Understanding Blue Light: Why It’s Important to Reduce Exposure and How to Do It

What is Blue Light?

Blue light is a type of high-energy visible (HEV) light that is emitted by the sun, as well as by most of the digital screens we use every day—like our phones, tablets, computers, and even TVs. It has a shorter wavelength and higher energy than other colors of light, which is why it can be so intense on our eyes.

In small doses, blue light is actually beneficial—it helps regulate our sleep-wake cycle (also called the circadian rhythm) and boosts alertness during the day. Natural blue light from the sun plays an important role in keeping us awake and focused.

However, the problem comes when we're exposed to too much blue light—especially from artificial sources like screens. When we’re constantly looking at screens, especially at night, it can mess with our sleep and even cause eye strain. Our eyes don’t have a natural filter for blue light, so the more we’re exposed, the more it can affect our health.

Why It's Best to Avoid Blue Light (and When)

While blue light has its benefits during the day—helping you feel alert and focused—exposure at the wrong times can interfere with your health in several ways.

Disruption of Sleep and Circadian Rhythm
One of the most important reasons to limit blue light exposure, especially at night, is its impact on your circadian rhythm, or your internal body clock. When you’re exposed to blue light—particularly from screens—your body can get confused, thinking it’s still daytime. This can interfere with your production of melatonin, the hormone responsible for helping you fall asleep.

Melatonin usually begins to rise in the evening to prepare your body for rest, but blue light exposure suppresses its production. As a result, you might have trouble falling asleep or staying asleep, leaving you feeling groggy and fatigued the next day. For me, I noticed that if I was scrolling through my phone right before bed, I’d often struggle to wind down or fall asleep.

Impact on Mood and Mental Health
Chronic exposure to blue light late at night may also affect your mood. It has been linked to increased levels of stress and anxiety, likely because of its impact on sleep. Poor sleep, in turn, can affect mental clarity, emotional regulation, and overall well-being.

When to Avoid Blue Light
To protect your sleep and circadian rhythm, it’s best to avoid blue light exposure about 1–2 hours before bed. That means putting down your phone, closing your laptop, and turning off bright overhead lights. The evening is the most crucial time to avoid this type of light because it’s when your body naturally starts preparing for rest. Instead, try switching to warmer, dimmer lighting and picking up a book or engaging in a relaxing evening routine.

Hormonal Effects of Blue Light
As mentioned, blue light disrupts melatonin production, which is the most well-known hormone affected. But melatonin isn’t the only hormone that can be influenced. Research has shown that blue light exposure can also interfere with cortisol levels (your stress hormone). Disruptions in cortisol, especially if it spikes late at night due to blue light exposure, can keep you alert and make it harder to unwind.

Simple Things You Can Do to Eliminate Blue Light

Reducing blue light exposure from your devices can be easier than you think! Here are some simple tips to help minimize its impact:

• Use Blue Light Filters: Most smartphones, tablets, and computers now have built-in blue light filter settings. Make sure to enable these features, especially during evening hours. For most devices, this can be found under settings<display & brightness<night shift mode.

• Adjust Screen Brightness: Dimming your screen brightness can help reduce overall light exposure. Don't keep your devices on maximum brightness.

• Limit Screen Time Before Bed: Try to create a technology-free routine at least an hour before bedtime. Reading a book or engaging in calming activities can help your mind wind down.

• Wear Blue Light Blocking Glasses: If you spend a lot of time on screens, consider investing in a pair of blue light-blocking glasses. These can filter out harmful blue light when you're engaged in lengthy viewing sessions.

• Utilize Apps and Software: There are many apps available that adjust your screen's color temperature according to the time of day, reducing blue light exposure in the evening.

• Blue light-blocking screen protectors: Consider adding blue light-filtering screen covers to your cell phone, tablet, and computer.

By understanding what blue light is and taking steps to reduce it in your daily life, you can improve your sleep quality and overall comfort while using your devices. Give these changes a try, and you might just notice a difference!