Not all fabrics offer the same level of sun protection. While cotton is comfortable and breathable, it tends to allow more UV radiation to pass through, especially when it's thin or light-colored. In contrast, technical fabrics designed with UV protection help block the sun's rays more effectively, keeping your skin better protected during extended sun exposure. Factors such as fiber type, weave, and color directly influence the level of protection. Therefore, choosing a UV-protective shirt can make all the difference when spending time in the sun.