Staring at a computer for hours on end, only to take a break by switching to stare at your phone, is hardly the healthiest way to spend your day. Unfortunately, with online work and classes to study for, it’s the reality for many—if not all—students.

Since the initial COVID-19 outbreak in March, most of us have been trying our best to stay healthy despite the current circumstances. A number of students—myself included—have turned to blue light glasses as they become concerned with maintaining their eye health during prolonged periods of screen time.

What is blue light?

Sunlight is made up an array of coloured light: red, orange, yellow, green, blue, indigo, and violet. When we look at digital screens, we expose ourselves to large amounts of blue light. This type of exposure isn’t as dangerous as the type of radiation we get from X-rays or UV light, but studies have suggested too much exposure can lead to digital eye strain and retina damage. Using devices that emit blue light can also affect your sleep schedule, as it works to suppress the sleep-promoting hormone known as melatonin.

What are blue light glasses?

Blue-light glasses, also known as blue-blocking lenses, work to reduce the amplitude of short-wavelength light. These glasses are marketed to help with eye fatigue or eye strain by blocking blue light, also known as high energy visible (HEV) light, from any device emitting it. In addition to manufacturers’ claims of alleviating of eye strain, blue light glasses are also said to improve sleep.

Do they work?

For a starting price of about $15 on Amazon, investing in blue light glasses seems like a worthwhile purchase. But will they improve your health?

The short answer is that we don’t know. Research regarding the impact of blue light on our eyes, as well as the effectiveness of blue-light blocking glasses, has been generally inconclusive.

A study published in the scientific journal PLOS ONE suggested chronic exposure to blue light may contribute to retinal photodamage. The study also mentions that blue light glasses could alleviate the impact this light has on retinal photosensitive cells, which may help prevent eye damage. Another study, published in Ophthalmic & Physiological Optics, concluded there’s a “lack of high-quality evidence” to support the alleged efficacy behind blue-light glasses in alleviating eye strain, improving sleep quality, and preventing retina damage.

Personally, I own a pair of blue light glasses, and I love them—I’ve been experiencing less eye strain since I started spending a significant amount of time on my computer this fall. However, I’ve also been deliberately regulating my time with breaks from the screen. It’s hard to know whether my blue-light glasses actually work, or if I just like to think they do.

If you’re willing to invest some money in a pair of blue light glasses, you may find they help your online studies—but it’s not guaranteed. If a pair is outside of your budget and you’re looking for other ways to ease eye strain, try the “20-20-20 rule”: every 20 minutes spent on a screen, take a break to look at an object 20 feet away for at least 20 seconds. If you’re concerned with blue light exposure, most computers and phones allow you to reduce the number of hours the device emits this type of light.

Spending days glued to your computer can be hard on your wellbeing, so make sure you’re taking care of your health—and consider giving blue light glasses a shot.