San Diego dermatologist Dr. Anne Truitt shares important advice from the American Academy of Dermatology. Dr. Truitt is a Mohs skin cancer surgeon and immediate past president of the San Diego Dermatological Society.

Skin cancer is the most common cancer in the United States, affecting one in five Americans in their lifetime. However, in a recent survey, the American Academy of Dermatology found that not everyone is applying their sunscreen correctly — leaving people vulnerable to dangerous ultraviolet radiation from the sun. For example, the AAD found that only about a third of Americans reapply their sunscreen every two hours while outside. Since sunscreen wears off, incorrect usage can leave you unprotected and susceptible to skin cancer.
 
To protect your skin and reduce your risk of skin cancer, below are five common sunscreen mistakes — and how to avoid them:
 

  1. Ignoring the label. There are a variety of sunscreens on the market. To effectively protect yourself from the sun, the AAD recommends looking for sunscreens that are broad-spectrum, water-resistant and have an SPF of 30 or higher.  I additionally recommend the ingredient zinc oxide at 5% or higher as it gives the best broad-spectrum coverage, and it is reef safe.

  2. Using too little. Most people only apply 25-50% of the recommended amount of sunscreen. However, to fully cover their body, most adults need about one ounce of sunscreen – or enough to fill a shot glass. Apply enough sunscreen to cover all skin that isn’t covered by clothing. Apply the sunscreen 15 minutes before going outdoors, and reapply every two hours while outdoors or after swimming or sweating.  If using a spray sunscreen, make sure to rub it in.

  3. Applying only in sunny weather. Alarmingly, the AAD found that only about 20% of Americans use sunscreen on cloudy days. However, the sun emits harmful UV rays all year long. Even on cloudy days, up to 80% of UV rays can penetrate your skin. To protect your skin and reduce your risk of skin cancer, apply sunscreen every time you are outside, even on cloudy days.

  4. Using an old bottle. The FDA requires that all sunscreens retain their original strength for at least three years. Throw out your sunscreen if it’s expired or you’re unsure how long you’ve had it. In the future, if you buy a sunscreen that lacks an expiration date, write the purchase date directly on the bottle so that you know when to toss it out.

  5. Relying solely on sunscreen. Since no sunscreen can block 100% of the sun’s UV rays, it’s also important to seek shade and wear sun-protective clothing, including a lightweight, long-sleeved shirt, pants, a wide-brimmed hat and sunglasses with UV protection, when possible. For more effective sun protection, select clothing with an ultraviolet protection factor (UPF) label.

  6. Don’t forget to protect the ears and tops of feet.  The ears and dorsal feet (think how often you are barefoot or wearing sandals in the summer) are often left unprotected and become the victim of skin cancer.  Sunscreen, hats, and protective clothing are the best protection.

Enjoy your summer while keeping healthy, younger-looking skin.