A serious sunburn increases your risk of skin cancer and the more times you’re burnt, the higher the risk. But what is a sunburn and why is it so damaging?

A sunburn is a radiation burn. While similar to a regular burn in some ways, it isn’t caused by heat. Instead, a sunburn occurs when our skin is exposed to too much UV radiation and DNA damage has occurred.

What is Happening During a Sunburn

1. Light absorbing molecules in our skin, like DNA, absorb UV light. Too much exposure can cause damage to cellular DNA which causes the cells to die off.
2. An inflammatory response is triggered and the body increases blood flow to the area to bring white blood cells to the site of injury to clean away debris and repair.
3. The blood flow as well as the release of histamines and inflammatory molecules cause the redness as well as swelling, edema, itching, and pain.
4. After a few days, the dead skin cells will start to slough off and you may see visible peeling.

While skin cells dying off may sound bad, this is actually a good thing. When DNA becomes damaged, our skin has two options available: kill off the entire cell and basically get this damaged DNA out of here or repair the damage to the DNA. The top layer of our skin rapidly divides and can quickly replace these dead cells anyway while damaged DNA that hangs around and isn’t repaired means there is a risk of mutation.

Cell mutation occurs when there is a change to our DNA sequence. DNA is found in the nucleus (the control center of the cell) and is essentially a set of instructions that the body uses to create proteins and new cells. If there’s just one change in the instructions, the end product could be different and the mutation is passed on. As mutations accumulate, cells have a higher risk of becoming cancerous.

Like thermal burns from heat, sunburns can also range in severity. Minor sunburns can be handled with at-home interventions but you should seek medical attention for severe sunburns.

Mild sunburn. Skin is pink or red and the damage only reaches the upper skin layers.

Moderate sunburn. Skin is very red and the sunburn has reached the dermis. Swelling and blistering can occur. Headaches are also common.

Severe sunburn. While rare, this type of sunburn is very serious and can cause infection and scarring as well as damage to the nerves.

Risk Factors

Sunburns aren’t caused by how long you’re in the sun but rather the amount of UV radiation you’re exposed to. That means that the higher the UV index, the quicker you’ll burn when unprotected. There are also other risk factors that can make you more prone to sunburn.

Ozone Depletion. The ozone layer is more depleted in certain parts of the world, allowing more UV radiation to reach the surface of the planet.

Medications. Make sure that you are informed on the medications you take as some can make your skin more sensitive to the sun.

Skin Tone. Fair skin tones with blue or green eyes and blonde or red hair are usually the most at risk when it comes to sunburns. While melanin isn’t a substitute for sun protection, it does mean that deeper skin tones have some natural resistance to sunburn.

Environment. Factors like the season, altitude, cloud cover, presence of snow, closeness to the equator, and time of day can all influence the amount of UV you’re exposed to.

Sun Habits. If you don’t wear sunscreen or protective clothing and practice other safe sun habits like seeking shade midday, you can risk your skin.

Sun Burn First Aid

Avoiding sunburns entirely is always the goal and we’ll get into prevention next. But if it does happen, let’s talk about what you should actually do - and what home remedies do more harm than good.

Immediately after:

• Calm and cool the skin. A cool compress is perfect but you can use aloe vera gel if you prefer, it’s just not very researched.
• Petroleum jelly can be applied to protect the skin and to aid in healing after you’ve cooled the skin down.
• Drink lots of water as burned skin may not be able to retain water as well.
• OTC medications like aspirin or ibuprofen can be taken for pain and swelling if you’re a suitable candidate and there’s no contraindications. 

During the healing process:

• Avoid the sun so you don’t cause more damage while the skin is healing.
• Continue to apply petroleum jelly to areas that are raw or peeling.
• If the skin is very itchy while it’s peeling, some people find antihistamines or topical hydrocortisone helpful. Always make sure they’re safe for you to take and consult with a provider if you have questions.
• Wear loose clothing that doesn’t rub or constrict.

After the sunburn is healed:

• Retinoids and ascorbic acid can help repair UV damage but sunscreen use is best as it will allow the skin to focus on repairing itself.
• If you experience hyper pigmentation, you can discuss a pigment inhibitor like hydroquinone with your provider.

Remember, seek medical attention for more serious sunburns. Even if the sunburn appears mild, get medical treatment if you experience a fever, confusion, extreme swelling, or signs of infection like pus or streaking.

Home Remedies

There are many home remedies for sunburns shared online and by well meaning family members and friends. We’ve divided them up into which are harmless and probably okay to use vs which ones to avoid.

Likely Harmless:

• Oatmeal bath with cool water.
• Aloe vera gel.
• After sun products, just avoid fragrance and anything irritating.

Pass on These:

• Vinegar, ketchup, or anything else that is acidic.
• Baking soda, while potentially soothing, is too alkaline.
• Noxema. While the cooling effect can feel really nice for sunburns, look for soothing options that don’t have fragrance.

Prevention

While sunburns do happen and it doesn’t do any good to beat yourself up, it’s always best to avoid them entirely whenever possible.

According to the Skin Cancer Foundation:

“5 or more sunburns doubles your risk of melanoma.”

“1 in 5 Americans will develop skin cancer by age 70.”

“About 90 percent of nonmelanoma skin cancers are associated with exposure to UV radiation from the sun.”

“More than 2 people die of skin cancer in the U.S. every hour.”

Safe sun habits save lives and are most effective when they become part of your daily routine. Sun protection also encompasses more than just sunscreen alone as no sunscreen protects 100% and research has shown that we don’t do the best job applying sunscreen perfectly either. At the same time, this blog is not about telling people to hide in their homes and avoid the sun like a vampire. You can enjoy the outdoors and still protect your skin.

Use a broad spectrum, SPF 50 sunscreen. If you’re swimming or sweating, you’ll want something water resistant.

Skip sunscreen sticks and sprays unless it’s for hard to reach areas or reapplying over makeup. Avoid sunscreen powders entirely.

Make sure you apply the 2 mg sunscreen per cm2 of skin. This is about ½ teaspoon for the face, neck, and ears or a shot glass for the body.

Reapply every 2-3 hours you’re exposed to the sun.

Combine sunscreen with other sun protection methods. This can include UPF rated clothing, sun glasses, and sun umbrellas as well as seeking shade and avoiding the sun during peak hours.

Antioxidants and supplements like Heliocare can also be helpful, particularly if you have very skin or sun sensitivity.

References 

https://www.skincancer.org/skin-cancer-information/skin-cancer-facts/

1. https://emedicine.medscape.com/article/773203-overview?form=fpf#a2
2. https://www.ncbi.nlm.nih.gov/books/NBK534837/

Mira is a skincare educator, blogger, and the content creator behind Skin Science by Mira and The Skincare Forum on Facebook. While skincare keeps her busy, she’s also pursuing her degree in Nursing and loves to spend her free time hiking.  As a content writer for Stratia Skin, Mira shares her evidence-based approach to skincare topics and a passion for making science accessible.