Sunscreen
Choosing the Right Sunscreen: What You Need to Know
Summer is approaching, and everyone dreams of relaxing in the sun. While the sun is beneficial for the body and mind, prolonged exposure can be harmful to the skin. No exposure without protection!
UVB is the main cause of sunburn
No sun, no life. The sun is the source of multiple benefits for the body (providing heat, synthesizing vitamin D through the skin, a sense of physical well-being) and for the mind. It even improves certain skin conditions, such as psoriasis or eczema. But if you overuse it, the consequences can be harmful to the skin.
The ultraviolet radiation (UVA and UVB) emitted by solar radiation can cause irreversible damage to skin cells. UVB represents only 2% of ultraviolet rays, but they are very energetic. They are the main culprits of sunburns, which can range from simple redness with a sensation of warmth to a real burn with painful swelling accompanied by fever, headache. Repeated burns during childhood are risk factors for the occurrence of skin cancer (melanomas, carcinomas) in adulthood.
UVA rays, on the other hand, penetrate the dermis, cause degradation of collagen and elastin fibers, and are the main responsible for accelerated skin aging (wrinkles, dry skin, appearance of brown spots). Sunscreen products should, therefore, prevent visible or invisible, immediate, or long-term effects of UVB and UVA rays. To achieve this, they contain combined mineral filters that reflect UV filters and chemicals that absorb UV. Mineral filters consist of inert powders (zinc oxide, titanium dioxide) and do not cause allergies. Therefore, they are mainly found in sunscreen products intended for sensitive skin and children.
Four categories of sunscreen products
Sunscreen products are classified according to their level of protection (sunburn protection factor or SPF), sun protection index (IP5), or even sun protection factor (SPF), in four categories:
1. Low protection, SPF between 6 and 14;
2. Medium protection, SPF between 15 and 29;
3. High protection, SPF between 30 and 59;
4. Very high protection, SPF of 60.
SPF does not guarantee a duration of protection: applying a sunscreen with a high index does not mean that sun exposure can be longer. It does not provide any information on UVA protection. That's why brands add UVA protection, but there is no single index. As for the term "total protection," it should no longer be used.
How is the protection index calculated?
The calculation of the protection index results from a method that all laboratories apply. Volunteers expose their backs, divided into different areas (one without sunscreen, the other or the others covered with sunscreen) to artificial UV radiation. This determines the dose of radiation needed to cause the equivalent of a sunburn (minimum erythema dose or MED). The protection index is the ratio between the MED on the skin protected by the product and the MED on the unprotected skin. Regardless of the brand, the SPF corresponds to the same level of protection. Note, however, during laboratory tests, 2 mg of sunscreen are used per square centimeter, which is never done in practice, as it would be equivalent to using a quarter tube of cream in a single application.
My skin type
Each of us has a unique ability to sunbathe and develop sunburn. This ability is determined by hereditary factors, such as skin or hair color, which is called phototype. Scientists generally classify skins into six categories. In practice, four main phototypes are distinguished:
1. Redheads with milky white skin, extremely sensitive to the sun;
2. Blondes with fair skin, sun-sensitive;
3. People with intermediate skin, brown hair with sufficiently thick light skin, renewing quite easily, getting sunburned during very intense exposures;
4. People with fairly sun-resistant skin, brown hair, brown skin with easy tanning.
Which product to choose?
The choice of protection coefficient should essentially depend on the skin's phototype and the intensity of the sun. Exposure can be:
• extreme (mountain, tropics);
• important (beach, long outdoor activities, etc.);
• moderate (outdoor life ...).
The lighter the skin color, the higher the exposure, and the higher the index.
Enhanced protection for children
Children spend most of their time outdoors and are not prepared to defend themselves from the sun. Their fragile skin keeps the traces of sunburn for many years, risk factors for the appearance of skin cancer in adulthood. It is estimated that a child receives three times more UVB per year than an adult and that half of a person's sun exposure during life occurs before the age of 18.
If the sun is necessary for health, it represents a danger to children's skin. Before the age of 3, direct sun exposure is prohibited because the skin is immature, thin, and vulnerable. Their thermoregulatory system is insufficient, and we must be very careful about the risks of dehydration and heatstroke. This fragility of children's skin persists until the age of 8-9. Therefore, it is advisable to expose them as little as possible and favor clothing protection. The sunscreen used should be of very high protection and "special for children." Avoid using products with chemical filters on young children.
Avoid the appearance of small blisters on the neckline
After two or three days of exposure, you are covered with small blisters on your arms and neckline. This is undoubtedly Polymorphic light eruption (PLE): it is characterized by the appearance of red nodules accompanied by intense itching, mainly affecting young women.
These small pimples and itching disappear as soon as you stop exposing yourself. PLE is the result of brutal exposure to ultraviolet rays and can reappear every year if you are not careful. To avoid it, take three weeks before exposure and throughout the sun exposure, dietary supplements based on carotenoids (beta-carotene, lycopene) and anti-free radical vitamins (A, C, E) that prepare the skin to tan, strengthening its defenses. Expose yourself very gradually at first, avoiding hours rich in UVB (12 to 4 pm), and use high protection sunscreen products.
Self-tanner, smooth and bronzed skin
The self-tanner causes skin coloration without the intervention of solar radiation. Most often it contains dihydroxyacetone or DHA, which darkens in the air by oxidation. It looks good two or three hours after application. It is then eliminated over the days. The obtained coloration is only superficial. Be careful, the self-tanner does not prevent the appearance of sunburn. It is advisable to exfoliate before application. This way, the coloration is more uniform, and the result is natural. Be sure to rinse your hands well after application.
Tips for the proper use of sunscreen products
- Insist on sensitive areas (ears, neck, nose, shoulders).
- Gradually reduce the index when the tan intensifies.
- Apply sunscreen in a sufficiently thick layer and renew the application every two hours and after bathing, even if the product is presented as water-resistant.
- Avoid prolonged sun exposure, even with a high index cream.
- Close the product well after use and store it in the shade.
- After opening, do not keep sunscreen for more than one season.
Medication + sun, beware of danger
Certain medications increase skin sensitivity and can induce reactions in it. The intensity of the reaction depends on the dose and exposure of the drug. The responsible medications are very numerous: certain antibiotics, anti-inflammatories, antidepressants. If you are taking any medication, before any exposure, consult your pharmacist.
Did you know
At the beach, you are not fully protected under a parasol. This does not prevent sunlight reflected by the sand.
Clouds, wind, and swimming have a deceiving effect, giving you a false sense of coolness and the impression that the sun is not shining.