Coloring Your World—With Light

Put science to work in the light bulb aisle.

Posted Jan 21, 2018

We spend a lot more time pondering what colors to paint the walls of the rooms where we spend our days than we do choosing the colors of the lights that illuminate those spaces. When it’s winter where we live, as it is now in the Northern Hemisphere, that lack of attention can be particularly unfortunate.

During our winters, not as much light flows into our buildings through their windows as during our summers, so what we see inside is closely linked to the colors of the light bulbs we select. Light color varies from one sort of bulb to the next. Selecting the right light color—and bulb—makes it more likely what you’ve planned will actually happen in a space. In this article, we’ll be talking about the color of regular light bulbs, not the garish red/green/blue/etc. bulbs sold around Halloween and other holidays. 

We’ll be reviewing what cognitive science has to say about the implications of being in spaces lit by slightly warmer light or somewhat cooler light. The warmer light we’ll discuss ranges from around 2700 degrees Kelvin to about 4000 degrees Kelvin, which is where more clearly cooler light begins. Noticeably cool light is found at around 6500 degrees Kelvin, or so—but there’s no need to buy some sort of special meter to figure out the temperatures of light bulbs you own or that you’re considering buying—many bulb packages now indicate whether their contents provide warm or cool light.

Being in cool colored light is great if you're doing some sort of mental work that’s best done while alert; better cognitive performance, in that case, has been linked to being in places with cooler lights. Cooler light can be a good choice when you need to concentrate, but it’s a lousy option when you want to sleep. Cooler light can keep us awake, which is one of the reasons it’s a good idea to stop using electronic devices, such as iPads, long before bedtime—if your electronics don’t automatically adjust the color of light from your screen as you get ready to slumber.

Being in warm light makes us think and feel differently than that cooler light does. Under warm light, we’re generally more relaxed than we are under cool light and we get along better with others when we’re in a warmer glow—probably one of the reasons that fireplaces are so popular. Research also indicates that we think more creatively when we’re in warmer light. If you do different sorts of work in your home office, make sure some of the bulbs there produce cooler light and some warmer light. 

Different colors of light can help us feel calm or alert, or make it more likely that we’ll get along with others or think creatively, for example. Next time you’re standing in the light bulb aisle, use science to select the bulbs that’ll help you live the life you’ve planned.