What is The Difference Between UVA and UVB Rays?
6 min read
OCT 31, 2022 - by FELIP GERDES
What is The Difference Between UVA and UVB Rays?
6 min read
OCT 31, 2022 - by FELIP GERDES
When our skin burns, we are quick to direct our blame towards our exposure to the sun's visible light. However, the real culprit is actually invisible in the form of UV radiation. Like visible light, UV radiation is a spectrum of frequencies that can be split into distinct bands such as UVA and UVB. What is the difference between UVA and UVB? Each affects the skin differently, and thus requires different protection in order to keep skin healthy and prevent premature aging
When our skin burns, we are quick to direct our blame towards our exposure to the sun's visible light. However, the real culprit is actually invisible in the form of UV radiation. Like visible light, UV radiation is a spectrum of frequencies that can be split into distinct bands such as UVA and UVB. What is the difference between UVA and UVB? Each affects the skin differently, and thus requires different protection in order to keep skin healthy and prevent premature aging
01
UV radiation
Before we differentiate between UVA and UVB rays, it's essential to grasp the concept of UV radiation itself and understand what UV light does to skin. Ultraviolet (UV) radiation is a form of electromagnetic radiation emitted by the sun that causes ionization. When skin cells are exposed to ionization, they experience damage, which weakens the overall health of skin. 1 UV radiation is typically categorized into three types: UVA, UVB, and UVC. UVC rays are almost entirely absorbed by the Earth's atmosphere and do not reach the surface, leaving us primarily concerned with UVA and UVB light. 2
01
UV radiation
Before we differentiate between UVA and UVB rays, it's essential to grasp the concept of UV radiation itself and understand what UV light does to skin. Ultraviolet (UV) radiation is a form of electromagnetic radiation emitted by the sun that causes ionization. When skin cells are exposed to ionization, they experience damage, which weakens the overall health of skin. 1 UV radiation is typically categorized into three types: UVA, UVB, and UVC. UVC rays are almost entirely absorbed by the Earth's atmosphere and do not reach the surface, leaving us primarily concerned with UVA and UVB light. 2
What is UVA?
UVA rays make up the majority of the UV radiation that reaches the Earth's surface. Because of their longer wavelengths and lower energy, they are able to penetrate the atmosphere much easier than other types of UV rays. 3 This means that they are relatively constant throughout the year, even on cloudy days. These properties also allow UVA rays to penetrate the skin more deeply than UVB rays, affecting the collagen structure of the
dermis, the skin's middle layer. 3
What is UVA?
UVA rays make up the majority of the UV radiation that reaches the Earth's surface. Because of their longer wavelengths and lower energy, they are able to penetrate the atmosphere much easier than other types of UV rays. 3 This means that they are relatively constant throughout the year, even on cloudy days. These properties also allow UVA rays to penetrate the skin more deeply than UVB rays, affecting the collagen structure of the
dermis, the skin's middle layer. 3
What is the impact of UVA rays?
UVA rays are notorious for their ability to accelerate the skin's aging process. UVA rays penetrate into the dermis, creating reactive oxygen species (ROSs), which directly damage collagen fibers. 4 They also
induce senescence, increasing the number of senescent cells in the skin. Senescent cells secrete a number of harmful biochemicals, including matrix metalloproteinases (MMPs) which also degrade collagen proteins. This damage leads to sagging skin, fine lines, and wrinkles. Even though UVA rays are less likely to cause immediate sunburn, their long-term effects on the skin's health should not be underestimated.What is the impact of UVA rays?
UVA rays are notorious for their ability to accelerate the skin's aging process. UVA rays penetrate into the dermis, creating reactive oxygen species (ROSs), which directly damage collagen fibers. 4 They also
induce senescence, increasing the number of senescent cells in the skin. Senescent cells secrete a number of harmful biochemicals, including matrix metalloproteinases (MMPs) which also degrade collagen proteins. This damage leads to sagging skin, fine lines, and wrinkles. Even though UVA rays are less likely to cause immediate sunburn, their long-term effects on the skin's health should not be underestimated.What is UVB?
On the other hand, UVB rays are short-wavelength, higher energy ultraviolet B rays; their intensity varies daily, seasonally, and geographically. UVB rays can bounce off or be absorbed by the atmosphere. With shorter wavelengths, UVB rays can’t reach quite as far into the skin as UVA rays and therefore primarily affect the epidermis
, the skin's outermost layer. UVB rays are the main culprits behind sunburns and play a significant role in the development of skin cancer. 4
What is UVB?
On the other hand, UVB rays are short-wavelength, higher energy ultraviolet B rays; their intensity varies daily, seasonally, and geographically. UVB rays can bounce off or be absorbed by the atmosphere. With shorter wavelengths, UVB rays can’t reach quite as far into the skin as UVA rays and therefore primarily affect the epidermis
, the skin's outermost layer. UVB rays are the main culprits behind sunburns and play a significant role in the development of skin cancer. 4
What is the impact of UVB rays?
