Sunlight consists of two types of harmful rays — ultraviolet A (UVA) rays and ultraviolet B (UVB) rays. UVA rays (which pass through window glass) penetrate deeper into the dermis, the thickest layer of the skin. UVA rays can cause suppression of the immune system, which interferes with the immune system's ability to protect you against the development and spread of skin cancer. UVA exposure also is known to lead to signs of premature aging of the skin such as wrinkling and age spots.
The UVB rays are the sun's burning rays (which are blocked by window glass) and are the primary cause of sunburn. A good way to remember it is that UVA rays are the aging rays and UVB rays are the burning rays. Excessive exposure to both forms of UV rays can lead to the development of skin cancer.
The American Academy of Dermatology recommends that, regardless of skin type, a broad-spectrum (protects against UVA and UVB rays) sunscreen with a Sun Protection Factor (SPF) of at least 15 should be used year-round. Sunscreens are available in many forms including ointments, creams, gels, lotions, sprays and wax sticks. The type of sunscreen you choose is a matter of personal choice.
Ingredients that are found on sunscreen labels include:
- avobenzone (Parsol 1789)
- ecamsule (Mexoryl SX)
- menthyl anthranilate
- octyl methoxycinnamate
- octyl salicylate
- titanium dioxide
- zinc oxide
Because the active sunscreen ingredients will not usually block out the complete spectrum of UVA and UVB rays, sunscreens by themselves might not offer enough protection to prevent skin cancer and some of the other sun-related ailments. To thoroughly achieve sun protection, take as many of the following action steps as possible:
- Do Not Burn
- Avoid Sun Tanning and Tanning Beds
- Generously Apply Sunscreen
- Wear Protective Clothing
- Seek Shade
- Use Extra Caution Near Water, Snow, and Sand
- Watch for the UV Index
- Get Vitamin D Safely