The body isn’t one for subtleties. Eat greasy food late at night and chances are your stomach will have informed you of your bad decision by morning. Internal batteries running low? Your eyes (and under-eye circles) will tell the story of late nights and lack of sleep. As for lackluster skin, brittle nails and dull hair—they’re screaming out for nutritional changes.

Regarding the latter, it’s important for retailers to recognize these signs when concerned customers ask about restoring outward signs of good health. Such outer beauty woes can be aided by both topical and internal cosmeceuticals. With the help of this dynamic duo and other healthy habits, the body will happily regain the glow of good health.

Get it, Got it, Good
The phrase “beauty from within” is more than just a platitude. It represents a strong, growing category of inner nutraceuticals intended to help improve skin, hair and nail health from the inside with targeted nutrition. Importantly, it’s a message that consumers get.

A January 2008 Pink Report entitled, “The Age of Naturals,” indicated cosmeceutical supplements, in particular, resonate well with consumers—especially those who purchase natural/organic products. The report noted that “72% of women who buy natural and organic beauty products believe in the concept of beauty from the inside out, compared with 49% who buy mainstream beauty products. Consumers are looking for food and beverage products that support a healthy lifestyle and overall physical appearance” (1).

According to Eileen Sheets, managing director of Bioforce USA, Ghent, NY, women are savvy when it comes to health and beauty and she agrees with the Pink Report: consumers have easily grasped the concept of oral cosmeceuticals (especially for anti-aging purposes). “Demand has changed in the past few years in one simple manner: it has skyrocketed, and we believe the usage and forging of product loyalty bonds will only continue,” she says.

It’s no accident that the timing of this market’s upswing is happening now. The public is more educated than ever about the benefits of cosmeceuticals. Frank Assumma, director of marketing at Natural Health Science, Hoboken, NJ, points to the writings of authorities like Dr. Nicholas Perricone as contributors to the category’s popularity. He explains that Perricone’s theory (described in The Wrinkle Cure) of inflammation’s relationship to aging “was considered revolutionary at the time and it is now accepted in the scientific community and by consumers.”  Assumma adds that consumers now understand that environmental toxins like ultraviolet (UV) light and cigarette smoke damage the skin with premature aging. He says the change in mindset is so dramatic that women understand “skin rejuvenation does not need to involve invasive treatments, or the use of neurotoxins or even radical surgery. It can be achieved with natural cosmeceuticals in both oral supplements and topical treatments.”

Therefore, if you’re wondering which products are responsible for this growing market, check out the needs of the baby boomers. Items for skin hydration, skin elasticity, wrinkle care, UV protection and other anti-aging products top the list of hot cosmeceuticals. The baby boomers were the first generation to truly embrace the idea of supplementation and natural health care so they are a natural fit for the cosmeceuticals market. “Most of them were introduced to natural supplements and this is a natural, next step for them in the health industry,” says Grace Lyn Rich, director of trade marketing at Futurebiotics, Hauppauge, NY. “They’re used to turning to it for other conditions, whether it be for joints, cardiac conditions or whatever.”

These men and women aren’t the only consumers looking for anti-aging products; teens, too, are using these products. Linda Miles, L. Ac. D.O.M., vice president of derma e Natural Bodycare, Simi Valley, CA, points out, “Younger consumers are paying more attention to their skin and becoming more educated on the effects of sun, pollution and free radical damage. They are gravitating more towards anti-aging products that will help protect their skin.”

The upswing in consumer interest and new product launches may also be due, in part, to newly published information about cosmeceutical ingredients, says David Djerassi, consultant to LycoRed Corp., Orange, NJ, and president of Intrachem Technologies, New York, NY. And this trend will grow as we see new studies for oral and topical cosmeceuticals in print. “In the next few years, you’re really going to see an evolution in new product introductions because I think people want to have both types of products to support them. They know good food and good nutrition will give you certain features when it comes to healthy, youthful skin, nails and hair. Now, the data are coming out and I think we’re on the right track,” he says.

Achieving More Together Than Apart
The last time a customer asked you about skin hydration products, did you walk him/her to your personal care section? Or, did you recommend your supplement aisles?

