Our New Year’s resolutions often include ambitions to be more productive. As we continue working or studying from home, staying focused and energized can be quite a challenge! In this article, we explore an often overlooked element that is essential to our homes and can have a massive influence on how we feel and perform throughout the day: our lighting. Lighting is a particularly important concern if you live in the northern hemisphere. The winter months bring less daylight hours, which can make it more difficult to get appropriate exposure to sunlight and thus maintain a healthy circadian rhythm. In fact, that’s why many people experience seasonal affective disorder (SAD) and why light therapy is sometimes recommended as a treatment. But good lighting in the darker months is important for everyone to support optimal functioning, from mood to sleep to metabolism.
Read on for some tips on how to boost your productivity without putting extra strain on your already-overloaded brain.
Light Affects Critical Body Functions
Our bodies are naturally programmed to function on a cycle that matches the solar day. This cycle, known as the circadian rhythm, governs many aspects of our physiology, metabolism, and behavior. Our circadian rhythm is primarily synchronized by light. Daily, regularly-timed exposure to light helps us maintain a healthy and robust circadian rhythm; this process is called “entrainment.”
Ideally, our light patterns across the 24-hour day should mirror the sun — which means darkness at night, but also brightness in the day. Many of us know that it’s important to avoid bright light close to bedtime to avoid disrupting our circadian rhythms, especially the blue-white spectrum of cell phones and other screens. But what’s less well known is that it’s equally important to get exposure to the right light during the day to support your health, performance, and well-being.
Daytime light exposure can boost how you function and feel during the day, but its effects aren’t limited to that time period. It also helps to keep your circadian rhythm aligned, which ultimately helps you achieve restful and restorative sleep at night.
Bright, Cool Light for Energizing Days
When considering the lighting in your space, there are two key aspects of light to think about: illuminance and color temperature.
“Illuminance,” measured in lux, represents the amount of light reaching an area from a light source, or what we can think of as its “brightness.” Studies have shown high-illuminance lighting to positively impact productivity-related outcomes — including improved vitality, vigilance and attention sustenance, self-reported and physiological alertness, performance on cognitive tasks, and reduced sleepiness.
Meanwhile, the “temperature” of lighting indicates its color appearance. Like illuminance, a higher CCT — i.e., a cooler color, such as blue or white — has been linked to a range of improved productivity outcomes in adults, including better performance, improved ability to concentrate, reduced fatigue and sleepiness, and increased alertness and vitality.
These effects appear to hold true for younger people as well. For example, studies have found that when exposed to higher-CCT lighting, preschool-aged children showed greater improvement in executive function abilities (e.g., improved task switching accuracy); high schoolers showed greater improvement in cognitive processing speed and concentration; and university students experienced a greater reduction in melatonin, which could help combat morning drowsiness, as well as improved subjective perception of alertness, mood, and visual comfort.
Brighter intensity and cooler color temperature can be combined to help support performance. For example, one study of third- and tenth-graders compared students whose classrooms had bright, cool light, vs. students whose classrooms had conventional classroom lighting. Students in the bright, cold light group made 20.8% fewer errors of omission in a test measuring attention and demonstrated a 9.7% increase in reading speed. In a similar study of third-graders, students showed a 19% increase in oral reading fluency performance after exposure to brighter, cooler “focus” lighting compared to students exposed to normal lighting.
While focusing on your indoor lighting is key, don’t forget about the sun! Natural daylight can be around 100,000 lux, providing illuminance at levels that are difficult for indoor lighting to achieve. Finding a workspace near a window can give you access to sunlight and also to natural views, which have their own beneficial effects. One study – conducted by the Well Living Lab, founded as a Delos and Mayo Clinic collaboration – compared outcomes when people worked with no daylight or view and when they worked near windows equipped with shading systems that provided access to daylight and views while minimizing glare. The workers with window access showed improved cognitive performance and satisfaction, while the shading helped reduce the potential adverse effects of glare from the daylight.
Lighting Tips to Boost Performance:
- Maximize your daylight exposure. If you can, position yourself near a window to work, and keep your shades open. Try to take walking breaks outside, especially when the sun is out (bonus: short breaks can be great for productivity, too!). If possible, try doing some of your work outdoors.
- Adjust your indoor lighting settings. During the daytime, make sure your work area is well-lit: with the lighting set to be bright and cool if possible. Using tunable lighting can help you control brightness and CCT; check out our recent article 12 Healthy Home Tips for the New Year for more guidance on how to make your lighting work for you.
- Tweak your lighting based on who’s using it. If you have people of different ages in your household, keep in mind that circadian sensitivity decreases with age – adults may need brighter/cooler light to achieve the same alerting effect, compared to children and adolescents.
- Tune it down at night. While bright light is important for us during the day, the opposite is true at night: If you’re working in the evening or night, make sure to start dimming the light intensity and making the CCT warmer when the sun sets.
Edited by: Bing Bing Guo, MPH, Regina Vaicekonyte, MS and Radhika Singh