The two types of sunscreens are based on their active ingUVB rays, with their shorter wavelength and higher intensity, have a more immediate and visible impact on the skin. These rays penetrate the epidermis, causing damage to DNA within skin cells and triggering an immune response. This increases blood flow to the affected areas, which causes redness, pain, and inflammation, known as sunburn. 5 Prolonged or repeated UVB exposure over time can lead to more severe outcomes, such as the development of skin cancer.
edients, and include chemical sunscreens and physical (or mineral) sunscreens. Chemical sunscreens work by absorbing high energy UV rays and emitting them at low energy levels as heat. Mineral face sunscreens work by forming a physical barrier that blocks UV rays from penetrating skin cells. What is the impact of UVB rays?
The two types of sunscreens are based on their active ingUVB rays, with their shorter wavelength and higher intensity, have a more immediate and visible impact on the skin. These rays penetrate the epidermis, causing damage to DNA within skin cells and triggering an immune response. This increases blood flow to the affected areas, which causes redness, pain, and inflammation, known as sunburn. 5 Prolonged or repeated UVB exposure over time can lead to more severe outcomes, such as the development of skin cancer.
edients, and include chemical sunscreens and physical (or mineral) sunscreens. Chemical sunscreens work by absorbing high energy UV rays and emitting them at low energy levels as heat. Mineral face sunscreens work by forming a physical barrier that blocks UV rays from penetrating skin cells. When are UV rays strongest?
The strength of UV rays varies depending on several factors, including geographic location, time of day, and season. UVB rays are typically strongest between 10 a.m. and 4 p.m. during the spring and summer months. This is because during the winter months, UVB rays are angled and thus more likely to be absorbed or reflected by the atmosphere. 6 However, UVA rays are able to penetrate the atmosphere much easier resulting in relatively consistent intensity throughout the day and year, making them a year-round concern.
When are UV rays strongest?
The strength of UV rays varies depending on several factors, including geographic location, time of day, and season. UVB rays are typically strongest between 10 a.m. and 4 p.m. during the spring and summer months. This is because during the winter months, UVB rays are angled and thus more likely to be absorbed or reflected by the atmosphere. 6 However, UVA rays are able to penetrate the atmosphere much easier resulting in relatively consistent intensity throughout the day and year, making them a year-round concern.
02
Protecting your skin from UVA and UVB rays
Because of the significant damage that UVA light and UVB light can cause, broad spectrum protection of your skin is an important step in any skincare routine year round. Here are three steps you can take to protect your skin from the sun.
02
Protecting your skin from UVA and UVB rays
Because of the significant damage that UVA light and UVB light can cause, broad spectrum protection of your skin is an important step in any skincare routine year round. Here are three steps you can take to protect your skin from the sun.
Keep your skin healthy
Healthy skin is resilient skin, making it better equipped to repair itself when damaged by UV radiation. Keeping skin healthy and resilient takes a lot of resources and the right topical skin care products
. The skin requires nutrients like vitamins A, C, and E, as well as omega-3 fatty acids. These nutrients cannot be synthesized by the body and must be consumed through foods like fish, meat, dairy, fruit, and legumes.7Additionally, it’s important to stay well-hydrated, get enough sleep, and
manage stress, as these factors can also impact your skin's resilience.Keep your skin healthy
Healthy skin is resilient skin, making it better equipped to repair itself when damaged by UV radiation. Keeping skin healthy and resilient takes a lot of resources and the right topical skin care products
. The skin requires nutrients like vitamins A, C, and E, as well as omega-3 fatty acids. These nutrients cannot be synthesized by the body and must be consumed through foods like fish, meat, dairy, fruit, and legumes.7Additionally, it’s important to stay well-hydrated, get enough sleep, and
manage stress, as these factors can also impact your skin's resilience.Avoid UV exposure
Extreme UV exposure can cause long term damage to the internal structures of cells and increase the risk of developing skin cancer. Limit your time in direct sunlight, especially during peak hours between 10am and 4pm. Seek shade when possible, and wear protective clothing like long-sleeved shirts and wide-brimmed hats whenever possible in order to avoid burns from UVB rays. Remember that UVA rays can penetrate clouds and windows so it's important to take protective measures and wear sunscreen during winter
and even on cloudy days. 6
Avoid UV exposure
Extreme UV exposure can cause long term damage to the internal structures of cells and increase the risk of developing skin cancer. Limit your time in direct sunlight, especially during peak hours between 10am and 4pm. Seek shade when possible, and wear protective clothing like long-sleeved shirts and wide-brimmed hats whenever possible in order to avoid burns from UVB rays. Remember that UVA rays can penetrate clouds and windows so it's important to take protective measures and wear sunscreen during winter
