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The single outstanding performer, however, has been the skin care segment in terms of total revenue—it generated $60 billion in global sales in 2007 and grew 10% during the past five years. The question is, will this trend follow the macro-trend of an aging demographic or have we seen all the innovation we might expect to see from skin care? Will men’s grooming and baby care overtake skin care’s historical dominance?
What has driven much of the growth in skin care since 2002 has been the consumer demand for well validated and proven natural ingredients—arguably the biggest claim in this category has been that of “anti-aging.” But can anti-aging sustain the skin care segment into the future? What developments will continue to fuel the growth over the next five years?
Virginia Beach, VA-based Dr. David McDaniel, MD, an internationally renowned dermatologist and fellow of the American Academy of Dermatology, insists the skin care industry has improved significantly over the years, especially in terms of the potency of the products offered, the delivery systems, and the quality of the science. But Dr. McDaniel, who specializes in clinical research and investigation into the science of “Appearance Dermatology,” says there are more opportunities for companies to take an evidence-based approach to skin care and address the other big issue of how to manage the expectations of the consumer, while keeping them engaged long enough for the product to demonstrate the desired results.
As a general rule, Dr. McDaniel says eight to 12 weeks of regular use is usually required to demonstrate a visible result. But he concedes, even within his own practice, four weeks seems to be a common duration for product usage, after which the consumer or patient is either converted to a loyal user or dumps the product in favor of the next big thing.
The Challenge of Quick Results
One approach that has shown demonstrably positive effects within the four-week window is a novel kiwi seed oil from New Zealand. This oil is extracted using a supercritical CO2 process and has been shown to possess some impressive qualities either at 1-3% by volume or applied directly to the skin at night.
The kiwi seed oil is predominately (70% +) alpha linolenic acid (ALA), an omega 3 fatty acid. It also contains a significantly high level of gamma-tocotrienol (one of eight specific isomers of vitamin E). The manufacturers claim to provide over 37 mg gamma-tocotrienol per 100 grams of oil and 53 mg per 100 grams for total tocotrienol content. This compares directly to palm oil, which is considered among the world’s richest sources of gamma-tocotrienol; palm oil ranges from 28-43 mg per 100 grams. It is also important to note that kiwi seed oil has significant polyphenolic content and a water-soluble antioxidant capacity (ORAC) in excess of 17,000 uM TE per 100 grams, which is very high for oil.
What is the relevance to skin care of kiwi seed oil having a high ALA concentration, high gamma-tocotrienol and an unexpected water-soluble antioxidant capacity in the oil?
For anti-aging skin care, the significance is only apparent in the context of a recent hypothesis of wrinkle development and accelerated photo-aging in skin. When reviewing this underlying mechanism of action, one must consider the role of UVB in accelerated aging and wrinkle formation.
The Wrinkle Hypothesis
In April 2008, researchers at the Tokyo University of Technology reported that long-term skin aging studies supported their hypothesis for a mechanism of wrinkle formation, whereby inflammatory cytokine expression is activated by UV irradiation. This cytokine expression sets up an inflammatory cascade, which triggers dermal fibroblasts to increase the expression of elastase. The increase in elastase production in turn results in the deterioration of the three-dimensional architecture of elastic fibers, reducing skin elasticity, and finally leading to the formation of wrinkles.
Dr. McDaniel, who has extensively studied the impact of solar radiation and other environmental stress and injury on accelerated aging in skin, agrees with this model and believes it could be further amplified, particularly since UVA/UVB affects the up-regulation of inflammatory cytokines within the cell, as well as inducing a cascade of reactive oxygen species (free radical attack). These processes attack the cellular membrane and other diverse targets within the cell. Dr. McDaniel believes both pathways are significantly responsible for assaulting the tissue, resulting in damage to the micro-architecture of the skin, leading to wrinkle formation and accelerated aging.
While many active ingredients claim to up-regulate collagen and elastin production, until the catabolic processes are switched off through inhibition of ROS (reactive oxygen species) and suppression of inflammatory activity, these pro-collagen effects will have limited benefit.
Alpha Linolenic Acid & Wrinkles
In 2002, Japanese researchers demonstrated that dietary ALA inhibited the erythema score after UVB irradiation. They also demonstrated that UVB-induced prostaglandin E2 (PGE2) production was significantly lower in the group fed an ALA-rich diet compared with the control group. The researchers concluded from their results that the type of fatty acids—n-6 or n-3—is critical for the suppression of UVB-induced skin lesion when the “skin” fatty acids are modified by dietary manipulation. Anti-inflammatory activity of diet with a relatively high ALA and low linoleic acid content was demonstrated in UVB-irradiated hairless mice model.
Tocotrienols & Wrinkles
The significance of tocotrienols in skin care (and in particular gamma-tocotrienol) has come to light during the past few years. Researchers at Sugiyama Jogakuen University in Japan had previously shown that a vitamin E admixture extracted from palm oil could result in specific distribution of vitamin E isomers in an animal model. This research group concluded that when fed as part of the diet, tocotrienols were selectively taken up in the skin. They also claimed the skin to be a unique tissue in its ability to discriminate between various vitamin E analogs.
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The Role of Other Antioxidants
One reason vitamin E has not performed well in earlier studies is that it doesn’t work well in isolation, especially the tocotrienols. As far back as 2000, Lester Packer and colleagues from the University of California, Berkeley, during a presentation at Experimental Biology, noted that tocotrienols are uniformly distributed on the surface of the cellular membrane where they easily collide with ROS and facilitate the recycling activity of the chromanoxyl radical. Dr. Packer reported that vitamin E, as a class of compounds, does not work in isolation from other antioxidants, but instead forms part of an interlinking set of redox reactions with antioxidants such as vitamin C.
What is interesting about kiwi seed oil, with its unique omega 3/vitamin E/water-soluble antioxidant composition, is that the same material that is shown to benefit the skin when taken orally is also shown to be useful when it is applied topically. By industry standards, kiwi seed oil would be considered a “nutricosmetic” since it is efficacious for skin care both as an ingestible and as a topical.
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