Nutritional Supplementation to Combat Skin Aging
Already a well-established strategy for women in Asian and European cultures, targeted oral nutritional supplementation to support skin health and beauty is a more recent introdution within North America. Unlike topical products, which are applied to targeted areas, these nutritional formulations are taken orally then metabolized and distributed throughout the body. Additionally, the bloodstream continuously supplies these bioactive compounds to all skin compartments (i.e. epidermis, dermis, subcutaneous fat). Therefore, by working systemically, nutricosmetics are able to further protect and support the health of the skin (Madhere 2009).
Nutritional Support for General Skin Health
Minerals such as selenium, copper and molybdenum are required cofactors for the maintenance of antioxidant defense systems in the skin.
Recently, certain natural ingredients such as curcumin, resveratrol, Coenzyme Q10, and SOD-enriched melon extract, have been shown to stimulate the production of these primary defense antioxidants (Lima 2011; Macy-Mary 2007; Pillai 2005).
There is some clinical research showing that selenium-dependent glutathione peroxidase enzyme activity is low in participants with acne vulgaris. One study examined the effect of selenium and vitamin E, in which acne patients took 200 mcg of selenium with 10 mg of vitamin E twice per day for 12 weeks. At the end of the trial, a reduced number of lesions and visual skin improvements were observed, especially in participants with low baseline glutathione peroxidase activity (Sarici 2010; Smith 2007).
Carotenoids are a group of fat soluble compounds found in orange and red fruits and vegetables that confer antioxidant protection within the skin (Ross 2011). Lycopene, found predominantly in tomatoes and tomato-based products, is well-supported in the scientific literature for skin photoprotection.When skin is subjected to UV light stress, more skin lycopene is destroyed compared with beta-carotene, suggesting a role of lycopene in photoprotection against UV damage in tissues. In one trial, 20 women ingested 16 mg of lycopene daily for 12 weeks. After being exposed to UV radiation and in comparison to the control group, the lycopene-supplemented group had a significant reduction in post-UV exposure reddening and inflammation. The researchers concluded that lycopene effectively protected the skin from acute and potentially long term photodamage (Rizwan 2011).
In another study, researchers investigated the effect of a tomato-based drink on markers of inflammation, immunity and oxidative stress within the skin. Subjects were given either a drink containing 5.7 mg of lycopene, along with several other tomato-derived antioxidants, or placebo for 26 days. At the end of the trial, inflammatory intermediates were more than 34% lower in the group that consumed the tomato-based drink (Riso 2006).
Trials (in animals and in humans) have shown that Coenzyme Q10 suppresses the UV radiation-induced inflammatory response in skin cells. In an eight year prospective study of 117 patients with melanoma, CoQ10 plasma levels predicted the risk of metastasis. CoQ10 levels were significantly lower in patients than in control subjects and in patients who developed recurring melanoma than those who did not (Rusciani 2006).
Another nutrient of interest for skin health is Vitamin D, which is synthesized in the skin upon exposure to UV-B radiation (Goldfaden, 2010). Insufficient vitamin D levels have been linked in epidemiology studies to decreased physical performance, poor cardiac health, autoimmune disease, neurologic disorders, several cancers, and increased overall mortality (Sage 2010). In its active form as calcitriol, vitamin D contributes to healthy skin cell renewal and repair. It also supports the skin’s immune system and can neutralize free radicals within the epidermal layers. (Goldfaden 2010; Cashman 2008; Sage 2010).
However, with the notable dangers associated with excess sun exposure, vitamin D deficiency is an epidemic in North America and throughout the world (Hagenqu 2009; Cashman 2008). With more frequent sunscreen use (although required), less sun exposure, and natural aging, the skin’s ability to manufacture vitamin D is compromised, emphasizing the need for dietary and supplemental intake (Goldfaden 2010; Sage 2010; Cashman 2008; Hageneau 2009;).
Polyphenols are a large family of naturally occurring compounds that are widely distributed in plant-based foods. Dietary sources of polyphenols include onions (flavonols); cacao beans, grape seeds (proanthocyanidins); tea (catechins), apples and red wine (flavonols and catechins); citrus fruits (flavanones); berries and cherries (anthocyanidins); and soy (isoflavones).
