Free shipping on orders over $79.00 USD

BLOG

How to Protect Your Skin from UVA and UVB Rays

How to Protect Your Skin from UVA and UVB Rays
Your skin care ritual likely includes an SPF for your face, especially if you’re going to be outside. But did you know certain UV rays can affect your skin indoors? That’s why you need a broad-spectrum sunscreen on your face and body β€” one that protects against UVA and UVB rays. While wearing the right sunscreen is important, it’s just one of the ways you can protect your skin from the sun’s damaging rays, as you’ll learn here shortly. But before we dive in, let’s briefly talk about the difference between UVA and UVB rays.
Your skin care ritual likely includes an SPF for your face, especially if you’re going to be outside. But did you know certain UV rays can affect your skin indoors? That’s why you need a broad-spectrum sunscreen on your face and body β€” one that protects against UVA and UVB rays. While wearing the right sunscreen is important, it’s just one of the ways you can protect your skin from the sun’s damaging rays, as you’ll learn here shortly. But before we dive in, let’s briefly talk about the difference between UVA and UVB rays.
01

What are UVA and UVB Rays?

UVA rays are the ones you don’t see. In fact, 80% of your annual UV exposure is from scattered or indirect radiation from these invisible rays. (1) Not only can they penetrate the atmosphere much easier than other types of rays, they penetrate the skin more deeply too, affecting the collagen structure of the skin’s middle layer, called the dermis, which contributes to premature skin aging. (2) In contrast, UVB rays, which vary throughout the year, don’t reach as deep into the skin’s layers, so they primarily affect the epidermis (or outer layer of skin), resulting in what you experience as a sunburn. With long-term exposure, UVB rays can also lead to the development of skin cancer. (3)
01

What are UVA and UVB Rays?

UVA rays are the ones you don’t see. In fact, 80% of your annual UV exposure is from scattered or indirect radiation from these invisible rays. (1) Not only can they penetrate the atmosphere much easier than other types of rays, they penetrate the skin more deeply too, affecting the collagen structure of the skin’s middle layer, called the dermis, which contributes to premature skin aging. (2) In contrast, UVB rays, which vary throughout the year, don’t reach as deep into the skin’s layers, so they primarily affect the epidermis (or outer layer of skin), resulting in what you experience as a sunburn. With long-term exposure, UVB rays can also lead to the development of skin cancer. (3)
02

Check the Daily UV Index

Ever heard of the UV index? It’s a measure of how intense the sun’s UVA and UVB rays are day to day. Think of it like a sun safety scale for your skin. Ranging from 1 to 11+, this index is an important tool for understanding the potential risks of sun exposure and knowing how to protect your skin. Here's what each range of UV index means:
  • Low (1-2): While UV exposure is minimal, those with very fair skin may still be at risk of sunburn.
  • Moderate (3-5): UV exposure is moderate, and protection is recommended, especially during midday hours when the sun's rays are strongest.
  • High (6-7): UV exposure is high, and protection is essential. It's important to seek shade, wear protective clothing, and use a broad-spectrum mineral sunscreen like new OS-01 BODY SPF (coming soon!) and OS-01 SHIELD for the face.
  • Very High (8-10): UV exposure will be very high, so take extra precautions. Limit outdoor activities, seek shade, and wear protective clothing and sunscreen.
  • Extreme (11+): UV exposure is extreme, and unprotected skin can burn quickly. Avoid outdoor activities during peak sun hours and take all possible precautions to protect your skin.
Checking the UV index can help you take appropriate measures to protect your skin from sun damage. The weather app on your phone can give you real-time information on the UV index.
02

Check the Daily UV Index

Ever heard of the UV index? It’s a measure of how intense the sun’s UVA and UVB rays are day to day. Think of it like a sun safety scale for your skin. Ranging from 1 to 11+, this index is an important tool for understanding the potential risks of sun exposure and knowing how to protect your skin. Here's what each range of UV index means:
  • Low (1-2): While UV exposure is minimal, those with very fair skin may still be at risk of sunburn.
  • Moderate (3-5): UV exposure is moderate, and protection is recommended, especially during midday hours when the sun's rays are strongest.
  • High (6-7): UV exposure is high, and protection is essential. It's important to seek shade, wear protective clothing, and use a broad-spectrum mineral sunscreen like new OS-01 BODY SPF (coming soon!) and OS-01 SHIELD for the face.
  • Very High (8-10): UV exposure will be very high, so take extra precautions. Limit outdoor activities, seek shade, and wear protective clothing and sunscreen.
  • Extreme (11+): UV exposure is extreme, and unprotected skin can burn quickly. Avoid outdoor activities during peak sun hours and take all possible precautions to protect your skin.
Checking the UV index can help you take appropriate measures to protect your skin from sun damage. The weather app on your phone can give you real-time information on the UV index.
03

