Whether heading outside for a walk in the sun or to the beach for vacation, it is important to protect your skin. Sunscreen products come in many different formulations, and lotion, cream, spray, stick, oil, or serum are a few examples. Sunscreen also comes in varying levels of SPF, or sun protection factor.What does the SPF level mean?
The Sun Protection Factor level indicates a general measure of time that the sunscreen will protect your skin from UVB (short ultraviolet rays). A higher SPF rating provides more protection against UVB rays. Sunscreen products come in a range from SPF 2 to SPF 70. SPF 30 is one of the most commonly used types of sunscreen lotion. SPF is calculated based on generalizations about how many minutes of sun exposure that a person can have until their skin burns. For example, if a person burns without sunscreen in ten minutes, but applies an SPF 30 lotion, typically that person could spend 300 minutes, or five hours, in the sun without burning if they have applied enough product.
Factors affecting the power of SPF are listed here:
- How much product is applied
- How long you're in the water
- How much you sweat
- How much lotion or perfume you've previously applied
A broad spectrum sunscreen protects the skin against both the UVA and UVB rays. The ingredients zinc oxide, titanium dioxide, avobenzone, ecamsule, and oxybenzone could be added to normal sunscreen lotion to protect against UVA rays. The SPF rating applies only to UVB rays, so broad spectrum sunscreen can ensure additional skin protection. It is important to check the ingredient lists if you are looking for specific types of protection.What are the two types of UV (ultraviolet) rays?
UVA rays are long ultraviolet rays that reach into the inner layers of skin (the dermis). UVB rays are short ultraviolet rays that reach into the outer layers of skin (the epidermis). UVB ray intensity can vary throughout the day.How often should you apply or reapply sunscreen lotion?
The first rule of thumb is to apply before going outside. Water can wash off the sunscreen, so if you plan to swim or be around water, it is recommended to reapply often, at least every hour. If you are not going to be directly in the sun all day, but would still like to protect your skin, you should still periodically reapply lotion throughout the day.