The basis of sunscreens are UV filters of various origins. They can be both physical (inorganic) and chemical (organic). They work in different ways: inorganic filters - titanium dioxide, zinc oxide - reflect UV radiation. Organic filters - octokrelen and avobenzon - absorb UV rays and convert solar energy into heat. Regardless of nature, UV filters must provide stable protection and not be destroyed by exposure to radiation.
Otherwise, even with a high SPF (sun 8rotection factor; sun protection factor) indicated on the package, there is a risk of sunburn.
The composition of the sunscreen affects the way the product is applied to the skin and how it protects. Which, in turn, affects the desire of the buyer to use this product again. If you take two products with the same degree of protection, but with a different nature of UV filters, they will differ in ease of application to the skin. Cream based on inorganic filters is more difficult to distribute.
Such filters are most often used in natural cosmetics.
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You should pay attention to which filter is used in the product. Sunscreens should not contain zinc oxide (nano) - it irritates the respiratory system. The use of filters such as benzophenone-3 and avobenzone is questionable and requires any sunscreen on the packaging.
Ultraviolet radiation is part of the electromagnetic spectrum of solar radiation. UV rays of spectrum C, with a wavelength of 100-280 nanometers (nm), are absorbed by atmospheric ozone. The main part of the UV rays of spectrum A (wavelength - 315-400 nm) and approximately 10% of the UV rays of spectrum B (wavelength 3 280-315 nm) reach the Earth's surface. UV rays of spectrum A and spectrum B are important for human health.
Small doses of UV rays are vital for the production of vitamin D in the human body. However, their excessive exposure can lead to acute and chronic consequences for healthy skin, eyes and the immune system. UV-A radiation is one of the main causes of photoaging and skin cancer. Even for daily care, you should choose products with SPF. According to European requirements, UV-A protection should be at least 1/3 SPF.
Only if this rule is observed, the UVA badge will be placed on the packaging of the product.
Any creams with any SPF work only for two hours. And in order to find out how much sunlight the cream holds back (this is what SPF implies), you need to divide 100% by the SPF index - 10, 15, 30, 50, 60. For example, 100 is divided by 50 and we get the number 2. That is so much percent ultraviolet radiation reaches the skin, and the remaining 98% cream blocks.
Therefore, dermatologists recommend using agents with an SPF of at least 30.
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