The Science Behind the 20-20-20 Rule – Does It Work?

Knowledge workers often find themselves glued to their devices for hours on end. This increased screen time has raised concerns about eye health.

One simple, well-known solution to this problem is the 20-20-20 rule, a technique designed to protect and maintain eye health as life becomes ever-more digitized – but does it actually work?

In this article, we explore the science behind the 20-20-20 rule, explaining the extent to which it can be helpful.

Are Screens Bad for Our Eyes?

While screens themselves don’t cause permanent damage, extended use without breaks can lead to digital eye strain, also known as computer vision syndrome.

Symptoms include dry eyes, headaches, blurred vision, and neck or shoulder pain.

In work environments, where these symptoms most commonly occur, they can drastically impact wellness and productivity.

What Is the 20-20-20 Rule?

The 20-20-20 rule is a straightforward guideline for reducing eye strain caused by prolonged screen exposure. It encourages users to:

• Every 20 minutes,
• Look away from their screen for 20 seconds,
• Focusing on an object at least 20 feet away.

The Reasoning of 20-20-20: How Does It Help?

When you look at a screen, your eyes focus at a fixed distance, requiring the ciliary muscles to stay tense. Over time, this sustained muscle contraction can cause discomfort and fatigue – imagine how your arms would feel if you had to hold a push-up position or keep a weight elevated for hours.

By shifting your gaze to a distant object, these muscles get a chance to relax, reducing strain and preventing symptoms like blurred vision and headaches.

Moreover, screen use often reduces blink rate by up to 60%, leading to dry, irritated eyes. Taking a break encourages blinking and helps maintain moisture, which is essential for comfort and eye health.

Who Developed the 20-20-20 Rule?

The rule was developed by Dr. Jeff Anshel, an optometrist who observed a rise in vision-related complaints due to increased computer use. He advocated this rule as a practical, easy-to-implement ergonomic habit.

Anshel discussed the creation of the 20-20-20 rule in conversation with the Optometry Times, stating:

“In speaking to corporate workers, I needed a way to get them to take breaks while at the same time allowing them to accomplish their work. The general rule at the time was to take a 15-minute break every two hours. Yet most people with visual stress noticed problems earlier than two hours into their workdays.

“… I started with the ‘3B’ approach: blink, breathe, and break. Then the 20-20-20 rule came out of the ‘break’ recommendation.”

As for the methodological root of the rule, Dr. Anshel claims his thinking was based on research that showed taking shorter, more frequent breaks was beneficial in easing discomfort and reducing musculoskeletal disorders (MSD)s¹.

Using this information, he applied his optometry expertise and adapted it for ocular purposes.

Does the 20-20-20 Rule Really Work?

Survey studies have shown mixed results regarding the efficacy of the 20-20-20 rule.

A 2020 study found that patients with digital eye strain (DES) showed major improvements in tear film stability and dry eye symptoms after using the 20-20-20 rule over a 20-day period. However, core DES symptoms were only marginally improved.

In 2023, Datta et al. conducted a survey-based study in India to explore how often people practiced the 20/20/20 rule and whether following this guidance was linked to their reported symptoms. Findings again showed the 20-20-20 rule is effective at reducing headaches and burning sensations in the eyes – but that overall symptoms remained largely unchanged.

Yet another study – this one from 2022 – found that the 20-20-20 rule can help ease symptoms of DES, but is most effective when combined with other preventative measures.

The Takeaway From Research on the 20-20-20 Rule

The common thread among most studies is that the 20-20-20 rule is a reliable way of reducing some of the DES symptoms that limit wellbeing and productivity; however, it’s not a magic fix-all that completely protects screen users.

Moreover, research has shown that there is little significance to the number 20 when compared to other timings and distances. The important thing is that you’re taking regular breaks, blinking more, and focusing over different distances.

That said, “20-20-20” is a very catchy and well-known rule name, which helps people remember to apply it, so we recommend it as part of a healthy approach to screen use, nonetheless.

What matters is that you take a comprehensive approach to minimizing digital eye strain, which, again, should include regular breaks.

Beyond the Rule: Additional Eye Health Tips for Screen Users

While the 20-20-20 rule is useful, combining it with other ergonomic best practices can further enhance eye health:

• Adjust screen brightness to match ambient light and reduce glare.
• Maintain an arm’s length distance from your screen and position it slightly below eye level.
• Ensure proper room lighting to avoid excessive contrast between your screen and surroundings.
• Keep your workspace ergonomics optimized to reduce neck and shoulder strain, which can indirectly impact eye comfort.

Take Control of Your Eye Health with Healthy Working

Protecting your vision at work starts with smart habits like the 20-20-20 rule, but it shouldn’t stop there. Healthy Working, our ergonomics software, offers effective solutions to visual and physical risk factors associated with screen use and knowledge work.

Healthy Working can be customized to any workstation, combining self-assessments with tailored eLearning and a central management hub to identify and reduce ergonomic risk factors for all employees, including hybrid and remote workers.

Get a free trial of Healthy Working for up to 5% of your workforce.

Or contact Cardinus today to discuss your ergonomic requirements.