It is summer and you are at the beach or in the pool. UPS! You forgot to buy sunscreen. This can be a daunting task in determining which sun protection is right for you. No problem, I have the solution … don’t go out … just kidding! Anyway, head down to the tanning / sunscreen section of the local drugstore and this is where the fun begins. You wonder: what the heck is SPF, UVA, UVB? Let’s analyze it …
What is SPF?
SPF is defined as a sun protection factor. The higher the SPF number, the better protection against the sun’s harmful UVB rays. The SPF number lets you know how much longer you can stay out of the sun without getting burned. So if it takes a person 10 minutes to burn, an SPF 15 will allow them to stay in the sun 15 times longer without burning. Most dermatologists recommend wearing an SPF of 15 or higher for maximum protection.
The sunscreen label will indicate UVA or UVB protection.
UVA rays are responsible for increasing the speed of aging and wrinkles in the skin from the sun. Overexposure to UVA rays can also cause skin cancer. UVB rays are responsible for sunburn and skin cancer. You will want to choose a product that states “UVA / UVB” protection or has a “broad spectrum” protector.
Which one should you decide? Waterproof or Water resistant.
If you are looking for a sunscreen to use while in the water, choose a sunscreen that is “waterproof” or “water resistant.” “Waterproof” sunscreen should provide protection in the water for approximately 60 minutes, while “waterproof” provides only 30 minutes of protection.
So how do those sunscreen products work, and what sunscreen ingredients protect against these two types of UV radiation?
Physical sunscreens that contain zinc oxide or titanium dioxide protect against UVB and UVA rays. However, zinc oxide blocks more UV radiation than titanium dioxide and is therefore the preferred ingredient. Some chemical sunscreens can also block UVA rays. Octocylene is a chemical known as cinnamate that has both UVA and UVB absorbing properties, and benzophenones (such as avobenzone) can also absorb UVA and UVB rays.
How should sunscreens be applied to the skin?
It’s a good rule of thumb to apply sunscreen very generously. Sunscreen should be applied about 20 minutes before going outside to allow time for it to penetrate and take effect.
So does water or perspiration wash away sunscreen?
Yes. Therefore, sunscreen should be reapplied at least every hour when you are outdoors for an extended period and after swimming, bathing, exercising, sweating a lot, or drying off with a towel. Water and perspiration resistant sunscreens are available. However, even your protection won’t last indefinitely.