The most common questions in dermatological practice are which sunscreen to use and while going out in the sun what are the sun protection measures to be followed. The answers are here in this article.
Ultraviolet radiation like UVA and UVB have been well documented to have multiple effects on human skin. Ultraviolet radiation causes not only skin cancer but also cutaneous aging like seborrheic keratosis, photomelanosis (pigmentation on sun-exposed parts), wrinkles, polymorphous light eruption, melasma, freckles, lentigines, and urticaria or hives.
Sun protection factor is also called SPF and is measured in the laboratory with a light source, and it is a theoretical amount of time you can stay in the sun without getting sunburns. For example, an SPF of 30 would allow you to stay in the sun 30 times longer than you could without protection. SPF is the degree of protection from ultraviolet B and does not provide protection against ultraviolet A.
Sunscreen agents are classified as either chemical sunscreen, which absorbs light, and physical sunscreen, which reflects, scatters and absorbs light.
Physical sunscreens like zinc oxide (ZnO) and titanium dioxide are always better than chemical sunscreens.
On comparing zinc oxide and titanium dioxide physical sunscreens, zinc oxide is superior in terms of UVA protection and is less pasty.
Avobenzone is the only available chemical sunscreen agent that offers protection against the long-wave UVA, which is mainly responsible for cutaneous cancer, polymorphic light eruptions, and cutaneous lupus erythematosus.
So, before buying sunscreen, you must check the availability of these agents in sunscreen, which give you a broader range of sun protection.
They contain substances like zinc oxide or can be available in combination with titanium dioxide.
It provides a protective seal over the skin's surface, reflecting and protecting the skin from UV light.
They tend to leave the skin with a white tinge.
It is made with minerals.
It is generally thicker and is hard to blend, so it is not preferred for everyday use.
After applying this sunscreen, there is no need to wait for 15 to 30 minutes because it starts to work instantly.
Physical sunscreens are preferred for people with sensitive skin (rosacea).
They contain organic and carbon-based compounds, which absorb UV light and prevent them from penetrating the skin.
They are absorbed fully into the skin but may cause irritation in people with sensitive skin.
It is made with UV filters.
It is generally lighter and non-sticky, so it can be used on the skin daily.
It takes at least 30 minutes to work, so apply the chemical sunscreens before 30 minutes of stepping out.
Chemical sunscreens are preferred for people with oily skin.
When you are going to the pool or beach in the summer, wearing water-resistant sunscreen is important because it helps the sunscreen to stay even when you are wet. But water-resistant sunscreens are a pretty smart option for daily use as well because the rule of thumb is that people should reapply sunscreen every two hours. And many of them do not realize that they are sweating more with their sunscreen throughout the day, especially when it is humid, so in such cases, water-resistant sunscreens give people extra protection even when they are not in actual water. Read the labels carefully whether it contains water resistance or not before buying. Also, sunscreen labels that say to be water-resistant must indicate how long the product can be worn while swimming or sweating in order to reapply it.
Broad-spectrum is the sunscreen that protects against both UVA and UVB. According to the FDA, UVA causes wrinkles, and UVB rays cause sunburn and skin cancer. Most people tend to think about sunburns when it comes to sun protection. But the truth is, they do not know the different types of sun damage it causes. Ultraviolet A rays enter the deeper surface of the skin and may cause signs of aging. These ultraviolet A rays are present throughout the year; even when it is cloudy or sunny, they can enter the windows with the same intensity.
Photo exposed areas need certain protective measures from direct sunlight. They are as follows:
Avoid the midday sun, especially from 10 AM to 4 PM. Seek shade whenever possible.
Wear tightly woven cotton clothing with long sleeves and long pants whenever going out in the sun. Also, wear broad-brimmed hats.
Protect your eyes with UV-filtered sunglasses.
Beware of high altitude places as there are fewer atmospheres to absorb UV rays.
Be cautious at river beds, beaches, and snow places, as 80% of UV rays are reflected.
Then apply plenty of sunscreen to sun-exposed areas in a concentration of 2 mg/cm square.
To apply sunscreen, follow the teaspoon rule:
3 ml, that is, slightly more than half a teaspoon, is applied for each arm and for the face and neck.
6 ml, that is, slightly more than a teaspoon, is applied for each leg, chest, and back.
The sunscreens protect the skin from damage by ultraviolet rays, provided they are applied literally 30 minutes to 1 hour before exposure. It should be reapplied after excessive sweating or swimming or during prolonged ultraviolet exposure. An SPF of at least 30 should be used by fair-skinned individuals and reapplied every 4 to 6 hours as there are no such sunscreens that are completely waterproof. So, reapplication is important.
Daily use of sunscreen is more protective than intermittent use. Sunscreen should be applied even on cloudy days.
Always look into the label while selecting a sunscreen, and check for words like ‘broad spectrum,’ which means the sunscreen can protect the skin from both UVA rays and UVB rays. Also, sunscreen with an SPF of 30 or higher should be preferred. The word ‘water-resistant’ on the label indicates that sunscreen can stay on wet or sweaty skin before it needs to be reapplied. Not all sunscreens offer water resistance, and water resistance lasts for 40 to 80 minutes. So, it is mandatory to look at the label for these words before buying sunscreens.
Last reviewed at:
08 Sep 2021 - 4 min read
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