The impact of blue light on sleep: science versus marketing

Blue-light-filtering glasses are increasingly touted as the solution to better sleep. But while marketing convinces us, many scientists remain skeptical. What do the studies really say and where is the balance between proven science and clever marketing?

What does science say?

Recently, a think tank of 250 experts, who have collectively published thousands of articles, concluded that blue light at night has a significant impact on our sleep. In fact, according to their findings, blue light disrupts our biological clock, suppresses melatonin production and increases the risks of obesity and diabetes. LED lights with a high factor of blue light are considered especially risky.

You can read the relevant article here. The article concludes that there is a strong scientific consensus on the importance of lighting impacting circadian rhythms and its impact on our health.

The recommendations include increasing exposure to bright light during the day and minimizing exposure to blue light at night to prevent disruption of circadian rhythms, which are associated with various health risks.

The article also suggests that “circadian lighting” should be widely used and that blue-rich LED lights should carry warnings of possible health risks when used during the night.

People diagnosed with DSWPD (Delayed Sleep-Wake Phase Disorder) have been found to have increased sensitivity to the phase-delaying effects of light compared to healthy control subjects. This increased sensitivity leads to a greater shift in circadian phase when exposed to light. This may contribute to the delayed circadian timing observed in DSWPD patients. Treatments for DSWPD should therefore consider limiting light exposure in the late evening hours to prevent relapse. You can read about that in this article.

Marketing and the claims

Meanwhile, you will find a very wide range of products on the market, such as blue-light-filtering glasses, which promise to solve many light-related sleep problems. Marketing campaigns use impressive percentages to emphasize the usefulness of these glasses.

However, some experts, such as the Dutch researcher Merijn van de Laar, argue that evidence for the effectiveness of these glasses on sleep quality and duration in clinical studies remains limited. This raises the question of whether these glasses actually contribute to a better night’s sleep or if we are dealing with a clever marketing trick.

What can we believe?

The reality often lies somewhere in the middle. However, current clinical tests do not yet demonstrate this. While the impact of light on our sleep is clear, the evidence that blue-light-filtering glasses significantly reduce this impact is not yet convincing enough.

It would be more realistic to inform consumers about the limited evidence and encourage them to take a holistic approach to better sleep, such as getting enough daylight, being wise about light in the evening, reducing screen exposure, and improving sleep hygiene.

Theory versus practice

It sounds logical that blocking blue light in the evening with filter glasses would help improve sleep, as the light signals to the brain that it is still daytime. Science also confirms that reducing bright blue light in the evening and using warmer light can be beneficial for the biological clock. While this is theoretically correct, practice reveals that blue-light-filtering glasses often do not have the expected effect on sleep duration and quality, according to Merijn van de Laar and others.

The problem lies partly in the gap between theory and practice. While it seems theoretically sensible, clinical research does not yet show a significant improvement when using these glasses. This may be due to the fact that other factors, such as the placebo effect, the amount of light you are exposed to during the day, and sensitivity to light in the evening, can influence the results. Therefore, it is recommended to absorb plenty of natural light during the day, limit the use of bright light in the evening, and switch to warmer light.

What does this mean for you?

For now, it is wise to be skeptical of claims made about blue-light-filtering glasses. Although it sounds logical, current research suggests that dimming lights and using warmer light is likely just as effective, if not more so. It is best to be aware of the difference between theoretical expectations and what has actually been proven in scientific studies.

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Can blue light glasses help you sleep – Conclusion:

Blue-light-filtering glasses can play a role in improving our sleep, but it is important to understand that the scientific support for their effectiveness is still developing. Not all glasses are the same, so inform yourself thoroughly. It is always wise not to blindly trust marketing claims and to consider a broader approach to tackling sleep-related problems.