Why SPF Should Be Your BFF

From our friends at Tufts Medical Center 

Hard to believe, but summer is here.  How much do you know about skin protection and the dangers of sun exposure? Even though the sun feels great after a long winter, sunscreen is critical (and not just seasonally). Chief of Dermatology at Tufts Medical Center, Dr. Clarissa Yang, spoke to us recently and answered our many questions about sunshine in the city and how to protect our skin.

Q: How does SPF work?

A: When using sunscreen, the SPF (Sunscreen Protection Factor) is a ratio of how much longer you can stay in the sun without getting sunburned. For example, if you sunburn in 1 hour, application of SPF30 would theoretically allow you to stay in the sun for 30 times as long (so, 30 hours) without burning. However, between sweat, exercise, wiping or rubbing against a towel, going in and out of the water, plus some of the enzymatic degradation in the skin, sunscreen breaks down quickly and no longer holds that 30x longer effectiveness (see my recommendation on reapplication next).

Q: How high of an SPF should we look for and how often should it be applied?

A: Look for sunscreens with at least an SPF 30 and apply 30 minutes prior to going outdoors. Try to stay out of the direct sunlight between 10AM and 4PM, which is when the sunburn rays are the strongest. It is important to reapply at least every two hours and always after swimming or heavy sweating/exercise.

Q: Why is it so important to prevent sunburns? 

A: Sunburns increase your risk of skin cancer and aging. You are most at risk for developing skin cancer if you have a history of multiple sunburns. Other risk factors include:

You have blue or green eyes with light skin

You have a family history of melanoma

You have a history of chronic sun exposure

You have a high number of moles

You have had biopsy-proven atypical moles

You have a history of tanning bed exposure

Q: Can I ever use a tanning bed even if it is just for a base tan?

A: No, even use of one sun tanning bed exposure has been shown to increase risk of skin cancer development.

Q: I use sunscreen religiously, but I have so many of the skin cancer risk factors you just listed. Is there anything else I can do to protect myself from the sun?

A: Sun protection with clothing is even better than sunscreen, so cover up when you can. Maintaining a good immune system is also important. You can do this by eating a healthy diet full of antioxidants, and getting plenty of sleep. Using topical antioxidants such as vitamin C, E, ferulic acid and retinoids can help as well.

Q: What are some skin cancer symptoms I should look out for?

A: There are different types of skin cancer. The most well-known is melanoma, a tumor of melanocytes. Always remember the ABCDE’s of melanoma:

Asymmetry

Border irregularity

Color changes

Diameter >6mm

Evolution (any changes – itching, bleeding, pain, enlarging)

Non-melanoma skin cancers such as basal cell/squamous cell carcinomas are typically pink lesions that do not resolve.  They get bigger with time and may bleed spontaneously or scale. It is important to note that incidence of skin cancer goes up with age.

Q: Is there a cure for melanoma/skin cancers?

A: For many decades, late-stage melanoma had a low survival rate – only 6-10% survived within a five year timespan.  However, in the last eight years, there have been significant advances in treatment options in immune and targeted therapy for melanoma. This has made significant differences in patient survivals; however, it is still so important to catch it early. When caught in the early stages, skin cancers are curable through surgical excision, so make sure to do regular self-checks and to schedule annual skin screenings