Blue light is visible light with the shortest wavelength but has the highest energy. This type of light is both useful and harmful to human health. The natural source of blue light is mainly sunlight, which is beneficial to boost concentration and alertness. Also balancing the body's circadian rhythm - the natural wake and sleep cycle. Meanwhile, artificial sources of blue light come from bulbs or digital screens. 

In fact, blue light exposure from man-made sources is negligible compared to that from natural sources. Still, blue light from artificial sources causes long-term effects on human health due to the time and distance of direct exposure. Nowadays, electronic devices are on the rise and becoming more popular, increasing the amount of blue light exposure.

Long-term exposure to blue light might cause to many health problems (Source: LMC)

Besides the obvious effects of blue light on eyes due to direct exposure. Excessive screen time leaves negative effects on mental health and well-being, including sleep and mood. Exposure to blue light before bedtime can cause sleep disorders as it reduces melatonin production - a hormone that regulates the sleep cycle. Melatonin suppression during nighttime reduces sleep hours and sleep quality. Whilst, sleep is a determinant factor for good health. Insufficient sleep is the main cause of a tired body, lack of energy for the next day, and increases the risk for long-term health concerns. A paper by Harvard Health Publishing researched that blue light has the potential to cause cancer, heart disease, diabetes, and obesity. 

Continuous exposure to blue light disrupts the circadian rhythm, which is also closely linked to our feelings and emotions. This disruption might lead to anxiety, depression, and fatigue. 

Blue light has significant impacts on mental health

Limiting blue light exposure to the minimum potentially contributes to a healthy life. Some solutions are suggested to ease the blue light’s effects on mental health:
- Avoid using electronic devices 2-3 hours before bed
- Reduce the screen brightness and use night shift mode
- Use blue-light filter techniques for digital devices
- Use more yellow-toned bulbs at home and in the working area instead of white-toned ones. The warm lighting might decrease the amount of blue light exposure at night. 


Mia Dinh