Under the heading Diet: Meat Diet
The choice of sun protection
So, sunscreen cosmetics used chemical, physical filters and their various combinations created to enhance the effect of UV protection.
Chemical filters able to absorb solar radiation due to its chemical structure, and by using modern compounds as UV filters, the absorption of types A and B.
Physical filters reflect and scatter radiation. In the application and the one and the other group sunscreens there are subtleties that determine the price and cosmetic products and their effectiveness.
Sunscreens are developed (scary thought!) Since 1891. The first filter were, of course, mineral filters. Over the past since the time of sunscreen formulations made perfect. Modern facilities - complex multicomponent systems containing not only the combined filters, and various additives that enhance the protective effect.
Today, the most widely used two physical filters - titanium dioxide and zinc oxide. The most important manufacturing techniques in - that the particles of these materials must be strictly defined size, or protective properties may change. For example, an increase in particle size is shown on the skin of "whiting effect" means that there is unevenly distributed in the skin, resulting in sunburn turns "stripes."
More improvements compositions with mineral filters for particles of substances applied special coating to separate them, and did not change the solar control properties. To extend the range of the reflected light, a combination of titanium dioxide and zinc oxide as a first active against UV B, and the second - against ultraviolet A zinc oxide is more transparent. Sometimes, it is rarely used another material - iron oxide. It has a brick color, is therefore used in low concentrations.
Chemical filters very much. But all of them can be divided into several large groups, so to speak, "chemical origin."
1. A cinnamic acid or cinnamates. They are active against ultraviolet B. The best-known and frequently used in the composition of domestic and foreign cosmetics - octocrylene and EMC (ethylhexyl methoxycinnamate). Note that the largest foreign manufacturers prefer to specify consisting of no chemical and trade name sunscreens, for example, Parsol or Nelitopan.
2. The derivatives of salicylic acid or salicylates such as octyl salicylate, avobenzone. Some representatives of this group are active against ultraviolet A light, some - against ultraviolet B.
3. Benzophenones - the most advanced solar filters, as they provide protection against all types of ultraviolet radiation.
The principle of operation of chemical filters other than the physical. They penetrate the skin, their molecules are aligned in a certain way and there occurs absorption of harmful rays.
For the composition of a sunscreen is important as the content of the additional components that provide resistance of the skin free radicals or hinder this process. Antioxidants are added to the means of solar protection: ascorbic acid (vitamin C), tocopherol (vitamin E), coenzyme Q, calendula extract, pine, spruce, fir, larch. These extracts not only contain natural antioxidants composition, but also have an independent light absorption.
What does the SPF?
The degree of protection of the skin with the help of a cosmetic product depends on the size of the protective factor SPF (a number that indicates how many times the weakened sun exposure while using this tool) - the higher it is, the higher the protective ability of the drug.
For the calculation of safe exposure to sunlight is necessary to multiply the number of SPF at the time of exposure to the sun to burn for your skin type.
The labels of sunscreen you can find four groups according to the degree of protection SPF: low (SPF 2-5), medium (SPF 6-11), high (SPF 12-19) and very high (SPF 20 or more).
As a rule, a low degree of protection has now each daily cream, and higher - sunscreen. Sun protection with chemical filter is recommended for people who have no particular problems with the skin. If the baggage a person has dermatological abnormalities, such as a tendency to the formation of age spots, it is recommended to use only natural filters. For children also use sunscreens that shield the skin rather than absorb radiation.
Doctors recommend a daily basis to protect the skin from harmful solar radiation, because it is the active prevention of skin aging. Using creams with protective filters to avoid the unpleasant effects of sunburn. This is especially important for people with fair skin, children and people with their luggage in diseases of the skin.
Tips for using sunscreens for vacationers:
- With strong insolation, especially if you have fair skin, you should wear light natural fabrics, well covering the body. Such clothing will allow the skin to "rest" after an active tanning on the beach;
- On vacation nice hat with a wide brim;
- Sunscreen should be applied 30 minutes before going out, again - after bathing;
- It is not recommended to use any sunscreen for children in the first six months of life. For their protection, better use of natural light clothing;
- Do not forget about sunglasses - UV detrimental effect on the cornea;
- Some drugs can provoke photoallergy, for example, many antibiotki, contraceptives;
- Such surfaces, such as sand and cement reflect ultraviolet light, that is, you will get higher doses;
- Remember that the risk factors for the negative effect of ultraviolet radiation are: white skin, blond hair, a tendency to the formation of freckles, the trend easily burns, skin diseases in the family, a long stay in the sun for the rest of your life, burning up "bubbles" in childhood or adolescence;
- It is best to carry a tool with different protection factor, including water-resistant (especially true for children);
- The life of photoprotective cream - half a year since the start of use. If the cream is changing smell, texture or color, it can not be used;
- With oily skin need to use sunscreens labeled oil-free - without oil;
- Skin on the face is much more delicate, so protection factor creams for the face to be higher than for the body.
Author: Olga Zorina