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From The October 2000 Issue of Nutrition Science News
Antiaging Products for Skin, Hair and Nails
How vitamins, antioxidants and fruit acids keep people looking young
by C. Leigh Broadhurst, Ph.D.
Believe it or not, those expensive daily moisturizers and thick night creams that mainstream consumers so faithfully apply may be not only worthless but may actually be making them look older. That's because heavy and prolonged use of many conventional cosmetics (e.g., mineral oil moisturizers, face makeup, harsh detergent shampoos, benzalkonium chloride hair conditioners, nail polish and nail extensions) prematurely ages the skin, hair and nails.
This long-term damage occurs as a result of skin irritations or allergic reactions such as hives and itchy rashes. Even if the acute reaction subsides, persistent exposure to the irritant continues to cause damage, inflammation and abnormal growth in the underlying skin layers. Moreover, thickening and abnormal accumulation of elastic fibers, glycosaminoglycans (polysaccharides) and mast cells (large tissue cells) occur in the lower layers, just as it does after chronic ultraviolet irradiation of the skin.1 In short, the skin is prematurely aging from the chronic inflammatory response to synthetic chemicals.
Luckily, there is now a wealth of well-designed natural products available that do not induce this aging process and which may actually confer a performance advantage to the external body by rendering it less susceptible to the effects of aging. These natural cosmetics, which contain ingredients such as antioxidants, orthosilicic acid and fruit acids, hold a great deal of potential in terms of anti-aging principles and are much gentler on the body than their synthetic counterparts. The key to finding the right product is in understanding the actions of its active ingredients. Below is a listing of some of the most effective natural cosmetic constituents.
Components for Healthy Skin
Vitamin A Because topical vitamin A (retinol) is not stable in cosmetic preparations, it must be added in its rentinyl palmitate form—retinol and oxygen are linked (esterified) to the fatty acid palmitic acid. Retinyl palmitate has the ability to increase skin elasticity and decrease skin roughness and the peroxidation of skin lipids.2 In one research study, various skin creams containing 5 percent retinyl palmitate (vitamin A) and 10 percent alpha-tocopheral acetate (vitamin E) were shown to increase skin moisturization and cellular renewal and to decrease skin wrinkling when tested on five females ages 22 to 43.3 Although no difference was shown between the two vitamins, as both together were added or not added, it can be supported that either or both will have these results, with some synergy if both are used. Furthermore, the cream that demonstrated the best results was a liposome preparation.
Liposomes are microscopic lipid vesicles with exterior walls prepared from phospholipids (i.e., phosphatidyl choline, phosphatidyl ethanolamine) and an interior that is a separate material. The advantage of liposome formulations is that they enhance the ability of the contents to penetrate the outer layer of the skin.4 For example, most water-soluble compounds (including potentially beneficial botanical antioxidants) cannot readily enter the skin because it tends to shed water and strongly prefers fat-soluble compounds. However, if encapsulated in a liposome, a water-soluble combination is able to pass through the skin. Liposomes also regulate the release of contents (such as vitamin A) so that metabolism keeps pace with release.4
Most cell membranes in the body are principally made up of phospholipids; however, the outer layer of the skin is composed primarily of ceramides. Ceramides are compounds that lack phosphate groups and are made up of fatty acids linked to fatty amino alcohols. Liposomes prepared with ceramides are particularly well absorbed but expensive and are primarily reserved for drug delivery, or intensive facial treatments such as under-eye creams.5
Vitamin C (ascorbic acid) is a water-soluble vitamin that, when applied topically, can directly benefit the skin as an antioxidant, anti-inflammatory and skin-lightening agent. It is not stable in cosmetic preparations in the ascorbate form, however, which is the form typically used in dietary supplements.6 For example, a clinical study showed that ascorbic acid reduced inflammation after laser facial skin resurfacing when 10 percent ascorbic acid was applied in a non-cosmetic water solution but not in a cosmetic cream.7 Nevertheless, vitamin C can be made more stable and cosmetic-soluble—and hence more bioavailable—by esterification with a fatty acid, phosphate or similar derivative.8
Vitamin E When applied topically, forms of vitamin E including alpha-tocopherol, alpha-tocotrienol and gamma-tocotrienol have been shown to rapidly penetrate the skin and migrate to the areas near the sebaceous glands.9 Vitamin E is considered to protect against ultraviolet light damage and skin lipid peroxidation, reduce fine lines and wrinkles, and delay the progression of skin aging.10 In one study, a skin cream containing 5 percent natural d-alpha-tocopherol was shown to improve skin moisture in 12 subjects after nine weeks of use, but had no effect in a short 150-minute standard test.11 Apparently vitamin E needs to be absorbed and maintained in a certain concentration in the skin to exhibit a moisturizing effect.
