What Are The Effects Of UV Rays On Skin

What Are The Effects Of UV Rays On Skin


The effects of ultraviolet rays are a cause of growing concern among people these days. UV rays are more energy than visible light. This means that even if we cannot see the rays, our skin is still able to feel them. UV exposure holds the power to harm us without us even realizing it.  

With a rise in the global temperature and ozone layer depletion, worrying about the increased ultraviolet radiation that we may be receiving is not unusual. It is quite normal to think about the effect this may have on our long-term health and how we can fight it. There are many types of UV rays, varying with respect to their effects and characteristics. Being aware of these differences helps us get a clearer idea of the nature of sunlight and these rays.

What Are UV Rays

Ultraviolet (UV) rays are a form of electromagnetic energy. There is a spectrum of electromagnetic (EM) radiation, ranging in frequencies from high-energy radiation (like X-rays, gamma rays) to low-energy radiation (like radio waves). UV rays fall near the middle of this spectrum, having more energy than visibility. 

UV rays are emitted by a wide range of sources, from natural ones, like the sun, to man-made sources like tanning beds and mercury vapour lights. The sun is the major source of UV radiation which results from certain nuclear reactions happening at its core. There are three types of UV rays, classified according to the difference in their wavelength and consequent effects. These are:

  • Ultraviolet A (UVA) Rays
  • Ultraviolet B (UVB) Rays
  • Ultraviolet C (UVC) Rays

Why Are UV Rays Harmful

UV rays differ based on the amount of energy they possess. Rays with higher energy levels hold the capacity to ionize an atom or a molecule by removing electrons from them. This property of the rays damages the DNA in cells, permanently altering it, and eventually leads to cancer. The skin is most affected by the power of the UV rays because they aren’t strong enough to penetrate deeper into the body. 

The level of epidermal melanin in people also plays a role in the level of radiation they can be exposed to without damage. Eumelanin, present in the epidermal layer of the skin, determines the complexion and UV sensitivity of the skin. People with a lighter skin complexion are more UV-sensitive, which increases their risk of developing skin cancer. UV rays have been found to cause a lot of health issues. 

  • Skin Damage

UV exposure damages the skin, causing a variety of skin problems such as premature aging of the skin, wrinkles, leathery skin, and actinic keratosis. Sunburns, liver spots, and solar elastosis are some signs of sun damage on the skin. UV damage accumulates and increases the risk of skin cancer with time. While our body can repair some of the sun damage, the unrepaired cells build up and trigger mutations, causing them to multiply exponentially and turn into tumours.UV is also attributed to the causation of the three most common types of skin cancers- basal cell carcinoma, squamous cell carcinoma, and malignant melanoma. The degree of sun damage is decided by factors such as duration of sun exposure, location, as well as the intensity of the UV rays. The easiest and most efficient way to prevent sun damage is by using sunscreens and other such measures.

  • Eye Problems

Exposure to UV rays is attributed to causing eye damage and problems like cataracts, corneal sunburns, retinal tissue damage, and much more. Cataracts are changes in the structure of the crystalline lens in the eye, leading to blurred vision and blindness. Wearing sunglasses and hats is recommended to lower the eye’s exposure to ultraviolet rays.

  • Weakened Immune System 

Our skin is our body’s first line of defence in our natural immune system. Research suggests that UV rays damage our immune system by suppressing our body’s immune functioning and therefore, the body’s ability to fight some diseases, like skin cancer. UV overexposure may also weaken the effect of immunisations given through the skin, rendering vaccines to be less effective. UV radiation can also lead to the worsening of some medical conditions. 

The strength and exposure of UV rays vary geographically according to the sunlight in that particular area. Owing to atmospheric variations, UV rays are the strongest near the equator, at higher altitudes, and areas with only partial or light cloud cover. Personal habits and lifestyles also affect the UV exposure of a person. Spending a lot of time outdoors without UV-blocking clothes or sunscreen can increase personal UV dosing. Tanning beds are one of the strongest sources of UV exposure. Indoor tanning machines are extremely harmful and poorly regulated, varying widely with respect to the strength and composition of UV rays. They are ten times more powerful than sunlight and have been described as positively carcinogenic.

Ultraviolet rays vary in composition, and each type of ray has some characteristics unique to it.

How Do UV A Rays Affect Our Skin

UVA rays have the least amount of energy as compared to UVB and UVC rays. Although they are weaker than UVB rays, they penetrate deeper into the skin and indirectly damage the DNA of the cells in the innermost part of the skin’s top layer. The skin darkens to protect itself from this damage, leading to the formation of a ‘tan’. Over time this damage may take the form of wrinkles, premature aging, and even skin cancer. Tanning is not safe or healthy at all, and most tanning beds use mainly UVA rays, in addition to UVB rays sometimes. Some tanning beds using only UVB rays are advertised as safe but research has found out the opposite. Unlike its counterparts, UVA rays are not absorbed by the atmosphere and account for 95 per cent of the total UV rays that reach the ground. They can even penetrate windows and cloud cover and are present year-round. Earlier, sunscreens only protected the skin against UVB rays but after looking into the effects of UVA rays, sunscreens now provide protection from both types of UV rays.