The best tactic, say industry insiders, is to do both. In fact, the concept of using oral and topical cosmeceuticals together is very much in line with the ideals of the natural products industry. This market segment is based on the idea that we want to support whole-body health, not just a symptom. Those who specialize in cosmeceuticals will tell you that unhealthy skin, hair and nails reflect an imbalance in inner health. Using topical and oral cosmeceuticals together can help from multiple angles. Says Dean Mosca, president of PNI, Kearny, NJ, “The appearance of aging (wrinkles, dry skin, brittle nails, lackluster hair) really stems from within. It bears repeating that a healthy lifestyle and diet help keep the signs of aging at bay. Topical emollients and moisturizers are excellent to immediately hydrate skin that has been exposed to sun or wind, and those that can effectively deliver nutraceuticals into the body via the skin are that much better.”

Physiologically, the pairing of topical and oral cosmeceuticals makes perfect sense, according Stephen Strassler, founder and president of Reviva Labs, Inc., Haddonfield, NJ. “Although some new peptide and growth factors are ‘messenger elements’ that can influence deeper skin reaction, we should remember that topical skin products primarily relate to the epidermis—about 20% of skin. The other 80%, the dermis, needs internal nutrition and supplementation,” he explains.

Using the two methods together can, in some cases, make the topical product work even better, says Strassler. He offers some examples: “alpha lipoic acid tablets and alpha lipoic acid cream, or vitamin C complex tablets (which feature rutin and citrus flavanoids) along with Reviva’s Spider Vein & Rosacea Day Cream (which features the same elements and have shown excellent results for that hard-to-treat skin problem).”

The benefits of each method are significant, but unique. Oral cosmeceuticals are intended to offer systemic support that will, in turn, help with outer appearance over time. “We feel very strongly that there is a place for dietary supplements. You need an adequate supply of vitamins and minerals to maintain youthful and healthful beauty,” says Rich, who adds, “If you don’t have adequate nutrition, it’s going to show in your looks. We’re big advocates in making sure you’re getting adequate vitamins and minerals to support your [outer appearance].”

Topicals are a great way to achieve results quickly, in many respects, such as with hydration or protection from ultraviolet light. Says Lakshmi Prakash, Ph.D., vice president of innovation and business development with Sabinsa Corp., Piscataway, NJ, “The topical product provides a local benefit to the location where it is needed the most…By improving your general health (inside) it will reflect as healthier skin and by adding a topical application (outside), we also provide a local therapy to a specific part of the skin.”

Miles notes that although there are benefits for the skin when taking a vitamin and/or antioxidant supplement orally, “applying antioxidants topically is the fastest way to help support and protect your skin.” She refers to Lester Packer, founder of Packer Lab at UC Berkley (which specializes in antioxidant research) and author of The Antioxidant Miracle, who stated, “Although taking oral supplements will help to boost the amount of antioxidants in your skin, the direct application of antioxidants to the skin is a much faster way to increase the level of antioxidants.”

Miles recommends “taking an antioxidant-rich supplement, consuming a balanced diet with fresh fruits and vegetables (and excluding foods that create an unhealthy impact on the body) and applying topical antioxidants to help support your body and prevent and reverse the signs of aging.”

Other products truly walk the oral–topical line. For example, vitamin E supplements have long been a staple in heart health and other products. On the skin, consumers often use this vitamin for keeping skin healthy. Says Scott Smith, marketing director at A.C. Grace Company, Big Sandy, TX, “For the past 46 years our customers, both healthcare professionals and consumers, have used our Unique E Mixed Tocopherols as a topical by cutting the end off of the softgel cap and applying it directly on wounds, burns, stretch marks, around their eyes and on their skin. The interest in a good vitamin E topical has always been there, and now with the push for all-natural products in the industry, topicals have become a much more requested product line.” The company now offers its Unique E Mixed Tocopherols in a one-ounce pump bottle for this reason. “Not only is it a topical, but it is a dietary supplement of the very same E in our capsules,” says Smith.

The nutrient may not work in exactly the same way, though. Says nutritionist Rob Stuart, Ph.D., advisor to A.C. Grace Company, “Vitamin E (alpha tocopherol) is an essential nutrient and functions primarily as an antioxidant within cell walls, while the other tocopherols, primarily gamma tocopherols, have other functions in the body besides antioxidant activity. Therefore, mixed tocopherols taken orally will provide a different mechanism of action when compared to using them for topical application.”