A variety of polyphenols possess substantial skin photoprotective effects (Nicols 2010). Once ingested, this type of antioxidant is rapidly utilized in the body, therefore daily consumption of polyphenols is recommended to provide efficient skin protection.
The role of dietary components, such as, catechins from green tea and proanthocyanidins from grape seeds, have been assessed in prevention of UV-induced skin carcinogenesis in vitro and in vivo in animal models (Katiyar 2011; Singh 2011; Choudhury 2011). A recent trial published in the Journal of Nutrition, found that when women consumed a beverage containing 1,402 mg of catechins daily, skin was better protected against harmful UV radiation; the intervention also improved overall skin quality (elasticity, roughness, hydration,) over 12 weeks (Heinrich 2011).
Fern Extract (Polypodium Leucotomos)
Extracts from the leaves of a certain species of fern, Polypodium leucotomos (PL) have been shown in clinical studies to effectively block ultraviolet (UV)-induced skin phototoxicity (Caccialanza 2011; Gonzalez 2010; Reuter, 2010).
In one study, 53 patients with sun allergy condition (Idiopathic photodermatoses), consumed 480 mg PL extract daily while exposing themselves to sunlight. Over 73% of the patients had a benefit from the administered PL, with significant reduction of skin reaction or irritation and subjective symptoms. With no side effects observed, the study authors concluded that oral supplementation with PL effectively and safely provides photoprotection (Caccialanza, 2011).
Another clinical trial found that oral PL effectively reduced skin reddening induced by artificial UVR. Moreover, upon histological examination of skin biopsies taken from the subjects who consumed PL extract, decreased skin cell DNA damage and immune activation was noted (Middelkamp-Hup 2004). The authors of this study concluded that "oral administration of PL is an effective systemic chemophotoprotective agent leading to significant protection of skin against UV radiation".
PL extract appears to be especially effective in those whose skin is particularly sensitive to the sun. Several studies have found that oral PL blunts dermal allergic responses to sun exposure in those prone to such reactions (Tanew 2011).
A recently published comprehensive review, by Gonzalez et al. (2010), of the mechanisms by which PL combats photoaging sates the following:
"PL is a natural mixture of phytochemicals endowed with powerful antioxidant properties. Its short-term effects include inhibition of reactive oxygen species production induced by UV radiation, DNA damage, isomerization and decomposition of trans-urocanic acid [an endogenous sunscreen-like agent], prevention of UV-mediated apoptosis and necrosis, as well as degradative matrix remodeling, which is the main cause of photoaging. These short-term effects translate into long-term prevention of photoaging and photocarcinogenesis. A striking property is that PL can exert its effect when administered orally. Together, these effects postulate PL as a natural photoprotective agent and a potential adjuvant to phototherapy for various skin diseases."
In addition, a recent animal model elucidated further mechanisms by which PL guards against photodamage (Zattra 2009). This experiment found that PL dramatically reduced the sun-induced expression of COX-2, which drives inflammation and contributes to skin cancer growth, while it simultaneously increased the expression of a major DNA repair protein, P53. In animals fed PL, UVR exposure induced 25% fewer DNA mutations than in animals receiving a control diet.
Natural Ingredients to Restore Skin
Ceramides make up the lipid rich protective layer within the epidermis. Although present in other tissues, their highest concentration is found in the skin. We can obtain ceramides through foods, mainly rice bran, wheat flour, and wheat germ oil. Ceramide concentrations decrease naturally with age and since they play an important role in preventing dehydration in the skin, oral supplemented plant-based ceramides may help to combat breakdown associated with aging (Bak 2011; Jennemann 2011; Cho 2011).
In a randomized trial, 51 women (aged 20-63 years,) with dry skin were given either 350 mg of a non-GMO wheat extract containing ceramides or placebo for 3 months. After evaluating skin hydration in the legs, arms and face at the beginning and end of trial, a significant increase in skin hydration and an improvement in the clinical signs of dryness were observed at the end of 3 months (Guillou 2011). When combined with antioxidants in oral formulations, it has been shown that ceramides further optimize systemic absorption and utilization of water-soluble antioxidants, such as ascorbic acid (vitamin C). (Bak 2011; Jennemann 2011; Cho 2011).
