How Good Lighting Impacts Mental Health

At Blind Ambitions, we sell window coverings. We’re proud of those coverings and the effort we put into helping you choose the right design and fabric for every window in your home.

We also care about how our window coverings influence your well-being. Light plays an important role in our mood and sleep; our window coverings affect how light enters your home. We hope that what we’ve learned about light  over the years helps you understand how good lighting can improve your mental health: 

Understanding The Science: Light And The Brain

The relationship between light and the brain is complex and multifaceted; as we’ll discuss throughout this article, how light and the brain interact is affected by:

• The type of light you see

• When you see that light

• Where you see that light

• How long you see that light for

Light has many effects on both mental and physical health; several different mechanisms may influence the effect of light on health. Some of the biggest effects of light seem to relate to sleep; light at the wrong time can alter circadian rhythms and sleep, while light at the right time can improve sleep.

Exposure to light can also decrease melatonin production; melatonin is a key hormone in sleep regulation. Higher levels of melatonin signal your body to prepare for sleep; exposure to light at night can interfere with this process, while exposure to light during the day can help promote wakefulness.  

Serotonin production, on the other hand, seems to be increased by exposure to sunlight, which may boost mood and focus. 

These are just a few of the many things that influence how light can affect thinking and mood. Before we dive into the science of light and the brain, we should also mention something we’re not going to talk about at great length: Aesthetics.

Aesthetics can influence your mood. You need light to see. As a result, light has a profound impact on visual aesthetics. When we visit your home or business to install window coverings, we will consider how light flowing through the room will impact the aesthetics of the room. We cannot talk about aesthetics at great length here, however, because they’re subjective. 

Natural Light & Its Benefits

The benefits of natural light are well-founded: 

• A study published in 2021 found that time spent outdoors improved mood and sleep quality. 

• A study published in 2014 found that workers who were exposed to daylight reported greater well-being and greater overall sleep quality than those in windowless environments.

• A study published in 2021 found that access to daylight at home improves circadian alignment, sleep, and mental health in healthy adults.

These studies (and many others) suggest that natural light exposure may have a profound impact on mental health.

Artificial Light & Its Role

Artificial light plays an essential role in our modern infrastructure. Streetlights make it easier for pedestrians and drivers to see while they’re out at night. Indoor lighting helps us continue with daily activities well after sundown. Screens are constant companions for many of us, emitting light even as we fall asleep.

Artificial lighting is crucial in modern society; unfortunately, there is evidence that exposure to artificial light at night (ALAN) can have negative impacts on health and well-being:

• A 2022 study found that ambient nighttime light exposure is a risk factor for adverse health outcomes.

• A 2014 study found that evening use of light-emitting eReaders negatively affects sleep.

• A 2020 study found that ALAN exposure is associated with mood and anxiety disorders in adolescents.

• A 2024 study found that both indoor and outdoor ALAN exposure are associated with increased risk of depression.

The Mental Health Connection

Exposure to daylight can improve mental health; exposure to artificial light at night (ALAN) is associated with higher risks of depression in adults, and higher risks of mood and anxiety disorders in adolescents. A practical takeaway can be drawn from these facts: Increased daytime light exposure and reduced nighttime light exposure may improve mental health. 

Lighting & Depression

Harvard Health released an article in 2022 describing how light therapy can help with seasonal affective disorder (SAD), an issue we understand well here in Winnipeg, where daylight exposure during the winter can be incredibly low. The article also describes how daytime light may help with other depressive disorders.

We already know that ALAN exposure may increase the risk of depression, thanks to the study linked earlier. We also know that daytime light exposure through windows may improve sleep quality. A 2022 study found that poor sleep quality is associated with depressive symptoms; it is possible, then, that daytime light exposure through windows may decrease the risk of depression by improving sleep quality.

Lighting & Anxiety

We’ve already explored how ALAN may increase the risk of anxiety in adolescents. Another recent study found that nighttime light exposure can increase the risk of anxiety. 

This brings us to the same conclusion as with depression: More natural daylight and less ALAN exposure may both help improve anxiety. 

Sleep & Mood Regulation

Sleep and mood are related; beyond what we’ve just explored, there’s evidence that poor sleep or inadequate sleep can cause stress, while high-quality sleep can improve well-being.

