From sunlight streaming through your window to the neon flashing lights that grab your attention at the mall — light is everywhere we turn. From dawn til dusk, we are bathed in both natural and artificial light. But what are the health impacts of natural vs. artificial light, and how might they affect you?
Light is an energy form that we use to perceive our surroundings. Sunlight is our primary source of light. We could not see, plants could not grow, and life on Earth would cease to exist without it.
Spending time outside surrounded by light is good for our mental and physical health.
Spending too much time in front of blue light emitting technology, especially at night, can be detrimental to our eye health, sleep cycle, and even mood regulation.
Try to spend at least one hour outside every day to maximize the benefits of surrounding light.
In celebration of Earth Day 2023, let’s explore the power of light and the ways in which it brings life to our beautiful planet.
Why we need light
Light is a form of energy that enables us to see. It initiates photosynthesis, which is a building block for life — every plant we eat uses the light to grow. Light warms the earth and drives the seasons that we experience. It also affects every human being in a profound way.
In order for our circadian rhythm to function properly (the rhythm that guides our sleep and wake cycles), we need light. Our bodies use the light as a signal to wake up, and to indicate when to wind down for the day.
Getting an adequate amount of light is critical to our well-being. The light levels we receive through the day can influence:
If you’ve ever suffered from jet-lag, you know first hand how groggy and foggy you can feel when your circadian rhythm is out of sync.
How is light measured?
Light is measured in lux. Sunlight typically omits anywhere from 50,000 lux to 100,000 lux. A regular house light bulb is pale in comparison, coming in at a measly 250 to 500 lux. So you can see why it’s so much more powerful to get outside and experience surrounding light for at least an hour a day.
Natural vs. artificial light
While there is light outside for most of the day, we are also bombarded with different types of artificial lights from inside. We have neon flashing lights enticing us to buy certain products, supermarket strip lighting, and our regular house lights. But how do these different types of light actually affect us?
Natural light – the light that surrounds us
Surrounding light is the type of light you experience when you are outside under the sun. Your whole body, from head to toe, is being bathed in light, even when the sun is behind the clouds. Because we are completely enveloped in light, we are able to absorb more of its benefits.
Healthcare professionals recommend at least one hour a day spent in surrounding light to reap the benefits, which include:
- Boosting vitamin D. Sunlight on the skin boosts the body's vitamin D storage, a crucial nutrient for bone health, immunity, and disease prevention. You can absorb vitamin D indoors through windows and outdoors directly onto your skin. Make sure to wear adequate SPF protection if you are going to be out in direct sunlight.
- Lessens symptoms of seasonal depression. Being outside and getting plenty of surrounding light can help beat those seasonal blues. Even winter sun is mood enhancing, so make sure to wrap up and get your face in the light, even on the greyer days.
- Good for eye health. Natural light has been shown to improve the function of the chemical dopamine in your retina. Dopamine in the retina acts differently to dopamine in the brain and is a critical component in eye health.
- Better sleep. Half an hour of natural light in the morning has been shown to have a positive effect on sleep quality during the night. Artificial light exposure for the same time doesn’t have that effect.
Artificial light – the fluorescent lighting
There are probably times when you’ve been unable to escape the harsh glare of fluorescent lights. Whether you are in the office, at school, or at the supermarket — they are everywhere. While some people remain relatively unaffected, there are those that are extremely sensitive to fluorescent light. Prolonged exposure in sensitive individuals can induce:
- Lightheadedness, vertigo or dizziness
- Headaches or migraines
- Eye pain or inflammation
- Blurred or impaired vision
- Difficulty reading or focusing
- Eye strain
- Shortness of breath
- Feelings of depression
- Disrupted sleep
The role of natural vs. artificial light in sleep
During the day, the more light we can get, the better. We want to be taking in light to inform our bodies that it’s time to be up, out and vibrant in life. However, at night the less lux we experience, the deeper our resting time and quality of sleep will be.
This is where the natural vs. artificial light debate really heats up.
The effects of artificial blue light
Sunlight gives off all the blue light we need for the day to help with alertness, sleep, metabolism regulation, memory, and cognition. It’s when we use blue light emitting technology at night that the issues arise.
TVs, phones, tablets, computers and other devices emit blue light. While this light isn’t harmful in healthy doses during the day from the sun, at night it can cause significant disruptions to our circadian rhythm — disrupting sleep, melatonin production, and can even induce insomnia.
Here are the common sources of blue light:
- Fluorescent lights
- Light-emitting diodes (LEDs)
- Smartphones and tablets
Over the last decade, there has been a wealth of research delving into the effects of using blue light-emitting technology at night. And the conclusions are clear, if you want to maintain a healthy sleep cycle, switch off your tech at least an hour before bed. Also, make sure your bedroom doesn’t have any LEDs left on during the night.
During the day, you can also limit the blue light by taking regular breaks from computer, TV, and phone screens. You can lessen the effects of eye strain by looking up from your screen every 20 minutes and looking at something at least 20 feet away for 20 seconds. This is known as the 20-20-20 rule.
Get more natural light on Earth Day 2023 and beyond
There’s no question that natural light is better for us than artificial light. It’s what enables life to form and seasons to emerge across the planet. If you want to reap the benefits of natural light, here are some of our favorite tips to help you get out into that health-giving surrounding light:
- Take a walk on your lunch break. Even the winter sun will benefit you more than your office lighting can.
- Walk to work in the morning. Taking a walk to work will get you out in the surrounding light will enable you to absorb more benefits. You’ll likely feel more alert and ready for your day when you arrive at your desk.
- Work outside. If you are able to, take your laptop to a park, or sit outside at a café while you do your admin. It’s a great way to habit stack, too — get those administrative tasks done while filling up your sunlight quota.
- Open a window. Get your desk as close to a window as possible. Make sure that you spend time with it open to let fresh air circulate and let the light touch your skin.
- Weekend hikes. Make the most of your days off and spend them out in nature. Hikes in the forest, and mountains and even taking your exercise outside with biophilia workouts are wonderful ways to get out in the surrounding light. You’ll also reap the added benefits of fresher air and be able to take in the beauty of the natural world.
Make the most of Earth Day 2023 with some quality time in the great outdoors, bathed in light and appreciating our stunning planet.
- Journal of Cosmetic Dermatology. Blue light protection, part I — effects of blue light on the skin.
- Aging and Mechanisms of Disease. Global rise of potential health hazards caused by blue light-induced circadian disruption in modern aging societies.
- Jama Cardiology. Beneficial effects of sunlight may account for the correlation between serum vitamin D levels and cardiovascular health.