by Robert M. Blair, Ph.D., and Aaron Tabor, M.D.
Nutritional cosmetics, or nutricosmetics, embrace the basic idea that what we eat impacts how we look. There is a rapidly growing interest in foods and dietary supplements that support healthier, better-looking skin, hair and nails. This is reflected in the growing number of product launches in the last few years. Recent reports by industry analysts indicate the nutricosmetic market was between $1.5 to 1.6 billion in 2008, and likely has tremendous opportunity for growth.1, 2
While many ingredients are currently being marketed for skin health and beauty benefits, many of these ingredients are marketed based on their antioxidant capacity and inferred skin benefits, though published research on their dermatological benefits is often lacking. Nonetheless, there are a number of dietary ingredients with scientific backing for their potential skin health benefits.
In our book,” Nutritional Cosmetics: Beauty from Within”, we attempted to put much of this information together in one place. In addition to data derived from cell culture and pre-clinical animal studies, we have included data from human clinical trials when possible. As one would expect, research into the benefits of nutricosmetic ingredients covers many functional endpoints, including skin moisturization, extracellular matrix support for firmer skin, antioxidant benefits, and support for a healthier complexion among others. A couple of these areas and ingredients shown to support them are discussed below.
Antioxidants that protect your skin
The potential benefits of many botanical ingredients are based almost solely on their antioxidant properties. While these ingredients are too numerous to mention them all, some of the better-known antioxidants include green tea, pomegranate, curcumin, resveratrol, coenzyme Q10 (CoQ10), carotenoids and superoxide dismutase (SOD). Human clinical trial data supports the skin health benefits of some of these antioxidant ingredients, including CoQ10 and olive fruit.
CoQ10 is endogenously made in the human body and plays a key role in ATP synthesis in the mitochondria and has important antioxidant effects. The skin health benefits of CoQ10 via dietary consumption were recently reviewed.3
In this review, the author reported oral administration of CoQ10 resulted in an increase in CoQ10 levels in the epidermis of mice, and dietary intake (60 mg/d) for two weeks reduced periorbital wrinkles.4
The benefits of CoQ10 for skin appearance are likely due to multiple mechanisms of action, including protection of keratinocytes from oxidative damage, stimulation of extracellular matrix protein production and proliferation of dermal fibroblasts.
Olive fruits and olive oil have been a part of the Mediterranean diet for ages. It seems we’ve been hearing a lot about the various health benefits of the Mediterranean diet recently and one of these benefits might include skin health. Olives are rich in a number of active constituents, including tyrosol, hydroxytyrosol, oleuropein and verbascoside. Clinical research suggests olive fruit extracts might reduce total body oxidative stress and reduce UV irradiation-induced skin sensitivity.5
In one study, consumption of 400 mg/d of an olive fruit extract for four weeks reduced the excretion of 8-isoprostane, a marker of oxidative stress, by nearly 50 percent. Additionally, consumption of an olive fruit extract (160 mg/d for four weeks) increased the minimal erythema dose by about 16 percent, indicating consumption of the olive fruit extract reduced the sensitivity of the skin to UV irradiation.
In addition to CoQ10 and olive fruit, there also is human data supporting the potential skin health benefits of dietary consumption of SOD, green tea, pomegranate and some of the carotenoids.
Maintaining a healthy complexion
Reports state a number of ingredients might support a healthier complexion, possibly through multiple mechanisms. A healthy complexion can be achieved through a variety of changes in skin appearance or function such as reducing skin discoloration, reducing skin reactivity and supporting skin immune function. Two ingredients that have been reported to support a healthier appearing complexion are soy and probiotics.
