Q: I find the labels on sunscreen products confusing to understand. What is the difference between UVA and UVB, and what should a person look for when choosing a sunscreen product?
The beautiful, sunny and warm weather this past weekend was a reminder to many New Brunswickers that it’s time to stock up on sunscreen.
About 80 per cent of damaging ultraviolet light exposure occurs between 11:00 a.m. and 3:00 p.m. Take this knowledge into account when choosing outdoor activities, like that Sunday family picnic at the Irving nature park. Wearing ‘sun-safer’ clothing with ultraviolet protective factor (UPF), ultraviolet protective eye wear, and wider-brimmed hats, is especially important during these hours. If you already have sun-damaged skin, avoid going out in the sun during these peak times.
Bottom line: both types of ultraviolet light, UVA and UVB, damage your skin in a way that leads to skin cancer. UVB is connected to sun protection factor (SPF) and is responsible for sunburns. Damage caused by burns is strongly linked to melanoma. UVA is connected to the term ‘broad spectrum’. UVA is associated with many types of skin cancer and may also cause sunburn. Health Canada advises choosing a broad-spectrum product with a minimum SPF of 30. Dermatologists advise using an SPF of 60 or 70, especially for those with pre-existing skin conditions or skin damage.
Sunscreen and sunblock are both types of skin protection from the sun, and each type works effectively if used properly. The key is to choose a product that is a good fit for your lifestyle. If you are not comfortable with the product, you won't use it. Test your product on a small patch of skin first to see if it agrees with your skin.
Sun blocks such as titanium dioxide and zinc dioxide act as physical barriers which tend to be thicker, and more visible on the skin. If you develop pimples easily, this may be too much for your skin. Sunscreens containing active ingredients such as homosalate, oxybenzone, octocrylene, or avobenzon, are creamier but can run off quicker with perspiration and water. If using a spray-on product, spray your hands with the spray and then apply it to your skin. This will help avoid getting the product in your eyes or mouth.
Choose a product with protection against both UVA and UVB, and that is water-resistant. To lessen the risk of chemical skin irritation from your sunscreen, choose a product that is minimally perfumed or, better still, non-perfumed. Choose a product that is labelled non-comedogenic because these are less likely to block or clog the pores of your skin. Lastly, be sure to check the expiry date of your sun care product to ensure that it is still effective.
Regardless of the product you choose, a sufficient amount (i.e. the right dose) needs to be applied to the skin for it to work. The “Teaspoon Rule” is an easy way to remember how much sunscreen to apply. Apply one teaspoon (five mL) of sunscreen for the face, head, and neck, and one teaspoon each to your arms and hands. Apply one teaspoon each to the front torso and back torso, and two teaspoons each to the legs and feet. In total, apply nine teaspoons (45 mL) for the whole body. Apply 30 minutes before going outside and reapply every two hours.
Pharmacists get many questions this time of year about how to best protect children from the dangerous effects of the sun. I found great advice about sun protection for infants and children on the ‘Caring for Kids’ website, developed by the Canadian Paediatric Society.
The best advice is to keep babies out of the sun, especially during peak hours.
- Use a stroller sunshade.
- A sun hat with a wide brim and back flap will help protect the back of the neck.
- Sunglasses with 100% UV (“broad spectrum”) protection to protect the eyes.
- Loose cotton clothing to protect the skin.
As with adults, apply sunscreen with SPF 30+ to all exposed areas of your child's skin at least 30 minutes before heading outside. Remember to put sunblock on ears, nose, back of neck and legs, and tops of feet, and use a lip balm with SPF as well. Consult your pharmacist before using sunscreen on babies under six months of age.
Most importantly, lead by example and remember to protect yourself from the sun. Make protecting yourself against sun exposure a part of your family’s life. For a list of dermatologist-recognized sunscreens, please visit the Canadian Dermatology Association website.
Take the necessary precautions to protect your children and yourself from the sun’s harmful rays, and get out and be active this summer, New Brunswickers. See you out there!
Dr. Kevin McLaughlin (PharmD, BScPharm, BSc, ACPR) practices at Kennebecasis Drugs, in Rothesay N.B. His opinions expressed in this column are published for educational and informational purposes only, and are not intended as a diagnosis, treatment or as a substitute for professional medical advice, diagnosis or treatment.