Inerestingly, it's hypothesized that the long-term improvement in moisture brought on by vitamin E use is a consequence of its antioxidant properties. In other words, vitamin E is believed to prevent and repair oxidative damage to skin barrier lipids, thus allowing them to do their job properly. This mechanism may also apply to vitamin A, vitamin C and botanical antioxidants and provides a rationale for formulating daily skin treatments with antioxidants. Pycnogenol, derived from oligomeric proanthocyanidins,12 bilberry (Vaccinium myrtillus),13 ginkgo (Ginkgo biloba),14 and licorice (Glycyrrhiza glabra)15 have also been used successfully as topical antioxidants and found to speed the healing of wounds and skin that have been damaged via circulatory problems.
Bioavailable Silicon Blood vessels, bone, cartilage, hair, nails and skin are all composed wholly or partially of connective tissue, made up of proteins (e.g., collagen, elastin) and protein-sugar complexes such as chondroitin sulfate. The trace element silicon (Si) is concentrated in the connective tissue and is thought to play a role in cross-linking connective tissue structures, there by helping to create their unique tough-but-flexible strength. A lack of silicon is known to reduce normal growth and repair of the skin, hair and nails.16 However, studies show that silicon supplementation has delivered few benefits.16 The reason for this in most cases is that a nonbioavailable silicon source has been used.17 Silicon is a nonmetallic element that is very reactive. It occurs naturally almost exclusively in silicates, the geologic rock-forming minerals. Although silicates are the most abundant materials on earth, they don't provide a bioavailable form of dietary silicon. Moreover, silica, often used as a dietary supplement, is a polymeric silicon-hydroxide-oxide-water complex from hard stone, such as quartz, that has anywhere from two to trillions of silicon atoms, and is also very poorly bioavailable.17 On the other hand, orthosilicic acid, which consists of only one Si bonded to four hydroxides instead of oxygen, is the form of Si that is found in our bloodstream. Therefore, stabilized orthosilic acid is the only form of supplemental silicon that has been shown conclusively to be bioavailable for humans.18,19 Silicates, silica gel, colloidal silica, clays, horsetail (Equisetum arvense) and most foods don't contain the orthosilicic acid form of silicon.
A research study conducted at the University of Antwerp in Belgium that used supplemental stabilized orthosilicic acid showed it to increase collagen synthesis in calfskin by 15 percent compared with controls.20 All 49 calves in the study received some silicon intake in the form of their normal daily food, while half the calves' silicon was increased by 4.9 percent in the form of stabilized orthosilicic acid. Remarkably, this mere 4.9 percent orthosilicic acid significantly increased silicon levels in the calves' bloodstream as well as increased collagen. Although these results cannot prove the topical benefit of silicon, they demonstrate the positive correlation between serum silicon concentrations and collagen concentrations in cartilage, thereby implying such advantages.
Alpha-Hydroxy Acids (AHAS) are now common ingredients in skin care products such as masques, scrubs, lotions and skin lighteners, all of which are designed to improve the appearance of the facial skin. AHAs are also called "fruit acids" because they occur naturally in many fruits. These substances differ from simple acids in that an OH (hydroxyl group) is located on the "alpha" carbon adjacent to the final carbon.
When alpha-OH is added to acetic acid—the acid found in vinegar—it produces glycolic acid. This compound is formed as a by-product of sugar refining and is the most common and widely utilized AHA. Other popular AHAs are lactic acid (tomato juice, buttermilk); tartaric acid (wine, grapes); malic acid (apples); and citric acid (citrus fruits, pineapple).
When applied to the skin, AHAs increase the turnover rate of skin cells, improve skin moisture and help exfoliate the top layers of dead skin.21 This effect makes the skin look younger, tighter and fresher, and helps lighten freckles and dark spots. However, improvements in skin appearance largely come about because AHAs slightly irritate the skin. For example, the prescription "facial peels" given by dermatologists contain 50 to 70 percent glycolic and lactic acids; thus they are effective exfoliants, but can cause redness, irritation, and skin sensitivity. In contrast, inexpensive over-the-counter products contain only 1 to 10 percent AHA (usually also glycolic and lactic acids), so they cause less severe side effects but produce less noticeable improvements.