and even on cloudy days. 6
Wear Broad Spectrum Sunscreen
Broad spectrum sunscreen is the best way to protect your skin from both UVA rays and UVB rays, and it is also incredibly easy to incorporate into a daily skin care routine. Apply sunscreen generously to exposed areas and re-apply as necessary. Not all sunscreens are created equal. OneSkin’s OS-01 SHIELD provides broad-spectrum SPF 30+ PA+++ protection with ingredients such as zinc oxide and the OS-01 peptide. OS-01 SHIELD not only protects skin from advanced UV aging with 100% Non-nano Mineral
Broad Spectrum UV filters and potent antioxidants, it is scientifically proven to reduce the effects of UV-induced aging! 8
To uphold your skin's health and maintain its optimal hydration, it's essential to incorporate a peptide face moisturizer and a peptide body moisturizer into your daily skin care regimen, complementing the protection provided by sunscreen. These products, working in harmony, not only shield your skin from harmful UV radiation but also ensure that your skin remains well-nourished, resilient, and hydrated, safeguarding your long-term skin health.Wear Broad Spectrum Sunscreen
Broad spectrum sunscreen is the best way to protect your skin from both UVA rays and UVB rays, and it is also incredibly easy to incorporate into a daily skin care routine. Apply sunscreen generously to exposed areas and re-apply as necessary. Not all sunscreens are created equal. OneSkin’s OS-01 SHIELD provides broad-spectrum SPF 30+ PA+++ protection with ingredients such as zinc oxide and the OS-01 peptide. OS-01 SHIELD not only protects skin from advanced UV aging with 100% Non-nano Mineral
Broad Spectrum UV filters and potent antioxidants, it is scientifically proven to reduce the effects of UV-induced aging! 8
To uphold your skin's health and maintain its optimal hydration, it's essential to incorporate a peptide face moisturizer and a peptide body moisturizer into your daily skin care regimen, complementing the protection provided by sunscreen. These products, working in harmony, not only shield your skin from harmful UV radiation but also ensure that your skin remains well-nourished, resilient, and hydrated, safeguarding your long-term skin health.Key Takeaways:
- UV radiation, emitted by the sun, causes damage to skin cells. It's divided into UVA, UVB, and UVC rays, with UVA and UVB being the most relevant for human skin.
- UVA rays have longer wavelengths and penetrate the skin more deeply, affecting the collagen structure in the dermis. They are responsible for skin aging.
- UVB rays are short-wavelength and primarily affect the skin's outermost layer, the epidermis. They are responsible for causing sunburn and play a significant role in the development of skin cancers.
- Protecting your skin from both UVA and UVB rays is crucial. This can be achieved by maintaining overall skin health, avoiding excessive UV exposure, and using broad-spectrum sunscreen with ingredients like zinc oxide and antioxidants.
Key Takeaways:
- UV radiation, emitted by the sun, causes damage to skin cells. It's divided into UVA, UVB, and UVC rays, with UVA and UVB being the most relevant for human skin.
- UVA rays have longer wavelengths and penetrate the skin more deeply, affecting the collagen structure in the dermis. They are responsible for skin aging.
- UVB rays are short-wavelength and primarily affect the skin's outermost layer, the epidermis. They are responsible for causing sunburn and play a significant role in the development of skin cancers.
- Protecting your skin from both UVA and UVB rays is crucial. This can be achieved by maintaining overall skin health, avoiding excessive UV exposure, and using broad-spectrum sunscreen with ingredients like zinc oxide and antioxidants.
By Felip Gerdes: Felip is an aspiring lawyer studying political science at the UC San Diego. For more on Felip, check out his LinkedIn.
By Felip Gerdes: Felip is an aspiring lawyer studying political science at the UC San Diego. For more on Felip, check out his LinkedIn.
References
- Zonari, A., et al. Senotherapeutic peptide treatment reduces biological age and senescence burden in human skin models. Npj Aging, 9(1), 1-15. 2023.
References
- Zonari, A., et al. Senotherapeutic peptide treatment reduces biological age and senescence burden in human skin models. Npj Aging, 9(1), 1-15. 2023.
Reviewed by Alessandra Zonari, PhD, Chief Scientific Officer (CSO) and Co-Founder of OneSkin
Alessandra earned her Master’s degree in stem cell biology, and her PhD in skin regeneration and tissue engineering at the Federal University of Minas Gerais in Brazil in collaboration with the 3B’s Research Group in Portugal. Alessandra did a second post-doctoral at the University of Coimbra in Portugal. She is a co-inventor of three patents and has published 20 peer-reviewed papers in scientific journals.
Reviewed by Alessandra Zonari, PhD, Chief Scientific Officer (CSO) and Co-Founder of OneSkin
Alessandra earned her Master’s degree in stem cell biology, and her PhD in skin regeneration and tissue engineering at the Federal University of Minas Gerais in Brazil in collaboration with the 3B’s Research Group in Portugal. Alessandra did a second post-doctoral at the University of Coimbra in Portugal. She is a co-inventor of three patents and has published 20 peer-reviewed papers in scientific journals.