The arrival of summer rhymes with sun protection: hat, clothes but also sun creams! These contain screens that protect our skin from the harmful effects of the sun. How do they work? What do the terms UVA, UVB, SPF mean? And besides, how to apply sunscreens to obtain maximum efficiency?
What are the different types ofsunscreens ? There are two types: UV absorbers and UV reflectors. The former have the property of absorbing UV rays and converting them into heat (imperceptible).
- UV absorbers include atoms of carbonthey are organic or chemical.
- The latter disperse UV rays. They consist of oxides (oxide of zinc or oxide of titanium) and are minerals.
Organic filters and mineral filters can be used by the manufacturer in nanometric form. In this case, the mention nano must appear next to the name of the ingredient on the packaging. Sunscreen products may contain one or more sunscreens.
UVA and UVB: what is the difference?
The ultraviolet type A are responsible for skin aging and penetrate deep into the dermis. Type B ultraviolet rays are responsible for Sun burn and are limited to the epidermis. Both types of ultraviolet can cause skin cancer, although UVB seems to play a more important role than UVA. The solar products must protect against UVA and UVB. We are talking about products “to spectrum wide “.
What is the sun protection factor?
The sun creams filter most but not all UV rays. Some still manage to penetrate the skin. The Sun Protection Factor, or SPF, is an indicator of the sunscreen’s ability to protect against the sun’s rays. The higher it is, the better the cream performs.
An SPF 30 means that the product passes 1/30e rays, i.e. 3.3% of UV rays. An SPF 50 means that the product passes 1/50e spokes, i.e. 2%. In other words, a 50 cream provides 98% protection.
How to use a sunscreen product?
For sunscreen to actually protect you from Suna few precautions must be observed:
- The ideal is to apply the sunscreen a few minutes before exposure so that the cream can penetrate the skin well.
- The product should be applied every two hours and after each swim. If you exercise and you sweat, a application even more frequent is needed.
- Care must be taken to apply the product so as not to miss any areas.
- You have to put enough product. For a whole adult body, you need to put 35 ml of product to get the maximum protection.
- Do not use a product that has expired or that has been started for more than 12 months.
As a reminder, do not expose yourself between 12 and 4 p.m. Young children should not be left in direct sunlight. Even with a sunscreen, the time of exposure to the sun must remain reasonable.
Interested in what you just read?
Subscribe to the newsletter Health question of the week : our answer to a question you ask yourself (more or less secretly). All our newsletters