dr samdhattwrites
move over sunscreens
In the first of a two part series, Dr SamDhatt looks at controlling the damage of ultraviolet rays with antioxidant-rich, pre- and post-sun treatments.
The effects of UV radiation on the skin are well documented, and themainstreammedia has extoled the preventive benefits of sunscreens for years. However, sunscreens don’t block all the earth’s ultraviolet light and they’re way under- utilised.
Fortunately, there are numerous ingredients that canmitigate the sun’s damage when applied prior to exposure and, in some cases, even reverse UV-induced signs of ageing once the damage is done.
the sun’s UV assault
For years, we’ve known that chronic UV exposure results in DNA damage, photoageing, hyperpigmentation and skin cancer. Specifically, UVA exposure generates harmful compounds known as reactive oxygen species (ROS), including singlet oxygen, hydrogen peroxide and hydroxyl free radicals.
These ROS react with the skin’s DNA, proteins, lipids and saccharides, causing oxidative damage that can lead to injured blood vessels, structural damage to the DNA, an impaired immune systemand cell death – or, in plain English, wrinkles, loss of elasticity, age spots and skin cancer.
While reactive oxygen species are wreaking their havoc on the skin’s keratinocytes, the predominant cells comprising the epidermal layer, and fibroblasts, the dermal cells responsible for generating connective tissue, the sun’s UVB rays are depleting the skin of its natural antioxidants, rendering it defenseless against the sun’s UV-induced free
radicals.This leads to a cascade of evenmore damaging events, ultimately resulting in the degradation of yetmore collagen and elastin.
Fortunately, we have antioxidants – the best antidote to the sun’smayhem. In recent years, one specific class of antioxidants known as phenolics have received significant regard among the antioxidant category for their ability to protect the skin before, during and after UV exposure.
treating the skin with phenolics
Formulators often integrate vitamins C, E and beta-carotene into pre- and post- treatment skin care to help fortify the skin’s defenses against UV-induced free radicals.
But Phenolics, representing one of the richest sources of the plant-based antioxidant family, may be capable of protecting the skin at even greater levels and in different ways against the sun’s assault. Indeed, many phenolic flavonoids such as Quercetin, Luteolin and Catechins offer more effective antioxidants than what vitamins C and E and Beta-carotene can offer single-handedly1
.
With approximately 8,000 naturally occurring compounds to their name, Phenolics encompass phenolic acids, flavonoids and polyphenols and are naturally abundant in fruit, namely Berries, Citrus, Grapes,Apples,Apricots, Cherries and Plums, and vegetables, such as Onions, Broccoli, Tomatoes, Lettuce, Olives, Cabbage and Eggplant. Coffee beans, Tea, grains and even red wine also offer plentiful sources of Phenolic acids, Flavonoids and Polyphenols.
Phenolics, particularly polyphenols, exhibit health benefits ranging from antiviral, antibacterial, immune- stimulating, anti-inflammatory and anti- carcinogenic activity. Even after the skin has absorbed its fair share of reactive oxygen species, the Flavonoids and Phenolic acids of these ingredients are hard at work, scavenging the free radicals, chelating metal ions such as iron and copper, and inhibiting the activities of damaging enzymes in the skin.
Resveratrol One of the most well-known phenolic ingredients, Resveratrol rose to fame in 2004 when its cancer-fighting and heart- protective benefits were lauded widely by the mainstream press. Today, skin care chemists continue to turn to this potent antioxidant for its free radical-scavenging and anti-inflammatory benefits.
Breen&BlackTea Polyphenols Another widely used antioxidant and anti- inflammatory source, Green and Black Tea (Camelia sinensis) offer one of the best, most proven natural defenses against the sun’s harmful UV rays. Tea provides Polyphenols such as Epigallocatechin-3- gallate (EGCG).Many published studies have proven tea’s anti-inflammatory and anti-carcinogenic abilities at even multiple stages of cancer formation in mice4
.
Green Tea Polyphenols, in particular, have been shown to protect the skin against UVB-induced edema (swelling) and erythema (redness), lipid peroxidation (the ‘stealing’ of electrons which leads to free radical production), depletion of enzymes essential to the skin’s antioxidant defense system and more5
.
In a report published in Free Radical Biology &Medicine, researchers demonstrated Green and Black Tea’s ability to scavenge the ROS hydrogen peroxide and inhibit UV-induced DNA damage. Green Tea Polyphenols also have the ability to induce apoptosis (cell death) in human cancer cells5, 6
.
Ferulic&CaffeicAcids Grains, fruits and vegetables not only provide a great source of vitaminsA, C, E and B, they also yield Ferulic and Caffeic Acids, both of which have demonstrated the ability to protect the skin’s
Sourced from the skin and seeds of Grapes, Peanuts and Berries, Resveratrol has proven itself as a significant inhibitor of UVB-induced skin edema when topically applied to mice. In fact, pre- treatment of Resveratrol resulted in a decrease of UVB-induced Hydrogen Peroxide and Leukocytes, a marker of UV- induced oxidative stress, according to a study published in Frontiers in Bioscience2
.
Most recently, a 2011 European Journal of Pharmacology study demonstrated Resveratrol’s ability to increase the viability of human keratinocytes following UVA exposure and protect them from UVA stress while up-regulating antioxidant enzyme activity3
.
GUILD NEWS 117
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