Recent research has confirmed the antioxidant and DNA protective effects of soy isoflavones in skin. It is the protective effect of genistein that is believed to block UV-induced cellular damage (Accorsi-Neto 2009). In addition to the photoprotective benefits, active components of soy have demonstrated other beneficial effects for the skin. For instance, soy protein peptides have favorably stimulated collagen and hyaluronic acid production within the dermis in vitro (Sudel 2005).
Since they exert weak estrogenic activity, soy isoflavones may assist in delaying accelerated skin aging due to hormonal decline in post-menopausal women (Accorsi-Neto 2007; Izumi 2007). For example, to assess the effect of soy isoflavones on skin aging, 30 post-menopausal women were administered 100 mg/day of isoflavone-rich soy extract for 6 months. At the end of the study, researchers observed that over 86% of the women experienced significant increases in skin thickness, collagen and elastin fibers, and microcapillary density (Accorsi-Neto 2009). In another trial, skin benefits were observed when 40 mg soy isoflavones were taken daily for 12 weeks (Izumi 2007).
Topical Interventions in Skin Aging
Since their introduction in the 1980’s, "cosmeceuticals" (a topical product that exerts both cosmetic and therapeutic benefits), have continued to evolve to ward off the signs of skin aging (Bruce 2008). Sunscreens are the most important cosmeceutical, and retinoids have proven their safety and effectiveness in reducing photo-damaged skin and are now a mainstream treatment for skin anti-aging (Darlenski, 2010). However, emerging categories of cosmeceuticals are proving effective in maintaining vibrant skin.
Generally, there are four categories of cosmeceuticals on the market. These include, exfoliating and whitening agents, antioxidants and regenerating products, such as peptides and stem cell-based skincare (Amer 2009; Benson 2007; Berson 2008).
The use of alpha hydroxy acids (AHAs) has been shown to improve skin texture and reduce the signs of aging by promoting cell shedding in the outer layers of the epidermis and by restoring hydration. They are used often to improve skin texture and for treating mild to moderate photo-damage (Antoniou 2011; Bruce 2008).
The most common ingredients used in formulations and peels include;
- Citric Acid
- Glycolic Acid
- Lactic Acid
- Malic Acid
- Pyruvic Acid
- Tartaric Acid
Cutting-Edge Topical Ingredients
Peptide-based creams represent a breakthrough in skincare technology.
Within the skin, collagen deterioration results in the formation of protein fragments, called peptides. These fragments are then recognized by collagen-producing cells, which respond by increasing collagen production in order to repair the damaged skin. However, with advancing age, this positive feedback between skin breakdown and the initiation of new collagen formation becomes inefficient.
Researchers have discovered that application of these protein fragments directly to the skin circumvents the natural deterioration in collagen turnover. Therefore, by applying specialized peptides to your skin, you can effectively "trick" collagen-producing cells into ramping-up collagen production (Benson, 2007; Namjoshi 2010).
One such peptide is palmitoyl tetrapeptide-3. This synthetic amino-peptide complex effectively stimulates collagen synthesis by interacting with receptors that turn on genes responsible for cell proliferation and renewal. This patented pentapeptide significantly enhances the production of collagen and elastin within the extracellular matrix of the skin. This increased production complements the volumizing action of hyaluronic acid, thereby resulting in visibly reduced wrinkle depth, density, and number. Studies show that this patented ingredient is as effective as the vitamin A derivative retinol in reducing the signs of photoaging, yet it does not cause the skin irritation associated with retinol (Stein 2002).
Argireline (acetyl hexapeptide-3) is a relatively new topical anti-wrinkle ingredient that reduces pre-existing wrinkle depth through a novel mechanism. This active peptide works by significantly down-regulating muscle contraction, interfering with the neurotransmitters that make your muscles contract, thereby preventing the formation of unwanted lines and wrinkles. This natural ingredient appears to be especially beneficial for visibly reducing wrinkle depth around the eyes and forehead (Benson 2007; Blanes 2002; Ruiz 2010).
The breakdown of skin scaffolding is a major cause of wrinkles.
A compound known as Matrixyl® synthe’6™ has been found to complete the maturation and stabilization of fibers, thereby stimulating the scaffolding of skin molecules.
In a controlled clinical study, 25 women aged 42-70 were assigned to one of two groups. Cream was applied 2 times daily (Sederma 2011). One group applied a placebo cream, while the other group applied a 2% solution of Matrixyl® synthe’6™. Scientists later measured the participants’ wrinkles and crow’s feet.
