A review on effect of Blue-Light exposure before sleep on melatonin levels

Sarah Arissa Binti Dzulbahri; Nur Ainul Safiya Binti Muhamad Fazil Sakirin; Damia Alya Binti Noor Hadi

Authors

Sarah Arissa Binti Dzulbahri Faculty of Pharmacy, University Sultan Zainal Abidin, Terengganu, Malaysia
Nur Ainul Safiya Binti Muhamad Fazil Sakirin Faculty of Pharmacy, University Sultan Zainal Abidin, Terengganu, Malaysia
Damia Alya Binti Noor Hadi Faculty of Pharmacy, University Sultan Zainal Abidin, Terengganu, Malaysia

Keywords:

Light-Emitting Diodes; Melatonin; Mobile Devices; Screen Time; Sleep Hygiene.

Abstract

Melatonin is a vital hormone for maintaining the body’s sleep state. Melatonin supplements can be taken by individuals who have difficulty maintaining a consistent sleep schedule. From the National Institute of Health, a 2017-2018 survey was conducted and found that 2.1% of adults take melatonin to help them. Good sleep practices must be committed before taking melatonin supplements, since supplements can be the last resort. One of the most important sleep practices is to limit screen time two hours before bedtime. The light from the phone screen is a technology called light-emitting diode (LED) that contains blue light. Excess exposure to blue light is very concerning for our eye health, such as eyestrain, and affects the sleep-wake cycle. This study reviews 35 articles about the effect of blue light from any sources, mainly mobile devices, on our melatonin secretion. It also tackles the hazardous factors of blue light and which type of people will be affected thoroughly by this problem. A wide variety of search engines and databases, such as PubMed and Google Scholar, were used to find certain articles that related to this study’s aim.

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