How Do UV B Rays Affect Our Skin

UVB rays have more energy and a shorter wavelength than UVA rays. They directly damage the DNA of skin cells in the outermost layer of the skin. They are the main culprits for causing skin cancer and are also responsible for suntans, sunburns, and even blisters. Only five per cent of UVB rays reach the ground, the rest are absorbed by the ozone layer. The intensity of these rays varies according to the sun’s rays and geographic location. UVB rays are generally the strongest from 10 am to 2 pm, although they can be filtered and do not penetrate glass, such as windows. Research has shown that artificial lamps emitting UVB and UVA radiation along with chemical drugs are very useful in the treatment of many skin diseases like psoriasis and vitiligo. Even though such therapy is beneficial, it may include some side effects.

How Do UV C Rays Affect Our Skin

UVC rays have the highest energy levels among the other UV rays. This also means that they react with the ozone in the ozone layer and do not reach the ground at all. Although there are some artificial sources of these rays, such as mercury vapour lamps, UV sanitizing bulbs, and arc welding torches. As the wavelength of UVC rays is also very small, they do not penetrate the skin at all. This eliminates the risk for skin cancer, but UVC exposure, even for a very short time, may cause severe damage to the skin and eyes. They can cause burns, lesions, and ulcers. Direct exposure to UVC rays and looking directly at a UVC light should be avoided at all costs. This is so because even if the injuries are usually healed within a week the effects can be extremely painful. Even a contact of seconds to minutes is enough to cause skin burns and eye injuries from UVC exposure

Are There Any Benefits Of UV Rays

Our body produces vitamin D when exposed to UV rays in the sunlight. Vitamin D has many health benefits, it may even help to lower the risk for certain cancers. The amount of vitamins produced varies from person to person, and many factors such as age, location, and skin complexion. Doctors suggest getting vitamin D from sources other than sunlight and tanning beds, like by following a healthy diet, rich in Vitamin D. Vitamin D supplements may also be a good alternative.

How To Protect Our Skin From UV Rays

Due to global warming in recent years, more UV rays are reaching the ground because of thinning of the ozone layer. This makes it essential for us to limit our exposure to the rays. We cannot stop going outside in the sun, nor is that recommended. Instead, we can change our habits and lifestyle to minimize the damage that the sun can cause to our skin and health.

  • Wearing wide hats that cover your face, ears, and neck from the sun protects the skin.
  • Wearing UV-blocking sunglasses to protect your eyes and face. 
  • Wearing clothes that protect your arms and legs from sun damage is a good idea.
  • Staying in the shade as much as possible when you go outdoors can also help limit direct UV exposure.
  • Choose an appropriate sunscreen and apply it every 2 hours on uncovered areas for optimal effect.

Choosing a sunscreen: There are so many available options for sunscreens in the market, it is easy to become overwhelmed. It is important to choose a sunscreen that offers broad-spectrum protection, this refers to the ability of the sunscreen to block out both UVA and UVB rays. SPF (Sun Protection Factor) refers to the duration of sun exposure that would take to tan your skin when using the sunscreen as compared to without it. The higher the SPF, the better the protection. Doctors recommend using at least an SPF 30 or higher and opting for a water-resistant option for maximum protection.


While ultraviolet rays may not be very healthy, we cannot completely avoid them. The best we can do is to limit our exposure to sunlight and take appropriate measures to make sure we’re being as kind to our skin as we can. Using the right kind of sunscreen can go a long way in our journey to skin protection and care. Being responsible for our daily habits can help us ensure that the effects of UV exposure do not hazardously affect us in the long run.

- 5 Sources

  • Biocule has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references. You can learn more about how we ensure our content is accurate and current by reading our editorial policy.
  • Exposure to UV rays is linked to a number of harmful health conditions (Effects of UV Exposure | Stanford Health Care)
  • When it comes to skin cancer, a major risk factor is prolonged exposure to ultraviolet (UV) radiation (UV Radiation - The Skin Cancer Foundation )
  • Ultraviolet (UV) radiation comes from the sun and man-made sources like tanning beds. Learn more about UV and how to reduce your risk of skin cancer here. (cancer.org)
  • Overview of ultraviolet radiation types and classification. (fda.gov)
  • Both UVA and UVB rays can damage your skin, just in different ways. One causes premature ageing, the other is more prone to causing sunburn, DNA damage, and skin cancer. (healthline.com)
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