Does inadequate illumination cause eye strain?

From the Guidelines

Inappropriate darkness can indeed strain the eyes, as it forces them to work harder to focus, leading to eye fatigue and strain. This is because, in low light conditions, the pupils dilate to gather more visual information, and the eye muscles must work overtime to maintain focus 1. Symptoms of eye strain from poor lighting include headaches, blurred vision, dry eyes, and difficulty concentrating.

To prevent eye strain, it is essential to ensure adequate lighting for activities. For reading or doing detailed work, using a desk lamp that provides direct, non-glaring light is recommended. For computer use, the ambient room lighting should be about half as bright as typical office lighting. Additionally, taking regular breaks using the 20-20-20 rule can help alleviate eye strain: every 20 minutes, look at something 20 feet away for 20 seconds 1.

Some key points to consider when optimizing lighting to prevent eye strain include:

• Using soft light, which is recommended, but also exposing individuals to natural light, as it has been shown to be beneficial for recovery times and decreasing delirium 1
• Utilizing light-colored walls with a matte sheen and light flooring with a low-glare finish to optimize lighting and reduce glare 1
• Increasing the level of lighting to improve acuity, as older adults require three to four times as much light as young adults for visual clarity 1
• Combining ambient and spot lighting to achieve optimal results 1

It is crucial to note that while blue light emitted from computer screens has been hypothesized to cause eye strain, the current evidence is contentious, and there is a lack of supporting evidence and a compelling biological mechanism through which blue light might cause eye strain directly 1. If an individual experiences persistent eye strain despite proper lighting, it is recommended to consult an eye care professional, as it could indicate an underlying vision problem requiring correction.

From the Research

Inappropriate Darkness and Eye Strain

• Inappropriate darkness may strain the eyes, but there is limited research directly addressing this topic.
• However, studies have investigated the effects of blue light filtering lenses on eye strain, which may be relevant to the discussion of darkness and eye strain.

Blue Light Filtering Lenses and Eye Strain

• A study published in 2023 2 found that blue-light filtering spectacle lenses may not attenuate symptoms of eye strain with computer use, compared to non-blue-light filtering lenses.
• Another study from 2021 3 reported that blue-blocking lenses did not alter signs or symptoms of eye strain with computer use relative to standard clear lenses.
• A 2020 study 4 also found no significant difference in symptoms of digital eye strain between blue-blocking filters and a no-filter lens.
• However, a pilot study from 2020 5 suggested that blue light filtering lenses may ameliorate computer vision syndrome symptoms in radiology residents.

Limitations and Future Research

• The current evidence on blue light filtering lenses and eye strain is limited, and more research is needed to fully understand their effects.
• A systematic review from 2021 6 highlighted the lack of consistent evidence for the clinical efficacy of blue light blocking lenses in preventing ocular disorders, including eye fatigue and sleep quality issues.
• Further studies with larger sample sizes and diverse populations are required to determine the potential benefits and limitations of blue light filtering lenses and their impact on eye strain.