important strategy is to address dry skin by maintaining the lipid components of what is termed the natural moisturizing factor.

The outer layers of the epidermis receive less nutritional support than underlying cells, hence the slowness and limitation of dietary interventions to offer positive effects. On the bright side, concentrations of nutrients in the skin can eventually be met through oral avenues. On the other hand, topical application may be more efficient, especially to ameliorate the ravages of photodamage (Pinell, 2003) (Zussman, 2010). Long before other insults were considered, poor nutrition was associated with changes in skin appearance, with the vitamin C deficit known as scurvy being among the first to be identified. Later associations, such as pellagra and ariboflavinosis, were found to be correctible through diet.

The topical use of micronutrients is a relatively new area of study (Boelsma, 2001). Much has been discussed and publicized about vitamins C, D, and E for skin health. Fatty acids have also been part of the conversation, and ceramides are slowly coming into the limelight (Coderch, 2003) (Guillou, 2011). This is warranted because the stratum corneum contains high levels of ceramides, constituting as much as half the total lipids, where they serve as a kind of glue that holds surface skin cells together.

But a not-so-new-kid on the block is gaining recognition for participation in the parade that leads to rescue of failing skin—the B-vitamins, 3 and 5. Nicotinamide (B3) is the amide of nicotinic acid, which is the form of niacin able to lower cholesterol and to cause flushing.  Nicotinamide is also called niacinamide, known to reduce glucose levels. Metabolically, nicotinamide is convertible to nicotinic acid. Though pharmacologically different, niacin/nicotinic acid and nicotinamide/niacinamide have the same vitamin activity. In a Japanese study conducted about a decade ago, it was found that topical nicotinamide is able to improve the permeability barrier of skin by stimulating the synthesis of ceramides, free fatty acids and cholesterol, with a subsequent decrease in transepidermal water loss (Tanno, 2000).

Not to be left out of the mix, panthenol likewise lends its magic to a topical lotion. Panthenol is the alcohol analog of pantothenic acid, also known as vitamin B5, that acts as a provitamin since it is quickly converted to vitamin B5. Only the D- form is biologically active, but both it and the L- form have moisturizing properties. In cosmetics, it may appear as DL-panthenol. Combined with niacinamide, this nutrient was shown to reduce a few obvious signs of aging skin, notably hyperpigmentation and redness. In a blinded study carried out in India, researchers found that subjects who applied such a lotion to the face daily for ten weeks experienced a significant reduction in redness and hyperpigmentation, an improvement in skin tone evenness, and positive effects on skin texture (Jerajani, 2010). Even in the absence of B5, the B3 application (niacinamide) alone was able to reduce the same negative features while simultaneously diminishing fine lines and wrinkles (Bissett, 2005) (Kawada, 2008).

Traditionally, vitamins have played the role of co-enzymes. You still need to eat food to give the vitamins something to work with. Several vitamins, however, assume the role of endocrine mimics. Biotin is one of these. Critical to carboxylation—replacing a hydrogen atom (H) with a carboxyl group (COOH), as in the oxidation of products that result from the decomposition of carbohydrates, fats and proteins—biotin also induces epidermal cell differentiation (Bolander, 2006), a process that helps to make new cells. This is especially noticeable in the health of fingernails and animals’ hooves, which become increasingly brittle and friable in the absence of biotin (Colombo, 1990) (Hochman, 1993).

We all know that exposure to the sun helps to make vitamin D. But we also know that too much exposure can cause the skin problems we’re trying to prevent or to rectify. The sun’s ultraviolet light is part of the invisible band of radiation. Most (~95%) of the UV that reaches the earth is the lower-frequency, longer-length UVA, sometimes called black light, that penetrates more deeply into the skin than UVB, but is less intense. UVA is the tanning ray that plays a major role in photoaging. UVB is responsible for sunburn and reddening, damaging the superficial layers of the epidermis. Both are culprits. Nicotinamide has been involved in cellular energy restoration after UV irradiation and is found to be immune protective, but riboflavin—vitamin B2—has similar virtue in that it is vital to cellular energy metabolism. Scientists who speculated that B2 could offer immune protection as well as B3 after insult by UV light were correct. Topical riboflavin protected against both wavebands (Diona, 2010) (Yoshikawa, 1999), and oral riboflavin can prevent dermatitis (Lo, 1984).

Taking a single B vitamin orally may have undesirable results; taking it as part of the entire complex, or adding it to the complex, is not a concern. Deficiency of B vitamins can be related to acne, cracked lips, dryness, wrinkles and an uneven complexion, among other dermatological (and metabolic) involvements. Avoiding these issues may be as easy as taking a supplement or finding a fortified lotion.