Overall, retailers should be aware of the opportunities to cross-merchandise these topical and oral cosmeceutical lines. “Oral and topical go hand in hand. There’s no question,” says Djerassi. “We’ve shown that if you take oral supplementation and then you use it topically, you can augment the performance of the product. You really get the benefit of what you sometimes cannot get with topical application.”

Stores should try selling topical and oral cosmeceuticals in the same aisles and post shelf talkers about how both types of products support the other. Be sure to communicate that outer beauty is a synergy of healthy habits and can be assisted by oral and topical products as a unit.

What’s On the Shelf?
Shield the Skin. In Return to Beautiful Skin, Myra Michelle Eby, founder and president of Mychelle Dermaceuticals, LLC, Frisco, CO, writes, “The sun fascinates me. Sunshine is vital to life and yet its power can do so much damage” (2). The sun emits heat, but it also gives off UV radiation that causes sunburn and suntans; over time, these burns and tans make the skin thick, dry and lacking in collagen and elastin. “That’s what causes skin to look like leather,” says Eby (2).

About 90% of all visible signs of aging (such as wrinkles, age spots and broken capillaries) are caused by sun damage, which damages collagen and elastin. These supportive fibers and proteins keep skin firm, but as they dry out from photodamage or with age, the skin sags (2).

Therefore, UV protection is a major need for shoppers in the cosmeceuticals category. Often, topical moisturizers include SPF ingredients to hydrate while protecting from sun damage. For example, derma e’s Anti-Aging Moisturizing Complex, SPF 15 is infused with SPF ingredients and antioxidants like green tea and olive oil, which are said to have “potent antioxidant and anti-inflammatory properties,” says Miles.

In addition, this derma e formula, along with several other oral and topical cosmeceuticals for UV protection, includes astaxanthin. According to Miles, “Astaxanthin is 500 times more powerful than vitamin E in neutralizing free radicals. It has the ability to shut down free radicals, protect the skin from UV damage and environmental stress and is 1,000 times more effective than both beta-carotene and lutein in protecting skin from exposure to UV light.” Astaxanthin specialists say the nutrient helps lengthen the time it takes before one becomes sun burned. Cyanotech, a major supplier of BioAstin astaxanthin, found in a human clinical trial that taking astaxanthin orally for two weeks “significantly increases the duration of UV light exposure required to create sunburn.”

Oral cosmeceuticals for UV protection are very important for those who often spend time in the sun without sunscreen. For example, women often use cosmetics and moisturizers that have added UV protection, but most men don’t use such products. As a result, they (and anyone else who goes outside without UV protection) have no defense against the sun. For this reason, Djerassi suggests consumers take a daily supplement that helps protect against UV rays. For example, LycoRed’s LycoMato lycopene extract “is proven to protect the skin when taken orally for six to 10 weeks,” says Djerassi who adds that by using supplements with this ingredient, “you can build a very nice reservoir [of it] in the skin.” Such protection from the inside may also be beneficial to the hair, as most natural sunscreens are not appropriate for conditioners and shampoos.

Another photoprotective ingredient (oral and topical) is the PPL-240 antioxidant from Gourmetceuticals. This extract from Polypodium leucotomos works by “inhibiting free radical generation, preventing photodecomposition of both endogenous photoprotective molecules and DNA, and preventing UV-induced cell death,” according to Garrett Lindemann, Ph.D., chief executive officer/chief science officer of the company, who states, “Extensive clinical research of both oral and topical formulations has demonstrated its photoprotective ability to protect cell damage caused by the sun’s UV-A and UV-B rays, while supporting its safety and efficacy.” The ingredient, he adds, helps reduce skin sensitivity to UV radiation, reduce the severity of sunburn and minimize photoaging.

Some tactics for UV protection involve controlling inflammation. Immune cells live in the dermis layer of our skin and act as watch dogs that initiate a solid response against anything considered harmful to the body, according to Frank Schönlau, Ph.D., director of scientific communications at Horphag Research. “‘Low-level’ inflammation resulting from minor UV-exposure or oxidative harm such as from cigarette smoke causes immune cells to generate more molecules which harm the skin. A particularly harmful inflammatory molecule is the matrix metalloproteinase (MMP),” he explains. This enzyme breaks down collagen and elastin and takes a toll on skin elasticity, says Schönlau and notes, “Ozone as a typical oxidant air pollutant speeds-up the generation of inflammatory molecules. An extract of the French maritime bark (like Pycnogenol from Natural Health Science) may have an anti-inflammatory effect that can help on this front.” According to a study conducted at the University of Arizona, Tucson on student volunteers, supplementation with Pycnogenol helped prevent sunburn. Animal studies, according to NHS, indicate that oral and topical use of Pycnogenol help prevent photoaging.

