What is the Difference, and Which One Is Better?
The main difference in sunscreen and sunblock lies is the way they protect the skin from UV rays. Sunblock is so named because it literally blocks UV rays by forming a physical shield, while a sunscreen contains chemicals that absorb UV rays before your skin can.
Generally, sunscreens are designed to protect against UVA rays, which promote skin damage. Sunblocks, however, are formulated to stop the damage caused by UVB rays, the kind that cause a sunburn. Many sunscreens and sunblocks will help to prevent wrinkles and sunburn.
Both types of sun protection have their pros and cons.
Sunscreen, which contains organic chemical compounds such as octyl methoxycinnamate, octyl salicylate, and ecamsule, relies on a chemical reaction to absorb UV light and convert it into heat, which is then released from the skin.
On the other hand, sunblock contains mineral ingredients like titanium dioxide or zinc oxide that physically block UV rays.
Sunscreen and sunblock also have different application methods. Because sunscreen only works when it’s absorbed by the skin, it needs to be rubbed in and disappears completely. But you can simply slather sunblock on, since it acts as a physical barrier. You do have to apply sunblock evenly, it normally leaves a white cast on the skin.
Sunblock have the edge because it doesn’t have any chemical ingredients that can cause irritation. Works best for people with sensitive skin or skin conditions, some of the ingredients in chemical sunscreen might cause irritation or an allergic reaction.
What is a SPF
The SPF on sunscreen stands for sun protection factor, a relative measurement for the amount of time the sunscreen will protect you from ultraviolet (UV) rays.
Normally begins to burn after 10 minutes in full sun without any protection. A 30 SPF sunscreen would provide 30 times the protection of no sunscreen."
That means 30 times longer before you start to burn. That means 30 times longer before you start to burn, or in this case, 300 minutes. if swimming or sweating a lot, it is recommended to apply hourly.
What is Full/Broad Spectrum SunScreen?
The official FDA definition of Broad Spectrum Sunscreen is, "The sunscreen can protect you from the sun’s harmful ultraviolet A (UVA) and ultraviolet B (UVB) rays.” In theory, it means the sunscreen covers the complete UV spectrum and protects both the skin's surface and deeper skin tissues against UV rays from the sun.
UVA rays damage deeper tissues.
A broad spectrum sunscreen technically means it should defend against both UVB and UVA rays. It’s important to note a product’s SPF relates ONLY to UVB rays, those affecting the surface. It has nothing to do with effectiveness against UVA rays, those which damage deeper tissues.
Both UVA and UVB rays damage the skin’s DNA so genetic mutations occur, which leads to premature aging and/or skin cancer.
According to the CDC
Skin cancer is the most common cancer in the United States. Some people are at higher risk of skin cancer than others, but anyone can get it. The most preventable cause of skin cancer is overexposure to ultraviolet (UV) light, either from the sun or from artificial sources like tanning beds. Click for more info
In a Nutshell
Protect your skin from the sun! Wear a cute hat, sit under an umbrella and wear a sun protective lotion!
SunBlock (mineral) protects from UVB rays reflects the sun's ray, gives full protection and should be used if you have sensitive skin or concerned about skin cancer. Can leave a white coat to the skin.
SunScreen (chemical) protects from UVA rays, you will have to be applied often, it absorbs the sun rays and will give you a suntan or sunburn.
Broad/Full Spectrum are designed to protect the skin from both UVA and UVB rays.