The sun is one of the main things that makes life possible on this planet. Unfortunately, it can also be very harmful to human beings. Many cultures across the world enjoy being in the sun, but that regular sunbathing habit or even long walks for some Vitamin D in the morning sun can have deleterious effects on your health.
Sunlight contains ultraviolet radiation (UV radiation), which is a form of electromagnetic radiation that comes from the sun and man-made sources like tanning beds and welding torches. It is not as harmful as other forms of radiation like x-rays and gamma rays, but it is not completely harmless either.
This is the reason you should always wear sunscreen when you are exposed to sunlight, even for short durations. Unfortunately, most people are either using too little sunscreen, or not using it at all. In this article, we shall learn a little more about UV radiation, and how you can protect yourself from it.
What are the types of UV radiation?
It is important to know the different types of UV radiation because each have different levels of energy and as a result cause varying levels of damage to the skin and the cells’ DNA.
There are three main groups of UV radiation:
- UVA rays: These have the least energy and can accelerate aging of the skin cells while also causing some indirect damage to cells’ DNA. They are mainly linked to long-term damage like wrinkles, age spots, and scaly patches, but are suspected to cause some skin cancers.
- UVB rays: These have more energy than UVA rays and directly damage the cells’ DNA. They are responsible for sunburns and most skin cancers.
- UVC rays: These have the highest energy levels. Luckily, because of this, they react with ozone high in the atmosphere and do not reach the ground, so they do not affect us heavily.
What is sunscreen?
Sunscreen is a topical product applied to the skin to protect it from the harmful effects of the sun. There are two main types of sunscreens available on the market:
- Mineral sunscreens: These contain zinc dioxide and/or titanium dioxide and sit on the surface of the skin. The mineral nanoparticles bounce UV rays off the surface of the skin, preventing them from causing damage to the skin. They are effective against both UVA and UVB rays.
- Chemical sunscreens: These contain chemicals like avobenzone and octisalate are absorbed into the deeper layers of your skin. They absorb UV rays and convert them into harmless heat, which they then release from the skin. They are effective against UVB rays but may not provide optimal protection against all UVA rays.
When do I need sunscreen?
Many people assume that on cloudy days, or days when you remain indoors, you do not need sunscreen. This is untrue. UV rays can penetrate clouds, and they can also pass through glass to enter your house. It is therefore important to wear sunscreen during daytime, especially between 10am and 4pm, when UV radiation is at its highest.
Darker skinned people also need sunscreen to protect their skin, even with the added protection of their melanin. Although skin cancers are more prevalent among white people, they still occur among darker skinned people, and you must take the necessary precautions to protect yourself.
What should I consider when selecting a sunscreen?
The most important factor to consider when choosing a sunscreen is the level of SPF (sun protection factor) it provides.
The SPF number tells you how long the sun’s UVB rays would take to give you sunburn if you apply the sunscreen exactly as directed compared with the amount of time it would take without sunburn. So, with an SPF 15 product, it would take you 15 times longer to burn than if you used no sunscreen.
The American Academy of Dermatology Association recommends that you use a product of SPF 30 or higher. It should be water resistant or sweat-proof for at least 40 minutes, and it should be broad spectrum, meaning it protects you from both UVA and UVB rays. The amount of sunscreen required to cover all exposed areas of the body is one ounce, which is about the volume of a shot glass.
The higher the SPF number, the higher the protection afforded by the sunscreen. You can also gauge how high the SPF you require is by looking at the daily UV index for the place you are in. For UV indexes ranging from 1 to 5, an SPF 30 product is sufficient. However, for higher UV indexes, it would be wise to look at higher SPF products.
Innocent Immaculate Acan is a medical doctor and writer. She won the Writivism Short Story Prize in 2016 and has published an illustrated children’s book titled The Pearl Trotters in Black, Yellow, Red. She was part of the 2018 class of the Young and Emerging Leaders Project.