Can the iPhone's Night Shift mode be damaging to user health?

In January 2016, Apple introduced a new optional feature on iOS called Night Shift and received positive feedback from users. This is basically a feature that reduces the intensity of the blue light emitted from the screen of your iOS phone / tablet, thereby limiting negative effects to the eyes when you are forced to use the device in conditions. lack of light for a long time. After the success of Night Shift, many Android manufacturers have introduced similar features on their products.

However, a recent study by scientists from the University of Manchester (UK) has shown that features like Night Shift, in fact, can do more harm than bring. the real benefits.

The conclusion was based on the results of the study of mice with very simple logic: We are exposed to yellow light during the day (sunlight), this type of light closes. the dominant role during the time the sun is still present, overwhelming other types of light. When the sun goes down (sunset) the light tends to turn blue again. As a result, our bodies are more likely to be exposed to blue light during the evening and before bedtime.

Experimenting the effects of yellow and blue light on mice, the team found that at the same intensity, blue light had a weaker effect on the rat's circadian rhythm (less negative). This shows that we should have done the opposite of what Night Shift is applying.

'Using cooler, cooler light in the evening and warmer daylight during the day could have a more pronounced benefit,' said Dr Tim Brown, who led the research.

As such, the level and intensity of light are more of a concern than a color. Of course there are still slight differences between the effects of light on humans and mice, but a University of Manchester study raises the question: Is Night Shift and similar features really effective as advertised?

• Green light filtering applications must be available for your computer, phone