Q: What’s the right way to apply sunscreen?
A: The most important way to apply sunscreen is to actually put it on the skin! The risk of development of skin cancers is related to the amount of ultraviolet light exposure. It is wise to protect yourself and your skin with daily applications of sunscreen. Here are a few key points:
- How much to use? Most people do not use the appropriate amount of sunscreen, which is about 1 ounce per application. This is the quantity needed to fill a shot glass…quite a large amount! One clue that the amount of sunscreen you are applying is probably too little is if a bottle of sunscreen lasts more than one summer.
- When to apply? Ideally, sunscreen should be applied to dry skin prior to going out in the sun. Application 15-30 minutes before sun exposure is best, as some sunscreens (chemical blockers) need to be absorbed into the skin in order to take effect. It is important to remember that sunscreens need to be reapplied as well. Sunscreens can wash off in the water (even water-resistant sunscreens) and can rub off with friction. Reapplication every 2 hours is important for effective protection.
- What type to use? There are two main classes of sunscreens: chemical blockers and physical blockers. Chemical blockers (like avobenzone, oxybenzone, etc) are absorbed into the skin and absorb ultraviolet rays. Physical blockers (like zinc oxide and titanium dioxide) sit on the surface of the skin and reflect the sun’s rays. Often broad-spectrum sunscreens contain a combination of both chemical and physical blockers. Some people can have a sensitivity to certain sunscreen ingredients, usually one of the chemical blockers. For those individuals, choosing a purely physical blocker is probably the best decision for sun protection.
- Where to apply? It is important to apply sunscreen to all exposed skin, not forgetting the ears, back of the neck, and tops of the feet. Additionally, use of sunscreens in a lip balm formulation is critical for avoiding sunburn of the lips. It is also important to note that sitting under a beach umbrella may not offer full protection from the sun’s rays, as ultraviolet light can reflect off sand and water, causing sunburn even in the “shade.”