One way to enhance the effects of lesser concentrations of AHAs without increasing skin irritation or sensitivity is to add herbs. For example, in one study, galactoarabinan, a sugar polymer from the Western larch tree (Larix occidentalis), was added to an 8 percent lactic acid cream. Amazingly, only 2 percent galactoarabinan was needed to increase the exfoliation performance of the lactic acid cream by 80 percent after four days, and with no increased irritancy.22 In addition, topical application of white lupine (lupinus alba) reduced skin thinning associated with AHA exfoliation and enhanced the skin's natural restructuring process.23 Additional balanced herbal approaches utilize herbal fruits such as bilberry (Vaccinium myrtillus), grapes (Vitis) and sea buckthorn (Hippophae goniocarpa). Since such herbal extracts contain mixed AHAs along with phytochemicals that have antioxidant and anti-inflammatory effects, they are capable of normalizing the reactions of the skin's immune cells.24
Balancing the effects of AHAs is especially important for those who are using such products to combat serious skin conditions. Research has shown that AHA treatment has potential to improve skin diseases, such as psoriasis, ichthyosis and hyperkeratosis, characterized by extreme flaking and scaling.25 For such disease treatment, however, peels may need to be used regularly for years; thus, skin irritation can become a real concern.
Naturally Healthy Nails
Use of nail polish and remover, excessive dish and hand washing, household and industrial cleaners, swimming pools, and certain occupations damage and prematurely age the cuticles and fingernails. This damage manifests itself in brittle nails that break easily, or nails that split and peel. Damaged cuticles may be rough and sore, with hangnails and cuts.
A common myth is that nail polish protects nails. In fact, nothing could be farther from the truth. Nail polish, and especially nail polish remover, contains the harshest chemicals used in any cosmetic application. Nail polish remover strips natural fats from the nail and cuticle and damages its protein structure.26 Avoiding nail polish and nail tips or extensions and wearing rubber gloves when cleaning are excellent ways to protect one's nails.
Besides external precautions, I have seen four to six weeks of orthosilicic acid supplementation reverse nail and cuticle damage. Furthermore, essential fatty acids (EFAs) can help. Adding 46 g of omega-6 gamma-linolenic acid (GLA) will give even better results—sources include evening primrose (Oenothera biennis) or borage oil (Borago officinalis). In addition to taking the oils internally to speed healing, they can be rubbed into the nail bed each night. Both linoleic acid, another omega-6 EFA, and GLA are precursors for some of the ceramides that form the skin's protective barrier (skin includes the scalp and cuticles), and GLA may help resolve the inflammation associated with damaged cuticles, thereby promoting normal nail growth.27
Fortunately, the quality and number of natural beauty products containing ingredients such as vitamins A, C and E; silicon; and GLA is rapidly increasing. When it comes to improving both appearance and performance of the skin, natural ingredients are inherently superior to synthetic because they are much less likely to irritate the body's sensitive systems.28 Instead, these products work to prevent and ease the signs of aging.
Sidebars:
Hair Graying And Loss
C. Leigh Broadhurst, Ph.D., heads 22nd Century Nutrition, a nutrition/scientific consulting firm, and is the author of Diabetes: Prevention and Cure (Kensington Publishing, 1999).
References
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17. Jugdaohsingh R, et al. Oligomeric but not monomeric silica prevents aluminum absorption in humans. Am J Clin Nutr 2000;71:944-9.
18. Reffitt DM, et al. Silicic acid: its gastrointestinal uptake and urinary excretion in man and effects on aluminium excretion. J Inorg Biochem 1999;76:141-7.
19. Calomme MR, et al. Absorption of silicon in healthy subjects. In Collery P, et al., editors. Metal ions in biology and medicine, vol. 5. Paris:John Libbey;1998. p. 228-32.
20. Calomme MR, Vanden Berghe DA. Supplementation of calves with stabilized orthosilicic acid. Effect on the Si, Ca, Mg, and P concentrations in serum and the collagen concentration in skin and cartilage. Biol Trace Elem Res 1997;56:153-65.
21. Moy LS, et al. Glycolic acid peels for the treatment of wrinkles and photoaging. J Dermat Surg Oncol 1993;19:243-6.
22. Westman M. Galactoarabinan an exfoliant for human skin. Cosmet Toil 1999;114:63-71.
23. Closs B, Paufique J. White sweet lupine as a skin restructuring agent. Cosmet Toil 1999;114:75-82.
24. Kim HP, et al. Effects of naturally occurring flavonoids and biflavonoids on epidermal cyclooxygenase and lipoxygenase from guinea-pigs. Prost Leukot Essent Fatty Acids 1998;58:17-24.
25. Kostarelos K, et al. AHA and exfoliative skin diseases. Cosmet Toil 1999;114:43-50.
26. Falbe J, editor. Surfactants in consumer products: theory, technology and application. Heidelberg, Germany: Springer-Verlag;1987.
27. Broadhurst CL, Winther M. Evening primrose oil: pharmacological and clinical applications. In Mazza JG, Ooma BD editors. Functional foods: herbs, botanicals and teas. Lancaster (PA):Technomic Publishing;2000. p. 213-65.
28. Broadhurst CL. More than skin deep. Nutr Sci News 1999;4:524-8.
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