While there is no need to wear sunscreen under your UPF 50 long sleeve sun shirt, you may want to consider it for other articles of clothing. UV radiation can penetrate clothing, but it all depends exactly how much. This might seem like a ridiculous idea, but it’s actually something more people should be considering. Below are some situations when you should and shouldn’t consider applying sunscreen underneath your clothing:
If Your Shirt Has a UPF Rating Listed:
Should you wear sunscreen underneath? No need
A long sleeve sun shirt with a UPF 50 rating means you are receiving the equivalent protection of a sunscreen with an SPF 50 rating. So in this situation – no, it’s not necessary to also wear sunscreen underneath your clothing. Oftentimes people choose to buy a sun shirt because it allows them to go about their day without having to apply sunscreen. It always keeps you covered, never needs reapplication, and is also a very comfortable option. If you already have proper UPF gear, no need to lather up with sunscreen as well (except for any exposed areas like the hands and face).
No UPF Rating Listed, But You Think Your Shirt Is Sun Protective:
Should you wear sunscreen underneath? It depends
Without proper lab testing, it’s very difficult to determine exactly how much protection you are getting. If you can hold a fabric up to a light and absolutely no light can get through, it’s likely that it is providing superb protection. However, this is not always the case. Even UPF 50 long sleeve sun shirts allow visible light through, but it still provides excellent UPF protection.