Miles adds that this nutrient also helps on other fronts such as stabilizing the capillary system and supporting microcirculation. “It enhances texture and elasticity, reduces irregularities and works with vitamin C to help rebuild collagen and elastin fibers,” she explains. Finished topical products that include Pycnogenol include derma e’s Age-Defying line (Day Crème, Night Crème and Eye Crème), which are also made with other botanicals like astaxanthin. According to Miles, these products “help guard against environmental stress and diminish fine lines and wrinkles for younger looking skin.”

Plump, Firm and Smooth. For many women, fine facial lines may put a wrinkle in their plan to conceal the signs of aging. Wrinkles can be caused by numerous factors like dehydration, but plumping the skin may reduce the appearance of fine lines (1). The following is a list of various botanical ingredients often using to improve skin quality:

• Oral supplements of lycopene, according to Dejerassi, were shown in a University of Germany study (on LycoMato) to improve skin thickness, smoothness and density after 10 weeks.
   
• According to Miles, retinol (vitamin A) is one of the “most effective exfoliants used for skin renewal.” Topical use may lessen the appearance of fine lines, crow’s feet and wrinkles. Derma e offers an anti-wrinkle moisturizer (Vitamin A and Green Tea Crème) with 20,000 IU of retinyl palmitate per 100 grams for maximum cell renewal action, Miles notes. Green tea, an anti-inflammatory and an anti-bacterial agent, is infused into the formula because it may be beneficial for skin that has been damaged by the sun or the environment over time.
   
• Hydroxyproline is an interesting amino acid for skin care because it combines two key amino acids involved in collagen formation: hydroxy and proline. According to Djerassi, studies on the nutrient showed “dramatic moisturization even during the winter” after using hydroxyproline orally for eight weeks. “It penetrates the skin and helps with collagen formation because it activates the fibroblast cells that generate collagen,” he says. Studies conducted on Lumistor, a branded hydroxyproline distributed by Kyowa Hakko, have shown that either topical or oral use of L-Hydroxyproline can enhance skin collagen formation and increase moisture retention. “Lumistor is beneficial as a cosmeceutical and a nutraceutical ingredient for maintaining healthy skin and is recommended for topical use in creams and lotions, or as a dietary supplement,” said Karen E. Todd, director of marketing for Kyowa Hakko USA in a press statement about the ingredient, which was a finalist for the NutrAward in 2008.
   
• Hyaluronic acid (HA) is another staple of the skin moisturization and plumping category. HA holds more water than any other molecule and is key for keeping collagen hydrated, healthy and plump (3).  According to Strassler, “HA is the intercellular gel that stores water and feeds it to the skin cells. In adding moisture to skin, it fights dryness and helps reduce the look of lines and wrinkles.” Unfortunately, the body’s natural stores of HA become depleted with age, so it’s important to replenish supplies with oral supplementation and topical creams. Topical products include derma e’s hyaluronic acid product line; Nonie of Beverly Hills’ moisturizers, cleansers and sun block; Purity Products’ Hyalastin, Hyalastra and Line Erase; Reviva Labs’ InterCELL Day Cream and Night Gel, high-potency HA Serum and Ampules; and Hyalogic’s Episilk serums, creams, lotions, masks for wrinkle, dark circle and age spot care as well as conditioners and shampoos for maintaining scalp and hair health. Branded ingredients include BioCell’s Collagen II (a matrix of collagen type II, chondroitin sulfate and HA); and Injuv from Soft Gel Technologies, Inc.
   
•  An HA-support ingredient is Natural N-Acetyl Glucosamine (NAG) (such as Hyalurogluco from Kaneka), which is clinically proven to increase hydration and smooth out the skin, according to Robert Barry, Ph.D., director of scientific affairs at Kaneka Nutrients, L.P., Pasadena, TX. “Upon ingestion, NAG reaches the skin cells and greatly enhances your internal production of HA…This is very important as HA is a very large molecule which cannot be easily absorbed if applied topically or ingested,” he explains.
   
