Also, many of the reading lights on the market are daylight temperature, as the color provides great contrast between black type on white or off-white paper, making it easier on the eyes to read.” Kukuk also says that daylight bulbs are popular in bathrooms, because they make it easier for women to see what their makeup will look like outdoors.
Some studies suggest that light in the blue portions of the spectrum can help you wake up in the morning, making cool white and daylight bulbs especially suitable for bedrooms. “This ‘upper high-Kelvin’ light can trigger a photoreceptor called melanopsin that helps set your body’s daily cycles and can keep you more attentive and alert so, for example, you can read and study longer, comprehend better, and make fewer errors,” says Michael Gottsacker, former director of marketing for Verilux, which sells light-therapy products.