Every sunscreen has a sun protection factor, or SPF, which is a measure of its strength or effectiveness. Each of us needs a different SPF, depending on whether, and to what degree, our skin burns or tans. A tan is the direct result of melanin, a brown pigment found in the epidermis that is produced when skin is exposed to sunlight. Melanin protects the skin by absorbing, reflecting and scattering ultraviolet radiation before it penetrates the dermis, or underlying skin. However, armor that it is, melanin can’t prevent all the negative effects of the sun, and is often representative of damage. That’s why we need to use sunscreens. To determine what SPF your skin requires, you must know how long it takes your skin to burn when unprotected and exposed to sunlight. As a rule of thumb, anyone whose skin burns, whether or not it turns into a tan, should use an SPF of 15. Check with your doctor or pharmacist if you are taking antibiotics, antidepressants or antidiuretics. Some of these medications increase your skin’s sensitivity to sunlight and may decrease the time it takes your skin to burn.
Creating A Barrier
When exercising outdoors on a hot, sunny day, light-weight, light-colored clothing combined with plenty of sunscreen on both exposed and unexposed skin is the way to go. However, if overheating isn’t a concern, dark-colored, tightly woven clothing is more effective at blocking UV rays than say, a white Tshirt, which allows UV rays to reach the skin. Another barrier against sun damage comes in the form of eye wear. Protect not only your eyes, but also the skin around them, by wearing sunglasses that block 90 to 100% of the sun’s UV rays. And, last but not least, wear a hat. Though a cap may be more comfortable for jogging, try a wide-brimmed hat that will shade your neck and face while gardening or walking outside.
Everyone Needs A Little Sunlight
It’s been shown that a lack of sunlight can cause depression. After all, most plants won’t even grow without sunshine. And when the sun comes around and makes the days longer, our first instinct is to peel off our sweaters and bask in it. Go ahead. Just take precautions so you won’t have to deal with the unpleasant (and unnecessary) consequences.
- Wear sunscreen every day if you will be outside for more than 20 minutes, even when it’s cloudy.
- Sunscreen should be applied 15 to 30 minutes before going outdoors and reapplied every two hours or after swimming or sweating.
- Limit your exposure to sunlight from 10 a.m. to 4 p.m. during Daylight Savings Time (9 a.m. to 3 p.m. during Standard Time), which is when the sun’s rays are the strongest and most harmful.
- When choosing a sunscreen, look for one with an SPF of 15 or higher that provides broad-spectrum coverage against all ultraviolet light wavelengths.
- Throw out old bottles of sunscreen, which can lose strength after three years.
What SPF Do You Need?
Follow these steps to calculate what SPF you should look for in a sunscreen:
- Determine how many minutes your bare skin can be exposed to the sun before it burns.
- Divide that number of minutes into the total number of minutes you want to remain in the sun.
- The result is the SPF you should look for in a sunscreen. For example, if your unprotected skin burns in 10 minutes, and you plan on being in the sun for three hours, you would need a sunscreen with an SPF of at least 18 (180 minutes divided by 10 minutes).