Broad-Spectrum (full spectrum sunscreen) protects against both UVA and UVB radiation. In order for a sunscreen to be considered Broad-Spectrum protection, the UVA protection must be equal to the UVB protection.
What is the Difference between UVA and UVB Rays?
UVA RAYS
• Also known as Aging Rays
• Indirectly damage DNA
• They can affect cells deeper in the skin
• Contributes to 95% of the UV rays that reach the earth’s surface
• Weakens the skin’s collagen and elastin fibers
• Contributes to aging, wrinkles and sagging skin
• The main light used in tanning beds
UVB RAYS
• Shorter wavelengths that are more damaging to the skin and can damage the eyes
• Directly damage DNA
• Damage the outermost layer of the skin
• Contribute to Premature Aging
• Cause most skin cancers
• Overexposure can lead to sunburns
• Contributes to the body’s synthesis of vitamin D and other important minerals
What is Sunscreen?
The sun is the main source for two types of UV rays that are harmful to the skin. UVA rays seep deep into the skin, causing aging, wrinkles, and sagging skin. In contrast, UVB rays are shorter than UVA rays. Yet, they damage the outermost layer of the skin, causing sunburns and skin cancer. Sunscreen is designed to protect the skin by absorbing, disabling, and reflecting the rays.
What is SPF?
Sun Protector Factor measures the sunscreen's ability to protect your skin from UVB rays. The calculation is simple. It usually takes 10 minutes for your skin to start to burn without using sun protection. Let us assume that you use an SPF 30 before heading out for a morning jog. By using SPF 30, you are, in theory, protected from the sun for 300 minutes or 5 hours. It is vital to know that SPF only protects against UVB rays. It does not account for the UVA rays that cause aging, wrinkles, and sagging skin.
Calculation
SPF 30 X 10 MINUTES in the Sun = 300 MINUTES of Sun Protection without a Sunburn
300 MINUTES / 60 MINUTES = 5 HOURS of Sun Protection without a Sunburn