Sunscreen versus Sunblock
Sunscreen versus sunblock.
“Who knew there was a difference?”, my client asked. I feel like she may not be the only one confused about the two, but before we break it down, let's talk about the difference between the UVA and UVB rays.
UVA Rays.
UVA rays are the main culprit for aging and wrinkling due to sun damage, also known as photoaging. These rays penetrate deeper into the skin-passing the epidermis, which is the skin we see today, and hitting the dermis, the skin that eventually exposes itself as we age. Although this terrified women who wanted to look young and beautiful forever (don't we all?), it wasn't a cause for concern for doctors-until recently. The more research being discovered, the more scientists realized UVA rays ARE a problem when it comes to cancers-i.e. basal cell and squamous cell carcinoma.
UVB Rays.
UVB rays are what we call the “ burning” rays. This damage we can see since it penetrates the epidermis-the skin’s outermost layer. These rays were always something we wanted to steer clear from since they can cause sunburn, skin cancer in the epidermis, hyperpigmentation, and aging.
Sunscreen.
Sunscreen is known for being a chemical form of protection. It absorbs UVA and UVB rays. Think of a screened in porch: although there is some protection, the outside elements can still be “absorbed” inside the porch. If you see words such as oxybenzone or octyl salicylate, you have sunscreen. They tend to be easier to rub in and are less visible when applying.
Sunblock.
Sunblock is a physical barrier that does exactly that- blocks the sun. Instead of absorbing the rays, it reflects them for ultimate protection. Common ingredients you will find in sunblock would be zinc oxide or titanium dioxide. Although we have come a long way from the thick, white stuff on the nose, zinc is a thicker consistency and can be more difficult to rub in.
So which is better? Well, coming from a freckled-faced Irish gal, I favor the sunblock. I still get a bit of a light tan, it's just a bit more subtle than most. Zinc oxide and titanium oxide are my best friends! A lot of formulas now have a mixture of the two. Whatever you choose, please be sure to buy broad spectrum SPF and reapply! According to the American Cancer Society, one should apply at least every two hours, but if you're swimming or sweating you should apply more frequently.
Sun protection should be used in all seasons. Whether your bathing in full sunlight, driving on a cloudy day, or running errands mid-winter, these rays are still in existence.
Sources:
American Cancer Society https://www.cancer.org/cancer/skin-cancer/prevention-and-early-detection.html
Ness Medical Life Sciences http://www.news-medical.net/news/2007/08/07/28543.aspx
Oncosec Medical http://oncosec.com/sunscreen-vs-sunblock-whats-the-difference/