UV Rays

Sunlight emits two different types of rays; ultraviolet A (UVA) which is responsible for skin damage and premature aging (wrinkles, age spots, etc.) and penetrates the deeper dermal layers of the skin; and ultraviolet B (UVB) which is responsible for sunburns. Too much exposure to either UVA or UVB can cause skin cancer.

UVA Rays
• Penetrates deep into the dermis, the skin’s thickest layer.
• Responsible for pigmentation changes and photodamage: dryness, uneven pigmentation, inflammation, fine wrinkles.
• Same strength all year round during daylight hours, even in winter and on cloudy days.
Can penetrate glass.
• UVA exposure has been linked to the development of basal and squamous cell cancers.
• Damage from UVA rays are cumulative, and generally, the effects will not appear until years after exposure.

UVB Rays
• Only penetrates the skin’s surface.
• Cause of initial appearance of sunburn.
• Strongest during the spring and summer from 10 am to 4 pm, and on sunny days.
• The underlying damage accumulates, resulting in basal and squamous cell cancers.
• Exposure to UVB is responsible for premature aging to the skin.

For that reason you will want to have a sunscreen that is labelled broad-spectrum that protects from both rays. SPF stands for sun protection factor and measures how well the sunscreen protects against UVB rays. UVA protection isn’t actually rated. Experts recommend using an SPF with at least 30. Sunscreen greater than 50, provide only a minimal increase in UV protection. Higher number SPFs last the same amount of time as lower number SPFs.