Did you know these harmful effects of UV rays on your skin?

Sunlight contains ultraviolet radiation, which consists of many types of rays. The types of Ultraviolet radiation you are probably most familiar with must be UVA and UVB rays. Such rays can affect your skin in many ways.

In the article below, we’ll take a much closer look at the key differences between UVA and UVB rays, how they are able to affect your skin, and what you can probably do to limit sun damage.

What is actually this UV radiation?

Ultraviolet radiation is a type of electromagnetic energy which can be obtained from natural sources, like sunlight, as well as from artificial sources, like for instance lasers, black lights, and tanning beds.

Out of which the sun is the most significant source of this UV radiation. It found its root in the nuclear reaction at the core of the sun, and this particular radiation travels to the earth's surface via the sun’s rays.

Basically, these UV rays can be classified according to their wavelength:

UVA (The longest wavelength)
UVB (The Medium wavelength)
UVC (The shortest wavelength)

Effects of UVA rays:

They have a higher wavelength, but lower amount of energy levels than other UV rays.
They are more penetrating than UVB rays, which can affect your skin cells much deeper into the skin.
They are capable of causing indirect damage to your DNA.
They cause your skin to age prematurely, leading to some visible effects such as wrinkled skin. They are in turn capable of causing some kinds of skin cancers.
Unlike, UVB rays, they are not completely absorbed by the ozone layer. About 95% of the UV rays that reach the earth's surface are UVA rays.
They can also cause an immediate effect of tanning, and sometimes even a sunburn. The effects of exposure to these UVA rays tend to appear immediately.
UVA rays are the main light used in tanning beds.
They are easily capable of penetrating windows and clouds.

8 harmful effects of UVB rays:

They are relative to UVA rays, UVB rays tend to possess shorter wavelengths and high amounts of energy levels.
UVB rays tend to damage the outermost layers of your skin.
They can directly damage your DNA.
UVB rays are capable of causing most types of skin cancers, also they can contribute to skin aging problems prematurely.
The ozone layer partially absorbs them, but some rays still manage to get through. About 5% of the entire UV rays that manage to reach the earth's surface are UVB rays.
Overexposure to these UVB rays leads to severe sunburns. Usually, it is found that the effects of these UVB rays are delayed, or visible a few hours after sun exposure.
Most tanning beds use a combination of both of these UVA and UVB rays. Some of the special UVB-only tanning beds may be seen as safe, but they will still cause your skin to get damaged. No tanning beds are called to be a safe option to use or recommended.
They cannot penetrate windows and are much more likely to be filtered by the presence of clouds.

Benefits of UVA and UVB Rays:

Both ‌UVA and UVB rays do have some major health benefits. It is found that ‌UVB rays can help your skin make vitamin D3 which is very important for muscle building and bone health.
UVA and UVB rays are both used in a type of light therapy known as phototherapy. Phototherapy can be helpful in serious cases of:

Rickets: A condition found in children where your bones get softer and quite weaker because of the lack of vitamin D.
‌Psoriasis, eczema: Skin conditions where your skin can turn scaly, red, or itchy.
Vitiligo: A skin condition where patches of the skin lose their color
Phototherapy has also shown various possible benefits for serious pain relief.
Localized scleroderma: Also known as Morphea, it is a rare skin condition that causes your skin to possess thick reddish patches or problematic skin.

5 Steps to protect from UVA and UVB rays

To keep your skin safe and healthy, it’s important to protect yourself from UV rays, especially if you stay outdoors for a long time.

Consider the tips mentioned below to limit sunburn, premature aging, and DNA damage:

Apply sunscreen

Choose a sunscreen that provides broad-spectrum protection as it has the ability to block out both UVA and UVB rays.

A higher SPF will provide more protection. But do remember sunscreen needs to be reapplied at least every 2 hours or more frequently if you’re sweating, swimming, or exercising.

Cover up

Clothes do help protect from UV exposure. Tightly woven dry fabrics are best.

Stay in the shade

Limit your exposure to direct sunlight by keeping yourself in the shade. This is most vital between 10 am and 4 pm when the rays are stronger.

Wear a hat

A wide-brimmed hat can provide some extra protection to your ears and neck.

Wear sunglasses

Wear sunglasses that provide UV protection to prevent damage to your eyes and the surrounding skin.

Takeaway

Both rays can damage your skin. UVA rays can penetrate deeper into your skin and cause your skin cells to age prematurely. Around 95% of the UV rays that reach the ground are UVA rays.

The other 5% are UVB and have higher energy levels than UVA rays. UVB rays typically damage the skin's outermost layers, causing sunburn. They also directly damage DNA and are the reason for most skin cancers. So whenever going out in daylight carry sunscreen which has an SPF of more than 30.

Frequently Asked Questions

1. Does sunscreen expire?

Sunscreens are required to remain at their original strengths for at least three years declared by the food and drug administration which means that you can apply leftover sunscreen from one year to the next. Some sunscreens do have an expiration date — a date indicating when they're no longer effective.

2. Does sunscreen prevent tanning?

The answer is no. It doesn't protect you 100%. Sunscreen acts like a barrier or guard for your skin, but that doesn't mean it's impenetrable. UV rays can still enter your skin and result in a tan, even when you're wearing a lot of sunscreens.

3. How long does sunscreen last?

Most health officials agree that sunscreen should be reapplied every two hours. The reason for this rule comes down to how SPF is tested. SPF ratings are generally based on how much sun protection a sunscreen product will provide you against the sun for 120 minutes.

References

How to choose the best sunscreen? Saturn by GHC, Mar 22, 2022.
What is UV radiation? By American cancer society, Jul 10, 2019.
UVA vs UVB. By National Library of Medicine.

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