Beauty comes from the inside. Skin aging consists of two independents, clinically and biologically, distinct processes such asthe first is intrinsic skin aging, which represents chronological aging and affects skin in the same pattern it affects all internal organs and thesecond is extrinsic skin aging, which is caused by the result of external factors and environmental influence, mainly chronic sun exposure and ultraviolet (UV) irradiation but also smoking, pollution, sleep deprivation and poor nutrition.
Prevention is the best and most effective way to work against extrinsic skin aging effects. The best prevention strategy against the harmful action of free radicals is a well-regulated lifestyle like caloric restriction, body care and physical exercise for bodywith low stress conditions and a balanced nutritional diet containing anti-oxidative rich food.
Antioxidants such as carotenoids, tocopherols and flavonoids, as well as vitamins A, C, D and E, essential omega-3-fatty acids, some proteins and lactobacilli have been referred as agents capable of promoting skin health and beauty.
L-ascorbic acid (vitamin C)
Vitamin C, also named L-ascorbic acid, is water soluble, photosensitive and is the most important antioxidant in the hydrophilic phase. Available in fresh fruits and vegetables such as citrus fruits, blackcurrant, rose hip, guava, chili pepper or parsley.
L-ascorbic acid can be used orally and topically for skin benefits. Vitamin C is a cofactor for lysyl and prolyl hydroxylase, which stabilizes the triple helical structure of collagen and alsoaids in cholesterol synthesis, iron absorption and increases the bioavailability of selenium.
Tocopherols (vitamin E)
The vitamin E complex is a group of 8 compounds called tocopherols.
Higher amounts of tocopherol are available in vegetables, vegetable oils like wheat germ oil, sunflower oil, safflower oil and seeds, corn, soy and some sorts of meat. The intake of natural vitamin E products helps against collagen cross linking and lipid peroxidation, which are both linked to aging of the skin.
D-α-tocopherol is involved in stabilizing the cell membrane by inhibiting oxidation of polyunsaturated fatty acids, such as arachidonic acid of membrane phospholipids. Topical applied vitamin E is described to reduce erythema, sunburned cells, chronic UVB-induced skin damage and photo carcinogenesis.
Carotenoids (vitamin A, β-carotene, astaxanthin, retinol)
Carotenoids are vitamin A derivates like β-carotene, astaxanthin, lycopene and retinol, which are all highly effective antioxidants which possess photoprotective properties.
Carrots, pumpkin, sweet potatoes, mangos and papaya are some examples of β-carotene containing fruits and vegetables.
β-carotene can be further enriched in skin, in which it is already a major carotenoid. β-carotene is an endogenous photoprotector, and its efficacy to prevent UV-induced erythema formation.
Astaxanthin is found in microalgae, yeast, salmon, trout, krill, shrimp, crayfish and crustacea. Astaxanthin is biosynthesized by microalgae or phytoplankton, which are consumed by zooplankton or crustacea. They accumulate astaxanthin and, in turn are ingested by fish which then accrue astaxanthin in the food chain.
Lycopene is a bright red carotene and carotenoid pigment and phytochemical found in tomatoes and other red fruits and vegetables, such as red carrots, watermelons and papayas.
β-carotene and lycopene are usually the dominating carotenoids in human blood and tissues and are known to modulate skin properties when ingested as supplements or as dietary products. While they cannot be compared with sunscreen, there is evidence that they protect the skin against sunburn (solar erythema) by increasing the basal defence against UV light-mediated damage.
Retinol is important for the human body; however, the body itself cannot synthesize it. Retinol, a fat-soluble unsaturated isoprenoid like its two important metabolites retinaldehyde and retinoic acid, is essential for growth, differentiation and maintenance of epithelial tissues. In human skin two retinoid receptors are expressed, which can be activated by retinol and its metabolites.
Retinol must derive from diet. Natural retinol and retinol ester are contained in liver, milk, egg yolk, cheese and fatty fish etc. Naturally occurring and synthetic vitamin A show similar biological activities. Different retinol products, both for cosmeticand pharmaceuticaluse can be found on the market.
Flavonoids
Phlorizin belongs to the group of dihydrochalcones and its a type of flavonoids which is naturally occurring in some plants. It could be found in the bark of pear (Pyrus communis), apple, cherry and other fruit trees. Its anti-aging effects are removeswrinkles, roughness, solar spots changes in pigmentation and protect from UV.
Essential Fatty Acids (Vitamin F)
Essential fatty acids (EFAs) are long-chain polyunsaturated fatty acids derived from linolenic, linoleic and oleic acids. They cannot be produced in the human body and they have to be consumed through our daily dietary intake. EFAs have also been known as vitamin F. Arachidonic acid is a semi-EFA, as it can be synthesized in the body from linoleic acid. The two families of EFAs are ω-3, derived from linolenic acid, and ω-6, derived from linoleic acid. They are present in fish, shellfish, flaxseed, hemp oil, soya oil, canola oil, chia seeds, pumpkin seeds, sunflower seeds, leafy vegetables, walnuts, sesame seeds, avocados, salmon and albacore tuna. EFAs are essential for the synthesis of tissue lipids, play an important role in the regulation of cholesterol levels and are precursors of prostaglandins.
Skin-aging appearance was defined as having a wrinkled appearance, senile dryness, and skin atrophy. Higher linoleic acid intakes were associated with a lower likelihood of senile dryness and skin atrophy.
EFAs can also be found as artificial supplements in the market. Fish oil supplements are usually made from mackerel, herring, tuna, halibut, salmon, cod liver, whale blubber, or seal blubber, are rich in omega-3 fatty acids and often contain small amounts of vitamin E. They might be also combined with calcium, iron, or vitamins A, B1, B2, B3, C or D.
By : Anjalee Lunuwilage
Editorial board – SSS 2019