• Ceramide also works with HA to help reinforce the skin’s barriers to toxins from the environment and keep moisture in. As HA and ceramide levels decrease, skin can become dehydrated and more prone to wrinkling. Cerenew, an ingredient for Soft Gel Technologies, combines ceramide, its branded HA complex (Injuv) and biotin “to reduce the appearance of fine lines and wrinkles, brighten the complexion, and tighten sagging skin,” according to a company brochure.
   
• Other collagen-supporting ingredients include peptides like palmitoyl pentapeptide and acetyl hexapeptide, which, according to Miles, help stimulate collagen production, thus improving elasticity and relaxing facial muscles. She notes that the former “tells the skin to synthesize new key components such as collagen and to restructure itself. The repair mechanism results in thicker skin, better skin tone and fewer wrinkles.” The latter, Miles explains, “relaxes facial muscles, smoothes away wrinkles and discourages the formation of new lines.” Both are included in derma e’s Peptides Plus formulas.
   
• Strassler agrees that peptides and growth factors are key for anti-wrinkle products and adds some others. Palmitoyl peptide3 (found in Reviva’s Peptides and More Cream along with marine oligopeptides and coconut endosperm) can lessen the depth and length of wrinkles, he says. Growth factors, Strassler adds, are the “newest cosmeceutical category and include Tissue Growth Factors (TGF) and Epidermal Growth Factors.” Featured in Reviva’s TGF Beta-1 Cream is a new palmitoyl tripeptide3, a TGF that helps skin tissue appear more toned and healthy. “This particular TGF communicates signals to dermal cells to stimulate circulation. Thus, new cells can, once again, receive adequate nutrients from capillaries that feed the birth layer of the epidermis (where new skin cells are formed). It takes time for these growth factors to do their job but with improved cell quality, skin can achieve a more youthful-complexion,” says Strassler.
   
• The omegas 3-6-9 are also said to be good for skin health. One omega that gets less attention is omega-7, which is also supportive of the skin. Says Rich of Futurebiotics “Omega-7 is another fatty acid that is very nourishing to skin [and helps with] hydration of skin membranes.” Futurebiotics’ Omega-7 Plus formula (with biotin and silica) sources its omega-7 from macadamia nut oil, sea buckthorn oil and Gevuina avellana nut oil.
   
• Vitamin E is key for locking in moisture and protecting against free radical damage. According to Jim Capps, general manager for A.C. Grace Company (which offers Unique E topical and oral vitamin E), “Vitamin E has been shown to assist with soothing the skin, reinvigorating skin cells and many other positive dermatological attributes.”

• According to the American Academy of Anti-Aging Medicine, alpha lipoic acid (ALA) can help replenish important vitamins and can reduce the inflammatory effects of UV radiation. Reviva Labs features ALA and vitamin C Ester in its topical formulas along with numerous other botanicals. The reason, says Strassler, is that “scientists recognize that because the fatty part of the cell, the cell wall or membrane, contains the richer source of electrons (the free radical objective is to steal an electron), fat- and water-soluble ALA protects the membrane as well as the cell interior.” He adds that ALA’s ability to recycle vitamins C and E and CoQ10 is important because these antioxidants not only protect against future damage, they help AHA “fight past damage—helping lessen fine lines and wrinkles, and reducing under-eye puffiness.” In fact, according to Barry of Kaneka (maker of KanekaQ10), “CoQ10 is one of the most powerful lipid-soluble antioxidants known, preventing oxidative and free-radical damage to lipids, cells and DNA…It is also a critical component of cellular energy production, providing the spark for over 90% of your ATP generation in every organ of your body, including the skin. It literally re-energizes your skin back to youthful conditions by restoring levels of this critical co-enzyme, which naturally drop off with age.  It has also been clinically shown to have UV protective benefits.” Vitamin C Ester (another key ingredient in several Reviva Labs serums, creams and lotions) helps support ALA. Says Strassler, “It’s a more potent form of vitamin C, created by adding palm oil to ascorbic acid. It’s non-acidic and also fat soluble; particularly beneficial in helping prevent cross-linking of collagen.
   
