Blue light is part of the visible light spectrum and comprises of electromagnetic radiation with wavelengths ranging from 420 - 490 nm. Although the range up to 420 nm would be considered violet, the entire range from 400 to 490 nm is often referred to as blue light. Therefore, it is right at the border of the UV range which is invisible to the human eye. Blue light has among the visible radiation the shortest wavelengths and therefore has particularly high energy. It is also known as HEV light, which is the abbreviation for "High Energy Visible". 

Natural blue light generated by the sun has a significant influence on our life. It acts as our inner clock. When we absorb the sun’s blue light during the day, there are certain processes and hormones set in motion in the body that help us get through the day feeling energized, alert and healthy. When the sun is bright, our body accumulates serotonin and cortisol which prevents the production and release of our sleep hormone melatonin. As the amount of blue light decreases in the afternoon towards evening, the body's own process is reversed making us tired. This allows sleep to take over making sure we relax and get our rest. Since the dawn of time, our rhythm of life, our activities and our well-being have been determined by the sun.

But today looks somewhat different. With increasing artificial light sources, our day-night rhythm is being influenced leading to inner restlessness and even sleep disorders for many people. Especially in large cities you often hear talk about "light pollution". Artificially generated light resets the inner clock and turns it upside down. For example, when a night is "bright", much less melatonin can be released, making it harder for the body to go to sleep.

There are enough findings and evidence in relation to the impact of UV radiation. We know about both positive and negative effects, also on people. Here again, the following applies: The quantity makes the poison. Sun protection product development and the improved quality of UV filters started many years ago based on these findings. However, researching the field of blue light is relatively new in this area. Good sun protection clearly indicates on their label that they protect against UVA AND UVB. But have you seen products saying they protect the skin from blue light? These products exist. They can be realized using for example BASF's UV filters Tinosorb^® A2B and Tinosorb^® M, which can reduce the exposure to blue light. In another upcoming article, along with our experts from Grenzach, we will look closer at exactly how they work and their advantages for customers.