The researchers found that frown lines among the Matrixyl® synthe’6™ group were lifted by 28%, and the volume of wrinkles was diminished by 31%. And this anti-wrinkling effect was observed in just 2 months.
Also, scientists observed that, in the test group, crow’s feet were lifted by 12.6%, and their volume was reduced 21.1%.
Matrixyl® synthe’6™ actively promotes the synthesis of six skin matrix constituents—collagen I, III, and IV, hyaluronic acid, fibronectin and laminin. These skin matrix constituents are found in the lower epidermis, where cells communicate with each other and with the cells in the dermal layer.
Excessive dryness of the skin promotes fine lines and weakens cells. It can cause lipids in the skin’s fatty layer to crystallize, causing dull and flaking skin.
Hyaluronic acid, a natural skin constituent, is a good moisturizer owing to its ability to capture water molecules, which reduces the visibility of lines. It is also a volumizing agent. For these reasons, hyaluronic acid is an ingredient in several skincare applications (Pavicic 2011).
However, scientists have now developed a potent new generation of this compound—an aqueous gel of cross-linked hyaluronic acid, called Hylasome® EG10. This gel forms a thin film on the skin and continuously delivers the larger amount of water bound by this new compound.
When Rutgers University scientists tested this unique gel on human skin, they found that skin cells treated with Hylasome® EG10 held 6 times more moisture in total, and 5 times more moisture in the stratum corneum (extreme outer) layer, than cells treated with hyaluronic acid. This greater moisturizing effect was observed even 24 hours after application (Hylasome® EG10 Monograph)!
Hylasome® EG10 also exhibited an ability to combat oxidation and free radical attack, which can damage skin structure and cause wrinkles.
Vegetal Filling Spheres
Deterioration of skin matrix, combined with moisture loss, results in indentations and wrinkles. But a new compound attacks this problem from deep inside the indentations.
Vegetal filling spheres are derived from wheat protein, which is a biopolymer known for its hydrating capacities.
Scientists applied either vegetal filling spheres, or placebo, to the crow’s feet of 30 volunteers. They observed a 31% decrease in the total wrinkle surface, and a 27% decrease in wrinkle length. And this effect was seen in just one hour! (Product monograph: Vegetal Filling Spheres 2005)
Researchers found the spheres had settled inside the wrinkle indentations deep within the lower epidermis. There, they acted like microscopic sponges, trapping moisture that would normally be lost through the skin surface.
The observed result was a physicochemical effect: the spheres expanded with moisture and physically plumped wrinkles—transforming the skin surface from wrinkled to smooth.
Remarkably, the plumping effect occurs immediately after application—and is long-lasting! There is also a durable increase in hydration of the middle and upper layers of the epidermis.
Skin cell proliferation and collagen synthesis both slow down as we age, producing visible lines.
However, inorganic phosphates, found in almost all cells, were found to inhibit this deterioration. Called Poly P, these phosphates promote tissue remodeling (Kasuyama 2012).
Poly P communicates with skin cells at the dermal layer where fibroblasts—responsible for cell renewal—are produced. Scientists believe this interaction increases production of skin cells, which surface to replace old cells. Also, Poly P is believed to increase the production of collagen.
Boosting production of both collagen and dermal cells improves skin volume and tone, making Poly P a key compound in any modern skincare product.
Studies have confirmed the efficacy of topical formulations containing multiple bioactives, such as a combination of stem cell growth factors, peptides and antioxidant based formulations to combat skin damage and aging.
In a 3 month trial, 37 females with mild to severe signs of photodamage were treated with a facial serum containing naturally occurring stem cell growth factors, peptides and antioxidants, applied twice daily. As early as month one significant visual reductions in wrinkles and improvements in skin texture and radiance were noted; progress continued into months two and three (Atkin 2010).
Natural and Complementary Topical Therapies
Due to the increasing demand for natural ingredients in topical skin care products, antioxidants are being increasingly used in anti-aging skincare. Targeting similar cellular mechanisms as nutritional approaches, topical antioxidants are effective in warding off damaging free radicals and reducing inflammation within the epidermal layers.
