The terms sunscreen and sunblock are often used interchangeably.
To a large extent, this is fair considering that both are topical lotions that protect the skin from the sun’s harmful ultraviolet radiation (UV).
But, there is a significant difference between sunscreen and sunblock in terms of how these lotions work.
Sunscreen: A Chemical Formula
The term “sunscreen” generally refers to chemical sun lotion compositions. Sunscreens contain ingredients like oxybenzone, avobenzone, and octinoxate, which rely on a chemical reaction to absorb UV light, convert it to heat, and then release that energy from the skin, preventing the UV from damaging your body.
These chemical sunscreens absorb easily into the skin and don’t leave any kind of residue or caste behind (except for maybe a bit of an oily feeling).
Sunblock: A Physical Formula
The term “sunblock” generally refers to physical sun lotion compositions, which contain minerals like zinc oxide or titanium dioxide.
Sunblock doesn’t absorb into the skin – instead, it sits on the top of the skin to create a physical barrier that reflects sun and UV rays away from the skin. This is why these types of topical lotions are referred to as sun blocks – they block your skin from the sun.
Most sunscreens and sunblocks protect against both UVA and UVB rays – look for the “broad spectrum” label to be sure.
Sunblock vs Sunscreen: Which is Better?
There’s no hard and fast rule about sunscreen being preferable to sunblock, or vice versa. They both have their benefits and drawbacks, so it’s all about your preference.
Keep in mind that:
- Sunblock provides a physical barrier on the skin. This means it won’t absorb into your skin, and will leave a white cast that can make you look a bit ghostly (but provides great protection)
- Sunscreen doesn’t leave a cast, since it absorbs into your skin. Some people don’t like the idea of chemicals being absorbed into the skin and consider the nanoparticles in chemical sunscreens unsafe, but there hasn’t been any research to really suggest that there is any danger with chemical sunscreens.
- Since sunscreen absorbs into the skin, some users experience skin irritation or allergic reactions. Some sunscreens can cause itching, rashes, and other irritation due to how they interact with the skin as they are absorbed. This isn’t often an issue for sunblocks since they do not absorb into the skin.
- Choose either, but definitely choose one – while there may be some drawbacks or uncertainties around specific types of sunscreen, any sunscreen is safer than none!
So remember: sunblock and sunscreen both protect your skin from the sun, but are different in how they work. Sunblocks are physical lotions and don’t absorb into the skin, while sunscreen is chemical and absorbs into the skin.
Be sure to check out our full guide comparing chemical vs mineral sunscreen for a more comprehensive, in-depth dive examining these two types of sun protection skin applications!
Do you prefer sunblock or sunscreen? Let us know in the comments!