Bissett DL, Miyamoto K, Sun P, Li J, Berge CA. Topical niacinamide reduces yellowing, wrinkling, red blotchiness, and hyperpigmented spots in aging facial skin. Int J Cosmet Sci. 2004 Oct;26(5):231-8. doi: 10.1111/j.1467-2494.2004.00228.x.

Bissett DL, Oblong JE, Berge CA. Niacinamide: A B vitamin that improves aging facial skin appearance. Dermatol Surg. 2005 Jul;31(7 Pt 2):860-5; discussion 865.

Boelsma E, Hendriks HF, Roza L. Nutritional skin care: health effects of micronutrients and fatty acids. Am J Clin Nutr. 2001 May;73(5):853-64.

Bolander FF. Vitamins: not just for enzymes. Curr Opin Investig Drugs. 2006 Oct;7(10):912-5.

Coderch L, López O, de la Maza A, Parra JL. Ceramides and skin function. Am J Clin Dermatol. 2003;4(2):107-29.

Colombo VE, Gerber F, Bronhofer M, Floersheim GL. Treatment of brittle fingernails and onychoschizia with biotin: scanning electron microscopy. J Am Acad Dermatol. 1990 Dec;23(6 Pt 1):1127-32.

Diona L. Damian, Yasmin J. Matthews, Gary M. Halliday Topical riboflavin attenuates ultraviolet B- and ultraviolet A-induced immunosuppression in humans Photodermatology, Photoimmunology, & Photomedicine. Apr 2010; 26(2): 66-69

Guillou S, Ghabri S, Jannot C, Gaillard E, Lamour I, Boisnic S. The moisturizing effect of a wheat extract food supplement on women's skin: a randomized, double-blind placebo-controlled trial. Int J Cosmet Sci. 2011 Apr;33(2):138-43. doi: 10.1111/j.1468-2494.2010.00600.x.

Hochman LG, Scher RK, Meyerson MS. Brittle nails: response to daily biotin supplementation. Cutis. 1993 Apr;51(4):303-5.

Jerajani HR, Mizoguchi H, Li J, Whittenbarger DJ, Marmor MJ. The effects of a daily facial lotion containing vitamins B3 and E and provitamin B5 on the facial skin of Indian women: a randomized, double-blind trial. Indian J Dermatol Venereol Leprol. 2010 Jan-Feb;76(1):20-6. doi: 10.4103/0378-6323.58674.

Kawada A, Konishi N, Oiso N, Kawara S, Date A. Evaluation of anti-wrinkle effects of a novel cosmetic containing niacinamide. J Dermatol. 2008 Oct;35(10):637-42. doi: 10.1111/j.1346-8138.2008.00537.x.

Lacroix B, Didier E, Grenier JF. Role of pantothenic and ascorbic acid in wound healing processes: in vitro study on fibroblasts. Int J Vitam Nutr Res. 1988;58(4):407-13.

Lo CS. Riboflavin status of adolescents in southern China. Average intake of riboflavin and clinical findings. Med J Aust. 1984 Nov 10;141(10):635-7.

Mori K, Ando I, Kukita A. Generalized hyperpigmentation of the skin due to vitamin B12 deficiency. J Dermatol. 2001 May;28(5):282-5.

New D, Eaton P, Knable A, Callen JP. The use of B vitamins for cutaneous ulcerations mimicking pyoderma gangrenosum in patients with MTHFR polymorphism. Arch Dermatol. 2011 Apr;147(4):450-3. doi: 10.1001/archdermatol.2011.77.

Pinnell SR. Cutaneous photodamage, oxidative stress, and topical antioxidant protection. J Am Acad Dermatol. 2003 Jan;48(1):1-19; quiz 20-2.

Rajendran Kannan, MB BS MD and Matthew Joo Ming Ng, MB BS M Med Dip OccMed FCFPS Cutaneous lesions and vitamin B12 deficiency An often-forgotten link Can Fam Physician. 2008 April; 54(4): 529–532.

Tanno O, Ota Y, Kitamura N, Katsube T, Inoue S. Nicotinamide increases biosynthesis of ceramides as well as other stratum corneum lipids to improve the epidermal permeability barrier. Br J Dermatol. 2000 Sep;143(3):524-31.

Yoshikawa K. Vitamin and dermatology Nihon Rinsho. 1999 Oct;57(10):2385-9.

Zussman J, Ahdout J, Kim J. Vitamins and photoaging: do scientific data support their use? J Am Acad Dermatol. 2010 Sep;63(3):507-25.