Among the most commonly used, ascorbic acid (Vitamin C,) tocopherols (Vitamin E,) alpha lipoic acid and coenzyme Q10. Emerging natural antioxidants proving effective include EGCG (from green tea,) resveratrol, Centella asiatica (Gotu Kola,) proanthocyanidins (grapeseed,) curcumin, pomegranate, silymarin/silibinin (milk thistle,) coffeeberry, melatonin, and marine-based ingredients (Graf 2010; Kerscher 2011; Kohen 2009).
When applied topically, antioxidants have been shown to provide powerful anti-inflammatory, photoprotective and anti-aging skin benefits (Camouse 2009; Graf 2010; Haftek 2008; Kerscher 2011; Kohen 2009; Oresajo 2008, 2010; Puizina-Ivic 2010; Yuan 2011).
In one trial, two different antioxidants were used to stimulate collagen production and improve chronically sun damaged skin. Over 6 months, a cream consisting of 5% Vitamin C and 0.1% madecassoside (Centella asiatica) was applied daily to 20 females with photodamaged skin. At the end of trial, a significant improvement in wrinkles, firmness, roughness and skin hydration was observed (Haftek 2008).
In another trial, researchers assessed the effects of an antioxidant rich cream on the aging face in over 30 women (mean age of 54 years). For 12 weeks, the women were treated with a 5% alpha lipoic acid (ALA) cream (twice daily) or placebo cream. In addition to visible skin improvements, the researchers used laser profilometry to measure skin variables and found there was a 50% average reduction in skin roughness in the ALA-treated skin over the placebo-treated skin. Reseachers concluded the ALA antioxidant cream was effective in improving clinical characteristics of aging and photo-damaged skin (Beitner 2003).
Another ingredient used for its powerful skin anti-aging properties is hyaluronic acid, a sugar-like molecule found in the tissues throughout the body. Originally recognized for its antioxidant effects and wound healing properties (Trabucchi, 2002), hyaluronic acid is used in topical formulations and non-permanent dermal fillers to combat skin aging (Smith, 2008). Within the skin hyaluronic acid is an important component of the structural foundation in the dermis. Its primary function is to attract and bind to water to moisturize and give skin cells volume, while visually smoothing the appearance of skin (Smith, 2008; Tuttle, 2007).
Keratinocytes produce keratin, the material comprising fibrous proteins responsible for strengthening skin membranes. So loss of hydration in keratinocytes causes a weakening of skin cells, resulting in a sagging, wrinkling effect. Also, a depletion of cellular moisture causes lines to be more visible.
Scientists tested hydrating capability of a dried extract of apple fruit, called Botanimoist® AMS (apple moisturizing saccharide) in a placebo-controlled human study. A single topical application of this extract resulted in an 88.9% increase in skin hydration—after just 30 minutes! (Botanigenics).
Even after 6 hours, skin hydration of participants treated with Botanimoist® AMS remained 30.6% higher than the hydration level of untreated skin.
Skin often suffers from insufficient hydration, oxidative stress, or slow collagen turnover. These factors cause weakened cellular structure and result in wrinkles. Also, inflammation of the skin promotes aging.
Resveratrol has long been known as an antioxidant and anti-inflammatory, as well as a mimetic of some of the benefits of calorie restriction. It appears to work partly by activating the sirtuin 1 gene and enhancing the functioning of mitochondria, cellular energy factories (Lagouge 2006).
The application of resveratrol to the skin is linked to anti-aging and anti-inflammatory effects.9And when one study showed that topical application of resveratrol prevented skin cancer in mice treated with a carcinogen, this further suggested a role for resveratrol as a topical skincare agent (Jang 1997).
Scientists then investigated ways to utilize resveratrol to generate a more direct and potent effect on skin appearance. They developed a special resveratrol, which is fermented by pichia pastoris yeast, and tested it on the skin of humans (Metabiotics 2009).
In a double-blind, placebo-controlled, 22-person study, participants applied pichia resveratrol to one side of their faces twice a day. Skin hydration was measured by a special technique known as corneometric reading, and high-resolution photos were taken.
The resveratrol-treated sides of the volunteers’ faces showed a 36% greater degree of hydration over the control sides. Wrinkles were dramatically lifted, and expression lines were noticeably smoothed. These effects were observed after just 28 days! (Metabiotics 2009)