In Canada, sunlight is strong enough to cause skin cancer and premature aging of the skin. Sunscreen is a product that protects the skin from the damaging ultraviolet radiation (UVR) from the sun. Sunscreen comes in many forms, such as lotion, cream, gel, spray or stick.
Sunscreen absorbs UV rays and prevents them from penetrating the skin. Make sure your sunscreen offers protection against both UVA and UVB rays (usually labelled “broad spectrum”). All sunscreens allow some UV rays to penetrate your skin, but broad-spectrum will give you the best protection.
Sun Protection Factor (SPF)
Sunscreens are rated by the strength of their sun protection factor (SPF). The SPF number refers to the product’s ability to screen or block out the sun’s ultraviolet B (UVB) rays. Sunscreens are available with a SPF ranging from 2 to at least 100. Sunscreens with higher SPF ratings block slightly more UVB rays, but none offer 100% protection.
- SPF 15 sunscreen blocks 93% of UVB rays.
- SPF 30 and higher sunscreen blocks 97% of UVB rays. They are not twice as effective as SPF 15.
- Regardless of the SPF, the sunscreen’s effectiveness can be affected by how much you use, your skin type and the length of time and intensity of UVR you are exposed to.
How to Use Sunscreen
- Check the UV index before you go outside. The higher the UV index number, the stronger the sun’s rays and the greater the need to take precautions. Wear protective clothing, sunglasses and sunscreen, especially when the UV index is 3 or more.
- Remember, no sunscreen can block all of the sun’s rays, so use sunscreen as a backup in your sun protection plan.
- Use sunscreen along with shade, clothing and hats, not instead of them.
- Remember that sunscreens are not meant to be used so that you can stay out in the sun longer. They are meant to increase your protection when you have to be outside.
- Use a sunscreen with an SPF 15 or higher.
- Use a sunscreen with SPF 30 if you work outside or plan to be outside for most of the day.
- Apply a generous amount of sunscreen to clean, dry skin at least 20 minutes before you go outside to allow the active ingredients to soak into your skin. Don’t forget to put sunscreen on your ears, nose, neck and any bald spots and the tops of your feet.
- Put sunscreen on first, before any make-up or insect repellent.
- If you’re going to be in the water, make sure your sunscreen is water-resistant.
- Your lips need protection too. Use an SPF 15 lip balm and reapply as needed.
- Follow the instructions for reapplying sunscreen, especially after swimming, exercising or sweating.
- Apply sunscreen even on cloudy days because UV rays can still pass through thin or scattered layers of cloud.
- Don’t forget to apply sunscreen during the winter months.
- Some products combine sunscreen with make-up or moisturizer. Always check that the sunscreen is broad spectrum, and follow the directions for how much to apply and how often. If you’re not sure that the sunscreen protects you from both UVA and UVB rays or the packaging doesn’t include directions, you may want to use a broad-spectrum sunscreen along with your make-up or moisturizer.
- Sunscreens have an expiry date that is usually visible on the container. Sunscreens contain chemicals and they should not be used after the expiry date because they may not work as well. Sunscreens can be affected by extreme changes in temperature. If it has been frozen or overheated, throw it out. If the sunscreen has changed colour or smell, throw it out.
Choosing a sunscreen
Try different sunscreens until you find one that works best for you. Talk to your esthetician, doctor or pharmacist if you need help choosing a sunscreen.
Health Canada regulates the safety and quality of sunscreens in Canada. Sunscreen products are classified as drugs and must meet Canadian requirements.