The skin is the largest external organ of your body and is thus the most prone to environmental damage. While pollution and seasonal changes do have major effects on your skin, they are nothing compared to the serious and long-term damage UV exposure can have. Whether you are an outdoorsy person or not, UV exposure can get to you anywhere (indoors as well!) and cause damage. It is known that even a 15-minute exposure to direct sun can affect your skin negatively. The types of UV rays effect on skin is varied and we got our resident skin expert Dr. Sravya Tirpineni to shed some light on the same…

 

3 Types of UV exposure affect the skin

3 types of UV exposure affect the skin

Ultraviolet radiation Is an electromagnetic form of energy and comes from sunlight, as well as lasers and black lights. The sun is the most significant source of UV radiation that a normal human being is subjected to. The radiation is generated as a result of a nuclear reaction at the sun's core and it travels to the earth via the sun rays. Here are the major types of UV rays and the effects they have on your skin…

 

The types of UV radiation at a glance

The types of UV radiation at a glance

The sunlight contains ultraviolet radiation and it consists of a varying spectrum of rays. The UV radiation that affects the skin does so in different manners. The classification of UV radiation is done based on the wavelength of the rays. UVA has the longest wavelength, UVB has a medium wavelength and UVC the shortest wavelength.

The longest wavelength has the lowest energy, which means UVA affects your skin cells only in the top layer of the skin. The inner cells are also distressed to an extent, causing immediate tanning, sunburn, etc. UVB, on the other hand, causes delayed tanning, excessive sunburn and blistering. These effects vary in different wavelengths, with UVA and UVB being of prime concern.

UVC rays are completely absorbed by the atmosphere and are rarely a cause of concern for you. However, you can be exposed to UVC radiation through UVC sanitising lights, arc-welding torches, and mercury lamps.

 

UVA and UVB rays in detail

UVA and UVB rays in detail

As mentioned above, UVA and UVB rays are the major cause of concern for skin, so let’s take a look at them in detail -

1. UVA rays

  • UVA rays comprises 95% of the radiation reaching the earth
  • They have higher wavelengths and they have lower energy levels than other UV radiation. But they are more penetrating than the UVB rays which means they can affect deeper layers of the skin and cause indirect damage to the DNA.
  • They cause the skin to age earlier or prematurely and this is seen in the form of wrinkles. These are also associated with some skin cancers.
  • Unlike UVB rays, they are not absorbed by the ozone layer, hence about 95% of this radiation reaches the earth. This causes immediate tanning and sometimes sunburn if you're out too long​.

2. UVB rays

  • UVB rays consist of only 5% of radiation because they are filtered by the ozone layer.
  • They have shorter wavelengths and higher energy levels so they damage the outermost layers of the skin and directly damage DNA.
  • UVB rays cause most skin cancers, but can also cause wrinkling as well. Overexposure to UVB rays will cause us to get a sunburn and usually the delayed effects or delayed tanning also appears.
  • The UVB rays do not penetrate windows and are more likely to be filtered by the clouds.

 

Short term and long term effects of UV exposure

3. Short term and long term effects of UV exposure

1. UVA rays

It has the lowest energy level and only the inner cells in the top layer of the skin including the dermis are affected. The short-term effects include immediate tanning and sunburn. The long-term effects include premature ageing, wrinkles and certain skin cancers.

2. UVB rays

UVB has a higher energy level as compared to UVA rays and affects cells in the top layer of the skin. The short-term effects are delayed tanning, sunburn and blistering. The long-term effects of skin cancer can also contribute to premature ageing.

3. UVC rays

UVC is the lesser-known wavelength and can affect outermost cells in the top layer of the skin. The short-term effects include redness, ulcers and severe burns. In the long term, it can cause skin cancer and premature ageing, but is not so commonly seen as the sources are not commonly encountered.

 

How to protect yourself from UV radiation

4. How to protect yourself from UV radiation

One of the best ways to protect your skin from UV damage is to use sunscreen, here are some things you need to remember -
Some of the expert-recommended tips to protect your skin from UV radiation and keep it healthy are -

  1. Always choose a sunscreen that offers broad-spectrum protection, this means it protects from both UVA and UVB rays.
  2. No sunscreen is 100% effective in protecting you from UV rays, but anything with an SPF of 30 or higher will be appropriate.
  3. If you are participating in activities like swimming or any kind of water sports, water-resistant or waterproof sunscreens should be used. It is imperative that the sunscreen is applied every 2 to 3 hours, especially if you are sweating, exercising or swimming.
  4. Physical sunscreens that contain oxide and titanium dioxide, are a safe and effective pick. You can also use a mineral-based sunscreen (chemical) which has more of a cosmetic appeal and lighter texture to the skin.

Also, stay in the shade between 10 AM to 4 PM because this is when the UV rays are strongest. Wear a hat or carry an umbrella and wear sunglasses whenever possible. Try to get your vitamin D fix from food and supplements instead of from the sun in order to protect your skin from harmful UV rays.

 

UV rays facts you need to know

UV rays facts you need to know

Here are some UV rays facts that you need to keep in mind -

  1. UV radiation is the highest in the spring and in the summer months, because during this season the sun is at a higher angle; hence increasing UV intensity. However, it can still affect you during fall and winter.
  2. UV exposure is highest in areas that are on or near the equator - India being a tropical country, thus has more UV radiation because the UV rays have less distance to travel before reaching the ground.
  3. UV rays are more powerful at higher elevations because of lesser distance of travel.
  4. The ozone layer depletion has increased UV exposure intensity over the past couple of years, making climate change and greenhouse gases the reason for increased interest in protecting oneself from UV exposure.
  5. Clouds filter out some UV rays from reaching the ground, but it depends on the type of clouds. Dark water-filled clouds are the only ones that can block UV rays significantly.

 

FAQs about UV rays

FAQs about UV rays

Q. Can UVA rays affect my skin while indoors?

A. Yes, the effects of the UVA rays appear right away even while indoors. They are able to penetrate windows and clouds and can affect your skin on cloudy days even while indoors, and even in air-conditioned cars.

Q. Can clothes protect you from UV exposure?

A. Regular clothes may not be effective in being safe from UV exposure, but these tightly woven dry fabrics are being made by many outdoor companies for increased protection from UV rays. They are called Sun Protection Factor clothing, and can be opted for staying safe in the sun.

Q. What time of day are UV rays the most damaging?

A. The time of the day when UV exposure is the highest is between 10 AM and 4 PM. During this window of time, the sun rays have less distance to cover and hence are more powerful. This is why it is recommended to avoid long durations of direct sun exposure during this time.