When (and Where) UV Rays are the Strongest

In addition to the UV index, knowing when UVB rays are at their peak can help you avoid excessive exposure. For example, you’ll want to limit your time in direct sunlight between 10am and 4pm in the spring and summer, seek shade when possible, and wear protective clothing like long-sleeved shirts and wide-brimmed hats.And while it’s true that UV radiation from time spent directly in the sun is the strongest, you can get a surprising amount of UV exposure through cloud cover, windows, clothing, and even while flying. (1). That’s why it’s important to wear a broad-spectrum sunscreen when indoors and on cloudy days.Did you know…
  • Up to 60 percent of UVA rays can penetrate glass, so if you’re anywhere within several feet of a window, the rays can reach you. (4)
  • By law, front windshields are treated to filter out most UVA rays, but side and rear windows generally aren’t. One study found that approximately 74 percent of malignant melanoma appeared on the left side of men, corresponding with sun exposure while driving. (5)
  • If you’re flying, be aware that sun comes through airplane windows as well, and the exposure is often stronger than what you’d get on the ground. (6) Research shows that airline pilots and cabin crew have about twice the risk of melanoma and other skin cancers than the general population. (7) In fact, pilots flying for 56.6 minutes at 30,000 feet are known to receive the same amount of UVA carcinogenic effective radiation as that from a 20-minute tanning bed session. (8)
  • According to the SCF (Skin Cancer Foundation), up to 80 percent of the sun’s UVA rays can pass through clouds, making sunscreen on cloudy days essential. (9)
  • The sun’s rays are stronger at higher elevations too. UV radiation exposure increases about 2-3% with every 1,000 feet above sea level. (10) The threat is even greater in winter, as snow can reflect up to 90 percent of UV rays. (11)
  • Up to 40 percent of UV rays can penetrate shallow water. Sand and water reflect between 25 and 80 percent of UV rays. (12)
  • Wearing a cotton or linen shirt for protection? The average UPF (UV protection factor) of these items is about 5, which means it allows 1/5th of the sun's rays to penetrate your skin. (13)
03

When (and Where) UV Rays are the Strongest

In addition to the UV index, knowing when UVB rays are at their peak can help you avoid excessive exposure. For example, you’ll want to limit your time in direct sunlight between 10am and 4pm in the spring and summer, seek shade when possible, and wear protective clothing like long-sleeved shirts and wide-brimmed hats.And while it’s true that UV radiation from time spent directly in the sun is the strongest, you can get a surprising amount of UV exposure through cloud cover, windows, clothing, and even while flying. (1). That’s why it’s important to wear a broad-spectrum sunscreen when indoors and on cloudy days.Did you know…
  • Up to 60 percent of UVA rays can penetrate glass, so if you’re anywhere within several feet of a window, the rays can reach you. (4)
  • By law, front windshields are treated to filter out most UVA rays, but side and rear windows generally aren’t. One study found that approximately 74 percent of malignant melanoma appeared on the left side of men, corresponding with sun exposure while driving. (5)
  • If you’re flying, be aware that sun comes through airplane windows as well, and the exposure is often stronger than what you’d get on the ground. (6) Research shows that airline pilots and cabin crew have about twice the risk of melanoma and other skin cancers than the general population. (7) In fact, pilots flying for 56.6 minutes at 30,000 feet are known to receive the same amount of UVA carcinogenic effective radiation as that from a 20-minute tanning bed session. (8)
  • According to the SCF (Skin Cancer Foundation), up to 80 percent of the sun’s UVA rays can pass through clouds, making sunscreen on cloudy days essential. (9)
  • The sun’s rays are stronger at higher elevations too. UV radiation exposure increases about 2-3% with every 1,000 feet above sea level. (10) The threat is even greater in winter, as snow can reflect up to 90 percent of UV rays. (11)
  • Up to 40 percent of UV rays can penetrate shallow water. Sand and water reflect between 25 and 80 percent of UV rays. (12)
  • Wearing a cotton or linen shirt for protection? The average UPF (UV protection factor) of these items is about 5, which means it allows 1/5th of the sun's rays to penetrate your skin. (13)
04

For Best Results, Add OneSkin to Your Sun Care Strategy

If you’re not already using a broad spectrum mineral sunscreen that protects against UVA and UVB rays, consider adding OS-01 SHIELD (available in tinted or untinted) or new OS-01 BODY SPF to your routine. Powered by our OS-01 Senescence Blocking Peptide β„’ and formulated with potent antioxidants and 100% non-nano zinc oxide, both have the target cellular aging while protecting from UV damage and leaving skin smooth and glowing. Consider it a trifecta of protection for nourished, healthy skin.
04

