Sunprotection

Summer is upon us, and that means fun in the sun!  Let’s remember to be safe and smart, taking measures to prevent sunburn in the short-term, and skin cancer, premature aging, and unsightly discoloration in the long-term.

AA sublocksunsmarties_cabana_tent

Everyone, regardless of skin tone, is susceptible to the harmful effects of the sun’s rays. People with lighter skin types who burn easily should be especially cautious.

Ultraviolent (UV) radiation (290 to 400 nm) causes skin damage. Within that spectrum, UVB (290 to 320 nm) is responsible for sunburn (“B” for “burn”), inflammation, skin discoloration, and cancer formation. UVA (320 to 400 nm) is responsible for photoaging (“A” for “aging”), skin darkening, and possibly cancer formation.

The UV Index, on a scale of 0-11, is a forecast of how risky the sun exposure is that day, and is calculated by zipcode here or here. Read this or this to learn how to interpret the UV index.

beach hat

To protect your skin against UV radiation:

A)   Avoid the sun during peak hours: stay inside or seek shade between 11 am and 3pm. This is especially important at latitudes closer to the equator.

B)   Wear sun protective clothing:

  1. Sunglasses: Look for lenses that block 99-100% of UV rays. UV rays can lead to eye damage including cataracts, macular degeneration, photokeratitis (“sunburn of the eye”). For more: Mayo Clinic, All About Vision.
  2. Hats: especially wide-brimmed.
  3. Long-sleeve garments: Fabrics are rated on their ultraviolent protection factor (UPF).

C)   Apply sunscreen: these contain filters that reflect or absorb UV rays. They fall into two categories: organic (aka chemical), or inorganic (aka physical).

kids under tent

Here are some tips for finding and using sunscreen:

1)   Look for “broad-spectrum” on the label: these protect against both UVB and UVA. Make sure it contains at least one of the following in the ingredients list: avobenzone, zinc oxide, or titanium dioxide.

2)   Look for SPF 15 or above, per the FDA (but better 30 or higher). When enough sunscreen is applied, SPF 15 will absorb about 93% of UV radiation; SP 30 will absorb 97%, and SPF 50 98%.

3)   Apply daily, even on a cloudy day. Keep your sunscreen of choice next to your toothbrush so you apply it as part of your morning routine.

4)   Look for cosmetics or lotions with SPF15+. Choosing a moisturizer or a foundation with SPF to use as your daily sunprotective product may help you stick with your sunscreen routine.

5)   Apply 15-30 minutes before going out in the sun. This allows a protective film to form on the skin.

6)   Apply sunscreen liberally before outdoor activities to all sun-exposed areas. For the average adult, this means applying 1 oz (30mL), or one shot glass full.

7)   Reapply often: at least every two hours when out in the sun. Reapply after swimming, water sports, or sweating.

8)   Look for water-resistant sunscreens for days you will be in the water. Continue to reapply, however, after each swim.

9)   If you have sensitive skin, inorganic or physical sunscreens may be best for you, as they are less irritating. These contain mineral compounds such as zinc oxide and/or titanium dioxide. These products are also preferred for use in children.

10) Find the form you are most likely to use. Sunscreens come in a variety of forms: creams (greasier, thicker), lotions (thinner), liquids, sprays, gels, roll-on sticks. Find the vehicle that works for you. The best sunscreen is the one that you will use.

Vitamin D: Some people are concerned that they will not produce enough 25-hydroxyvitamin D if they do not get enough sun. Vitamin D, however, is readily available in certain foods (milk, fortified juices, salmon) or in supplement form. Vitamin D insufficiency is a common problem, but the safest way to combat it is by taking a daily supplement.

Thanks for reading, and enjoy your summer!

-Alex

 More links: Consumer info on Sunscreens, Teacher Resources, SunSmart Australia

References:

Baron ED, Elmets CA, Corona R. Selection of sunscreen and sun-protective measures. UpToDate April 01, 2014. Accessed May 13, 2014.

Young AR, Tewari A, Dellavalle RP, Danzl DF, Corona R. Sunburn. UpToDate May 01, 2014. Accessed May 13, 2014.