• Miles agrees that ALA and C Ester are important in anti-aging products and adds that like Reviva Labs, derma e also uses DMAE to help “improve skin elasticity, reduce facial sag and firm skin.” According to Miles, studies on DMAE shows that it helps lessen the appearance of fine lines and wrinkles; C Ester helps protect skin cells from free radical damage, reduces wrinkles, and helps firm skin by building collagen and elastin.
   
• Other botanical ingredients for hydration and skin plumping include Cococin and Forslean CG from Sabinsa. Cococin is a nutrient-rich coconut water that “has been used internally and topically as a refresher and moisturizer,” says Prakash. Forslean CG helps remove fat under the skin and rebuild aging and damaged fibroblasts. “Therefore, there will be an increase of collagen and elastin (lean body mass) which constitute the foundation of healthy skin,” she says.
   
• Celadrin, a blend of esterfied fatty acids from PNI, has been shown in studies to enhance the lipid structure of cell membranes, which may help cells to rapidly repair and regenerate. According to PNI’s Mosca, study participants said their facial skin was more firm and hydrated after just three weeks. In addition, he adds that “the study showed Celadrin had penetrated every layer of the skin, and helped to improve the hydration, resiliency, elasticity and firmness of the skin.”
   
• Studies on Pycnogenol indicate it may help lighten dark age spots. Says Schonlau, “The synthesis of pigments in skin cells, the melanogenesis, was significantly and dose-dependently decreased by inhibition of the key enzyme involved (a specific tyrosinase).” Assumma adds that antioxidant ingredients like alpha-lipoic acid and Pycnogenol may “help fight the free radical damage that can cause age spots and ‘graying’ of the skin.”
   
• Finally, mushroom formulas play a key role in anti-aging regimens. Tremella, for example, has long been used in China as the Mushroom of Beauty, according to information in the Maitake Products Web site. The company offers various oral supplements with tremella such as its Collagen Pearl (with collagen for skin suppleness and pearl powder for healthy skin) as well as its Aquamella skin cream.

Hair and Nails. The hair and the nails are two of the most susceptible places to poor nutrition, and they quickly show discoloration and brittleness as a result. One key nutrient to keep in mind in this category is biotin, which may help strengthen brittle nails (4). According to the Linus Pauling Institute, several clinical trials have shown significant improvement in nail strength, and one showed a 25% increase in fingernail thickness. Djerassi explains that the reason may be that oral biotin given over the course of six to 10 weeks may help in the formation of keratin in the nails.

Other nailcare help may come from herbal products. For example, Himalaya USA’s NailCare supplement combines guggul, arjuna and ashwagandha for nail structure support, nail metabolism and nail strength, according to the company’s Web site.

Along with brittle nails often comes dull, brittle hair and sometimes hair loss. Losing one’s hair is often traumatic. “People suffering from thin hair and hair loss often experience considerable psychological strain and seek dermatological help, in spite of the limited range of therapies currently available,” says Sheets (whose company, Bioforce, distributes Hubner Original Silica Gel). “Silicic acid preparations are among those products attributed with an effect on the structure of hair.” Bolstering this statement are the results of a 2007 phase-II pilot study. Researchers in this trial determined the hair volume of women (n=55) given an oral silicium gel (15 mL) over six months increased the thickness of their thinning hair by 13%.

Other silica supplements include Alta Health Products’s Sil-X Silica formulation, the Viviscal line for hair loss (supplements as well as topical products for daily maintenance) from The Aurora Group, and others.

But the best nutrition for skin, hair and nails must also include a strong daily, multinutrient base, Rich of Futurebiotics points out. For this reason, the company formulated two supplements (Hair, Skin & Nails and Hair, Skin & Nails for Men) that are daily multivitamins plus additional nutrients to support hair, skin and nails. Says Rich, “We recognize that you need a good multi-base, so we’re giving it to you in a formula with all the extras.” Such “extras” on top of the multivitamin include biotin, calcium, silica from horsetail extract, gelatin, cysteine and methionine. WF

References

1. The Benchmarking Company, The Age of Naturals (Washington, DC, 2008).
2. M.M. Eby, Return to Beautiful Skin (Basic Health Publications, Laguna Beach, CA, 2008).
3. B. Sardi, How to Live 100 Years Without Growing Old, (Here and Now Books, San Dimas, CA, 2002).
4. Linus Pauling Institute, Micronutrient Information Center, http://lpi.oregonstate.edu/infocenter/vitamins/biotin/.

WholeFoods Magazine, September 2008