Nutramedic &Cosmetics
Photoprotective effect of antioxidants on the skin Although the skin naturally contains antioxidants, their amount becomes limited during sun exposure. Protective agents applied to the skin have their limitations in protecting the skin, and dietary supplements can help compensate for these deficiencies.
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he skin is the largest body organ that plays the role of a biological barrier. It participates in the regulation of body temperature, transmits sensations and prevents harmful substances from entering the body. One of its most important protective functions is to protect against the undesirable effect of solar radiation.
The impact of sunlight on the skin
Sunlight is beneficial for the human body, and one of benefits is stimulation of formation of vitamin D in the skin, which is essential for healthy bones and immunity and increases serotonin level that supports a good mood. But excessive sun exposure, both short and long term, can damage the skin. Besides causing burns, premature skin aging, hyperpigmentation and allergic reactions, it can even lead to serious conditions such as skin cancer. Exposing the skin to the Sun’s UV radiation leads to significant oxidative damage resulting in clinical and histopathological changes, thus contributing to its premature aging. Hyperpigmented lesions, also known as “age spots“, are some of the most noticeable skin changes caused by photoaging. The vast majority of skin damage caused by the Sun results from UV rays, namely UVA and UVB rays. The skin naturally contains an antioxidant system against UV-generated reactive oxygen metabolites. However, this antioxidant protection is not always fully effective during Sun exposure. Oral antioxidants can help reduce the harmful effects of UV radiation and strengthen the physiological antioxidant defences of the skin. Various ways of protecting against UV rays include photo protective clothing and applying topical agents that require repeated application due to localized effect. The introduction of useful oral substances is a promising method, providing uniform protection to the whole body. This has led to the development of a market for dietary supplements and products promoted to improve skin health. All these products have in common antioxidant action.
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AUTHOR:
Daria Šurić, M.Pharm., Darmell
Simply explained, antioxidants “fight” against the oxidation process, which over time leads to the destruction of cells. Since oxidative stress is considered to be the main cause of skin aging, nutrients that have antioxidant effects such as carotenoids, flavonoids, plant extracts and omega-3 fatty acids are of interest. Most UV radiation is filtered through the Earth’s atmosphere, and we are exposed mainly to UVA (95%). Primarily, research has focused on the effects of UVB rays, but lately attention has been more shifted to UVA radiation. Its larger wavelengths allow it to penetrate deeper into the skin. Majority of UVB is absorbed in the epidermis, and UVA radiation also affects the dermis, showing carcinogenicity in animal models. UVB rays can also cause burns. Clinical changes observed in photo aging such as rough structure, wrinkles, spotty hyperpigmentation, vasodilation and loss of elasticity are attributed primarily to the influence of UVA. UVA harms the skin by stimulating the formation of reactive forms of oxygen after they are absorbed by riboflavin, porphyrin and hem-containing proteins. Reactive oxygen molecules can damage import-
