To decode the back of your sunscreen bottle you no longer need a PhD in Chemistry! Read the following explanations and become an expert.

• SPF: Sun Protection Factor. This refers to the protection the product provides against UVB rays. A sunscreen with an SPF of 30 allows 1/30 of UVB rays to pass through to the skin.
• UVR: Ultraviolet rays of the sun, which are divided into UVA, UVB and UVC depending on the wavelength.
• UVA Rays: The ultraviolet rays which are responsible for aging your skin because they penetrate to the very bottom of your skin layers and destroy the cells that produce elastin and collagen. UVA rays are present year round.
• UVB Rays: The ultraviolet rays responsible for sunburns. These rays do not penetrate to the bottom of the skin layers but they do prompt your skin to produce melanin, the stuff that makes you tan, and are strongest during the summer months and between 10am and 2pm.
• PA & PPD: These two indicators refer to the protection a sunscreen has against UVA rays. PA uses crosses while PPD uses numbers.

Low UVA protection: PA+ = PPD 2-4

Medium UVA protection: PA++ = PPD 4-8

Ideal UVA protection: PA+++ = PPD 8 and above

Wide spectrum sunscreens protect against both UVB and UVA rays.