Probiotics are living microorganisms that can have a health effect when consumed in adequate amounts. These are most commonly thought of as used in yogurts; however, applications with probiotics appear to be a rapidly growing area of interest. Research into the skin health benefits of probiotics indicates that oral consumption might reduce skin sensitivity and support the skin’s immune function. In one clinical trial, oral consumption of a Lactobacillus johnsonii supplement for six weeks appeared to accelerate the recovery of the skin’s immune system compared to the placebo,6 while a second study indicated a combination of Lactobacillus paracasei and Bifidobacterium lactis decreased the skin’s neurosensitivity in women with reactive skin.7
Soy, both the protein and the isoflavones, have been used in numerous topical skin care products for years now, and there is a substantial body of in vitro and topical in vivo research showing the skin health benefits of soy. However, little work has been done to examine the benefits of dietary soy for skin health. Recent studies reported dietary consumption of soy can support healthier looking skin in both postmenopausal and premenopausal women. In a pilot study, postmenopausal women adding 20 g of soy protein containing 160 mg of soy isoflavones to their daily diet for six months saw a reduction in skin flaking and skin discoloration compared to women not adding soy to their diets.8 Similar results were observed in randomized, double blind, placebo-controlled study of premenopausal women.9
Future Research
To date, the vast majority of research into the benefits of dietary ingredients for skin health has either focused on determining the antioxidant potential of the ingredient or been conducted in cell culture systems and pre-clinical animal models. Very little research has been conducted in human volunteers. Of these human clinical trials, most of them have been relatively small. However, this early research has shown great promise for a number of ingredients. It is our hope that as new ingredients and products are developed, the appropriate research will be conducted, especially clinical trials of safety and efficacy. Consumers today tend to be very well informed and take their personal care seriously. Because of this, it has become even more important to conduct the appropriate research on new ingredients and finished products. We believe that the most successful products will be those with such supporting scientific evidence.
Robert M. Blair, Ph.D., is the research manager for Physicians Pharmaceuticals Inc. and manages the daily activities of the research and nutrition departments. Dr. Blair received his Ph.D. from Oklahoma State University in the field of reproductive physiology. Before joining Physicians Pharmaceuticals, he worked as an assistant professor of comparative medicine at the Wake Forest University School of Medicine where he examined the effects of dietary soy on cardiovascular health and cognitive function.
Aaron Tabor, M.D., is the CEO and medical research director of Physicians Pharmaceuticals and author of Dr. Tabor’s Slim & Beautiful Diet. A graduate of the Johns Hopkins School of Medicine, Dr. Tabor oversees all clinical research on Dr. Tabor’s Slim & Beautiful Diet plan, conducting randomized, double blinded, placebo-controlled studies at leading hospitals in the U.S. Areas of note include weight loss, skin/hair/nail appearance, energy, menopause, PMS, cholesterol, memory and diabetic health. He is also responsible for directing new product development based on clinical research results.
References:
1. Grammenou E. What’s next for cosmeceuticals and nutricosmetics? GCI Magazine, April 2009.
2. Beyer AM. Buying into functional foods. GCI Magazine, August 2009.
3. AshidaY. Inhibitory effects of coenzyme Q10 on skin aging. In: Nutritional Cosmetics: Beauty from Within, Tabor A, Blair RM (eds). William Andrew Applied Science Publishers/Elsevier, 2009, pp 199-215.
4. Ashida Y, Nakashima M, Kuwazuru S, Watabe K. Effect of CoQ10 as a supplement on wrinkle reduction. Food Style 2004; 8:52-54.
5. Cristoni A, Giori A, Maramaldi G, Artaria C, Ikemoto T. Olive fruit extracts for skin health. In: Nutritional Cosmetics: Beauty from Within, Tabor A, Blair RM (eds). William Andrew Applied Science Publishers/Elsevier, 2009, pp 233-244.
6. Gueniche A, Benyacoub J, Blum S, Breton L, Castiel I. Probiotics for skin benefits. In: Nutritional Cosmetics: Beauty from Within, Tabor A, Blair RM (eds). William Andrew Applied Science Publishers/Elsevier, 2009, pp 421-439.
7. Gueniche A, Benyacoub J, Breton L, Bastien P, Bureau-Fanz I, Blum S, Leclaire J. A combination of Lactobacillus paracasei CNCM I-2116 and Bifidobacterium lactis CNCM I-3446 probiotic strains decreases skin reactivity. J Invest Dermatol 2007; 102: S17.
8. Draelos ZD, Blair R, Tabor A. Oral soy supplementation and dermatology. Cosmetic Derm. 2007; 20:202-204.
9. Blair RM, Tabor A. The beauty of soy for skin, hair, and nails. In: Nutritional Cosmetics: Beauty from Within, Tabor A, Blair RM (eds). William Andrew Applied Science Publishers/Elsevier, 2009, pp 441-468.