Many of the studies we have already explored also show a relationship between daylight exposure and improved sleep quality, and ALAN exposure and decreased sleep quality. 

One possible conclusion from the research is this: Reducing ALAN exposure and increasing daylight exposure may improve mood by virtue of improving sleep quality. 

Practical Tips For Better Lighting

Optimizing Natural Light At Home

Many of the studies we’ve examined link direct daylight to improved mental health; even if you have massive bay windows and skylights, there’s no replacement for going outside.

With that being said, there is also some evidence that environments with diffused daylight, like indirect sunlight, may also boost mental health. 

Fortunately, there are several strategies we can use to increase the amount of natural light you get at home (or at work).

Here are a few tips for maximizing natural light:

• Place mirrors to reflect the natural light coming through your windows throughout the room.

• Use light, warm coloured paints and furniture; darker colours absorb light. Glossy or satin finishes are more reflective, further enhancing natural light.

• Ensure that there are no obstructions blocking light from coming through your windows.

• Consider installing skylights for even more natural lighting.

• Use sheer or light-filtering window coverings if you want increased privacy without sacrificing as much natural light.

Reducing Exposure To Artificial Light At Night (ALAN)

As we’ve explored, exposure to ALAN is a risk factor for adverse mental health conditions like anxiety and depression. 

Fortunately, reducing exposure is possible. One way to do this is by using blackout or room-darkening solutions to limit the flow of light from streetlights and other outdoor lights into your windows. We always tell our clients that there is no such thing as a true blackout curtain - light flows wherever it can - but room-darkening window coverings can still reduce exposure to ALAN. 

To improve sleep, try to do the following an hour or two before bed:

• Turn off as many lights as you can.

• Stop using electronic screens.

• Close window coverings (even if they are not room-darkening).

The cold turkey technique doesn’t work for everyone; a lot of us are very used to using screens and lights before we sleep. Fortunately, there’s some evidence that focusing on contrast between day and nighttime lighting may also help, so your phone is not the only angle you need to consider. 

Creating A Healthy Lighting Routine

Healthy lighting routines are based on your circadian rhythm. Studies (including two included in one narrative review of the literature, which we will link to in Additional Resources) will often state that early morning light is best. This can cause some confusion, as “early morning” means “early morning relative to your own circadian rhythm.” 

Wake up naturally at 6? Direct sunlight at 7 in the morning might feel fantastic. Wake up naturally at 10? Direct daylight at 7 in the morning might feel terrible.

With that in mind, here’s what a healthy lighting routine might look like:

• Wake up.

• Get direct sunlight within an hour of waking up (if direct sunlight is unavailable, a light therapy box may help).

• Spend the day in bright light (indoor or outdoor); ideally, bright lights that emulate daylight should be used.

• As the day turns to evening, begin to dim your lights. Switch from blue light to warmer red, orange, and yellow hues if possible.

• Begin to turn off lights about an hour before bed.

• Sleep.

We should note that this is not medical advice; you should talk to your doctor, a sleep specialist, and other members of your medical team if you are having trouble sleeping and want to know how a lighting routine could improve your sleep. Light therapy boxes, for example, can have adverse effects on people with some mental health conditions. 

Common Myths About Light And Mental Health

• Blue light is bad for you. Blue light and other bright lights are not bad for you; they are a crucial signal to your body to stop producing melatonin. Less melatonin can mean more wakefulness in the day; it’s just best to avoid blue light at night.

• Blue light will ruin your sleep. Blue light won’t ruin your sleep; continuous light exposure throughout the night and before bedtime, however, may disrupt it. The colour of your light is only one factor; reducing the amount of light may be more important.

• More light will always improve your mood. Consistent light throughout the day and dimming light throughout the night seems to be best; non-stop light may not be ideal. One study we read indicated that there may actually be an optimal amount of time spent outside in daylight to reduce your risk of depression - around 1.5 hours of exposure. 

Additional Resources

Effects of light on human circadian rhythms, sleep and mood: This narrative review of the literature was our primary source for this article; a worthwhile read for anyone looking to understand the effects of light on mental health.

Association of time spent in outdoor light and genetic risk with the incidence of depression: The study estimated the optimal amount of time outside to reduce depression at around 1.5 hours of exposure.

What Color Light Helps You Sleep?: An article by The Sleep Foundation that provides an overview of which colour light to use throughout the day and how it might affect your sleep.