What Really Happens When Your Skin Gets A Sunburn

dermatologist explains what happens to your skin when you get sunburned

What really happens to your skin when you get a sunburn - if you get a sunburn?? Summer is almost here for those of us in the Northern Hemisphere. The days are getting longer. It's hard to resist the inviting sun, and join friends in some of our favorite outdoor activities such as swimming, picnicking, cycling, hiking, or a marathon run.

It's healthy to get outside and participate in activities AND you must also be mindful of the exposure of the sun to your skin. Dr. Bailey has devoted an entire blog category to "Sun Protection Advice" because she wants to help you take good care of your skin. Since May is Skin Cancer Awareness Month, it is the perfect time to discuss what occurs to your skin when it becomes "sunburned."

Sunburn skin under the microscope

UV rays cause redness and swelling of the skin due to dilation of the skin's capillaries and migration of white blood cells into the inflamed and injured skin. The capillary vasodilation starts within 30 minutes and becomes maximal at 24 hours after exposure. White blood cells take 1 to 2 days to migrate into the tender skin. 

A sunburn is an injury to the skin or other tissues of the body due to radiation from the sun.

The degree of the burn can depend on several factors such as:

  • length of time in the sun,
  • location in the world relative to the sun or impaired atmospheric areas,
  • and the amount of melanin in the skin. 

UV light is a combination of different types of radiation based on the varying wavelengths.

It is important to understand the potential effects of UV light and how sunburns occur.  Although sunburned skin indicates too much sun exposure for your skin, many wavelengths of UV light damage the skin but do not result in a sunburn.

  • UVA - long wavelength: damages elastic tissue (ages skin) and may produce scaly and crusty nodules on the skin (actinic keratosis). It also disrupts the skin on a cellular level leading to skin cancers such as melanoma. The intensity does not vary throughout the day, but is the same whenever sun is present (no exposure occurs at night).
  • UVB - middle wavelength: causes cumulative "heating" effects on the skin leading to sunburn. It is an important wavelength in the development of skin cancer. The intensity of UVB varies in the day, increasing as the sun is closer to earth.
  • UVC - short wavelength: blocked by the atmosphere, currently, on earth, there is not a risk for exposure.

How does melanin help protect skin from sunburn?

The melanin in your skin is the pigment which determines your complexion coloration. It has an interesting relationship with UV light.  Melanin effectively dissipates and absorbs UV light, specifically UVB. The more melanin you have, the darker your skin tone. This is why darker skin tones do not experience sunburns as frequently as lighter skin tones.

Interestingly, when the skin is experiencing damage from UVA rays as opposed to UVB rays, it redistributes the melanin already in the skin but does not increase production of melanin for protection - you look tanner but have no increased UV protection.

This is a really important fact to digest. Read it again. Know that a UVA tan does not provide any additional protection from UV damage. Also, a tan or dark skin does not provide full protection from UV light. And, melanin does not affect the absorption of UVA light, a main factor for skin cancer. This is why Dr. Bailey advocates for everyone to wear sunscreen 365 days out of the year!!!

How to Prevent a Sunburn?

This should be an easy answer: wear broadband sunscreen and use other sun protective behavior! Despite evidence-based research proving the protective properties of broadband sunscreen against skin cancer and aging, many people still choose not to wear it. Although there are other methods to protect your skin, nothing is as effective as a broadband sunscreen because of the convenience factor. If you need help selecting a sunscreen, check out Dr. Bailey's sun protection tools. Find dermatologist-approved sunscreens for every skin type and preference, practical and effective sunhats, UPF 50 sun umbrellas and even a simple UV ray detecting gizmo.  

prevent sunburn with this

Use a combination of important dermatologist-approved strategies to sun protect your skin include:

  • Avoiding sun exposure at highest UVB intensity: 10am - 2pm std time, or 11am-3pm daylight savings time. 
  • Protective clothing: wide-brimmed hats, sun glasses, long-sleeved shirts. Dr. Bailey has great recommendations as well as selections on the website.
  • Shade: from either umbrellas or large overhanging tress. However, be aware of the incomplete protection shade provides, which Dr. Bailey explains in her original blog: Shade Sun Protection, Is It Good Enough?

However, these methods should always be paired with wearing sunscreen. Also, read the label for how often re-application is needed. Overtime, sunscreen is sweated away, rubs off and is even slowly degraded as it blocks light - thus you need a second or even third application when spending all day outdoors.

How to Treat Sunburns?

how to use aloe to treat a sunburn

If you find yourself in the unfortunate situation of developing a sunburn because you forgot to apply sunscreen or ran out unexpectedly (I can't count how many times I brought a tube of sunscreen only to discover one squeeze left!), here are a few tips to reduce the skin injury and optimize healing:

  1. Cool the skin in cool/lukewarm water and apply moisturizer within three minutes: the sun sapped your skin of its natural moisturizer and keeping the skin properly hydrated will promote healing. The skin will start to peel eventually, but continue to apply moisturizer after bathing to help lock in the moisture.
  2. Take an anti-inflammatory agent: aspirin - Anti-inflammatory agents help reduce redness associated with inflamed skin. In case of sunburn, it must be taken prior or immediately after sunburn before significant redness develops. However, you must be careful to not exceed the maximum dosage in a day or for given period of time, or you may experience nausea and in extreme cases seizure.
  3. Pure aloe vera gel: this is generally the most commonly used and even marketed item for sunburn treatment. The soothing sensation decreases the discomfort of sunburned skin. Avoid gels with topical anesthetic as this may cause an allergic reaction
  4. Prescription topical cortisone creams: If applied within 6 hours of the sunburn, it may provide relief but it requires doctor's supervision.
  5. Natural Remedies: Ice, cucumbers, and many others provide soothing relief or draw out heat from a sunburn. Dr. Bailey details more natural remedies here.

Now some sunburns may require medical treatment. If your sunburn starts to develop blisters or even has areas of bleeding, call your doctor STAT. Depending on the level of burn, a sunburn may require different medical interventions and treatment to prevent skin infections since the skin barrier is severely impaired.

If you have found these tips about sunburn prevention and treatment helpful, please share them with friends and family to help them protect their skin this year.