For Best Results, Add OneSkin to Your Sun Care Strategy

If you’re not already using a broad spectrum mineral sunscreen that protects against UVA and UVB rays, consider adding OS-01 SHIELD (available in tinted or untinted) or new OS-01 BODY SPF to your routine. Powered by our OS-01 Senescence Blocking Peptide β„’ and formulated with potent antioxidants and 100% non-nano zinc oxide, both have the target cellular aging while protecting from UV damage and leaving skin smooth and glowing. Consider it a trifecta of protection for nourished, healthy skin.
Key Takeaways:
  • UVA rays are invisible and penetrate the skin deeply, contributing to premature skin aging. They can penetrate glass, clouds, water, and certain clothing, making them a year-round concern.
  • UVB rays are the strongest from 10am to 4pm; overexposure can lead to sunburns and even skin cancer.
  • The UV index is a range of numbers that tell you how intense the sun’s rays are
  • Protecting your skin from both UVA and UVB rays is crucial. This can be achieved by limiting exposure, seeking shade, wearing protective clothing, and maintaining skin health through nutrition, sleep, and stress management.
  • Adding a broad-spectrum sunscreen with non-nano zinc oxide, antioxidants, and our proprietary OS-01 peptide can prevent UV aging while targeting cellular aging at the source.
Key Takeaways:
  • UVA rays are invisible and penetrate the skin deeply, contributing to premature skin aging. They can penetrate glass, clouds, water, and certain clothing, making them a year-round concern.
  • UVB rays are the strongest from 10am to 4pm; overexposure can lead to sunburns and even skin cancer.
  • The UV index is a range of numbers that tell you how intense the sun’s rays are
  • Protecting your skin from both UVA and UVB rays is crucial. This can be achieved by limiting exposure, seeking shade, wearing protective clothing, and maintaining skin health through nutrition, sleep, and stress management.
  • Adding a broad-spectrum sunscreen with non-nano zinc oxide, antioxidants, and our proprietary OS-01 peptide can prevent UV aging while targeting cellular aging at the source.
References
  1. https://pubmed.ncbi.nlm.nih.gov/22356161/
  2. https://www.nejm.org/doi/full/10.1056/NEJM199711133372003
  3. https://www.ncbi.nlm.nih.gov/books/NBK519527/
  4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9368482/
  5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5773794/
  6. https://pubmed.ncbi.nlm.nih.gov/10568250
  7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9447865/
  8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4476387/
  9. https://www.skincancer.org/risk-factors/sunburn/
  10. https://www.epa.gov/sites/default/files/documents/uviguide.pdf
  11. https://www.ncbi.nlm.nih.gov/books/NBK304366/
  12. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7271251/
  13. https://skincancer.net/life-with-skin-cancer/upf-clothing
  14. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8199776/
  15. https://www.sciencedirect.com/science/article/abs/pii/S1567576923000723?via%3Dihub
  16. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3664913/
  17. https://www.umsystem.edu/totalrewards/wellness/how-to-calculate-how-much-water-you-should-drink
  18. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4117056/
  19. https://www.endocrine.org/patient-engagement/endocrine-library/hormones-and-endocrine-function/adrenal-hormones
References
  1. https://pubmed.ncbi.nlm.nih.gov/22356161/
  2. https://www.nejm.org/doi/full/10.1056/NEJM199711133372003
  3. https://www.ncbi.nlm.nih.gov/books/NBK519527/
  4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9368482/
  5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5773794/
  6. https://pubmed.ncbi.nlm.nih.gov/10568250
  7. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9447865/
  8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4476387/
  9. https://www.skincancer.org/risk-factors/sunburn/
  10. https://www.epa.gov/sites/default/files/documents/uviguide.pdf
  11. https://www.ncbi.nlm.nih.gov/books/NBK304366/
  12. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7271251/
  13. https://skincancer.net/life-with-skin-cancer/upf-clothing
  14. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8199776/
  15. https://www.sciencedirect.com/science/article/abs/pii/S1567576923000723?via%3Dihub
  16. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3664913/
  17. https://www.umsystem.edu/totalrewards/wellness/how-to-calculate-how-much-water-you-should-drink
  18. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4117056/
  19. https://www.endocrine.org/patient-engagement/endocrine-library/hormones-and-endocrine-function/adrenal-hormones

Last Updated February 26, 2025

Reviewed by

Alessandra Zonari

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.