We all know we need to wear sunscreen. Not only does it protect us from skin cancer, it protects against overall sun damage to the skin. And as you age you can tell those that constantly wore sunscreen and stayed out of the sun during peak hours, and those that baked in the sun. While certain skin types are more susceptible to sun damage than others, you can do a lot to protect yourself when you know a bit more about sunscreen, how to apply it and avoid common mistakes.

1. UVA and UVB rays are different. UVB rays are the rays of the sun that cause you the pain, meaning they’re what actually causes you to burn. While UVA rays actually cause the sun damage that can cause skin cancer. Protect yourself from both using broad spectrum sunscreen that contains both UVA/UVB protection.

2. SPF has a meaning. SPF stands for Sun Protection Factor and refers to the theoretical amount of time you can stay in the sun without getting sunburned. For example, an SPF of 15 would allow you to stay in the sun 15 times longer than you could without protection. So, if your skin starts to redden in 20 minutes without sun block, applying a product with SPF 15 increases that time by a factor of 15, meaning you could stay in the sun for 20 minutes times 15, which would be 300 minutes. In addition, a higher SPF blocks out more rays—a product with an SPF of 15 will filter out approximately 93 percent of UVB rays; SPF 30 filters out about 97 percent.

When to use SPF 15? Best used for everyday protection all year long and when outside for a limited amount of time such as a quick walk or drive from place to place. Even on sunny winter days, some type of sun protection is still needed.

When to use SPF 30 or higher? Best used when outdoors for long periods of time, such as outdoor activities, running, hiking, biking or spending time at a pool or beach.

3. Certain parts of the body get more sun. The parts of your body that are not hidden under shadows get the most sun. Your nose, chest, and the tops of your feet don’t have any shadow, so make sure you protect these parts of the body with extra SPF protection. Proper sun protection isn't complicated but can take time to make sure that ALL of your exposed body parts are covered, even your ear lobes, scalp of your head and along your hairline.

4. Waterproof sunscreen isn't really a thing! As soon as you towel off after swimming or sweating from exercise, you're rubbing off the sunscreen you've applied. Therefore sunscreens shouldn't really be considered fully waterproof and  need to be applied often, especially when outside for extended periods of time. It's often recommended to re-apply every 2 hours or after getting wet.

It's important that you understand how to protect yourself so that you can avoid premature aging of the skin, skin damage and worst of all, skin cancer.

Updated by Written by Alyssa Rolnick, Co-Founder of Zax’s Original Products, Registered Dietitian and Mother of a very busy household.