Causes, Risk Factors and Prevention of Sunburn

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It is important to remember that, regardless of skin color, temperature or weather conditions, daily use of a broad-spectrum SPF of 30 or higher on exposed areas is important. It does seem counterintuitive to think about sunscreen in a blizzard, but the snow (like the water and sand) reflects 80 percent of cancerous ultraviolet (UV) rays. Although anyone can get sunburned, having lighter skin or spending long periods of time in high-intensity sun puts you at a higher risk.

Having Fair Skin

Melanin is the pigment in our skin that is responsible for protecting us from UV light. Based on biological melanin content, individuals with fair skin have a “natural” SPF of about 3.4, while those with medium-brown skin have a built in SPF of approximately 13.4. The more melanin someone has, the more protected they are against sunburn. So red- or blond-haired people with light eyes are particularly susceptible to getting burned because of their lower melanin content.

Not Using Sunscreen

The American Academy of Dermatology recommends daily use of a broad-spectrum SPF of 30 or higher every two hours or after swimming or excessive sweating. In this case, a little dab won’t do. To get good coverage, one should apply sunscreen in the amount of a shot glass over their entire body. Also, the American Academy of Dermatology recommends applying sunscreen 15 minutes prior to sun exposure for maximum efficacy. Anything less than this, in terms of timing or amount of SPF applied, could lead to sunburn. Judicious sun protection is particularly important for those who vacation or live in hotter climates or at higher altitudes.

Working Outdoors

Jobs that require a lot of outdoor time are also a risk factor for sunburn. The issue here is twofold. First, it is often difficult to seek shade if the task at hand is directly in the sun. Second, reapplication of sunscreen every two hours is often perceived as onerous and impractical. This is an instance when use of sun protective clothing, such as broad-brimmed hats and sunglasses, can be helpful.

Mixing Alcohol With Outdoor Recreation

Having a beer beachside may be the perfect setup for sunburn. Oftentimes when alcohol is part of the equation, people forget to reapply sunscreen every two hours. This may be also true of backyard barbecues and social sporting events.


There are certain medications that predispose to sunburn. Common culprits include antibiotics in the tetracycline family (this includes minocycline and doxycycline) as well as diuretics like hydrochlorothiazide used for treatment of high blood pressure. The UV light that comes through a car window is enough to cause sunburn in people on these medications. Always ask your doctor whether photosensitization is a side effect of the prescription they are giving you.

Lying Out or Using Tanning Beds

It is no secret that lying out in the sun is a perfect setup for sunburn. There is a common misconception that artificial UV light, in the form of tanning booths, is somehow better for the skin. The truth is that these devices deliver 12 times the amount of UVA light that comes from the sun. Dermatologists advise strongly against both scenarios because of the high potential for sunburn and the development of skin cancer.

Tips on Sunburn Prevention:

-Avoid the sun between 10 a.m. and 4 p.m.

-Seek shade whenever possible.

-Before going outside, apply a broad-spectrum SPF of 30 or higher, and reapply every two hours or after swimming or excessive sweating. Remember to apply liberally — the amount of a shot glass over the entire body.

-Do not forget to apply SPF to parts of the body that are commonly missed, such as the scalp, eyelids, ears, lips, nose and tops of the feet. Also apply sunscreen under your clothing unless it is already designated as sun-protective. UV light can burn your skin through a shirt.

-Remember to wear sunscreen in the winter.

-Wear sunglasses, sun-protective clothing (look for the designation UPF 50) and a broad-brimmed hat.

-Do not lie out to try to get tan, and avoid tanning booths.