Blue light is emitted by mobile phones, computers, e-readers, televisions and even the streetlights of many cities. For this reason, the vast majority of people are exposed to it on a daily basis.
Too much of this artificial light could have detrimental side effects on many aspects of human health, especially at night. So much that some experts do not hesitate to point out it as a growing public health problem.
Light is the most important synchronizer of human circadian rhythms. Cells in the retina respond to short-wavelength light, which comes from a cloudless blue sky, but also from blue light. As light rays hit these cells, the brain stops producing melatonin to focus on hormones like cortisol and ghrelin, that wake us up and make us hungry.
There is evidence to suggest that exposure to blue light would not only cause sleep problems, but also weight gain, depression, heart disease, and cancer. So far the cause and effect relationship has not been confirmed, but for many experts, there is data alarming enough to warrant immediate action.
If you want to prevent damage attributed to blue light, do as on the International Space Station, where they darken and shift the light to a longer wavelength as night falls. Consider dimming the lights and stepping away from bright blue screens at night. Use blue light filters on your glasses or install them directly on electronic devices such as phones and tablets. You can also change the display settings to warmer tones. Replacing bedroom lights with longer wavelength lights, and investing in a sleep mask if streetlights shine on your window are also among the most widely used strategies.