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Commentary | HCL | Health + Wellbeing | Jan 13, 2021

Good Light Helps Prevent Winter Dip

The holidays are over, it's cold and dark, we prefer to sit inside. Nevertheless, you need a daily portion of good light: it makes you more energetic, happier, and healthier. Make sure that you go outside for a good time every day and that you also have enough good light indoors during the day. Daylight is best, but there are also good alternatives with LED lighting and light therapy lamps.

Especially at this time of year, this can help prevent the so-called winter dip. A quarter of people in the northern hemisphere suffer from winter malaise. A winter dip has specific symptoms such as being unenergetic, not enjoying regular activities, and sleeping longer. Fortunately, the winter dip only leads to winter depression in four percent of people at which point medical attention is needed.

By the time the new year rolls around, everyone has already had a long period of very short days and new year's resolutions are proving to be a lot more difficult to achieve in practice. The endless lockdown due to COVID 19 doesn't help improve our moods either. The sun shows very little, it is cold and gloomy. The mood of many people falls to a low point. We are in the most depressing period of the year and the third Monday of the year is a symbol of this and aptly named “Blue Monday”.

What can you do about this?
In the first period of the year, people really fall short of daylight. If you don't get enough daylight for a day, your biological clock will be about 10 to 15 minutes behind on average. Eight o'clock in the evening feels like quarter to eight. It works cumulatively: those who stay indoors for a week and don't see daylight are an hour and a half behind. You get a feeling similar to jet lag. You're tired, less alert, and your mood is down. In short, light is needed to keep the biological clock in line. In the eye, on the retina are receptors: rods, cones and spheres. Those spheres are important for correcting your biological clock. The spheres are sensitive to the cyan blue part of the light spectrum and pass the information on to your biological clock in your brain.

A large part of the world's population lives and works in biological darkness. For the record: normal electric light in your home and also the lighting in companies and offices equates to biological darkness. The light  enables visual tasks, but is too weak to positively influence the biological clock. Fortunately, nowadays there are lamps and luminaires that imitate daylight as effectively as possible. They can't fully mimic daylight, but being exposed to enough intense light in the house can help protect you from experiencing the winter dip.

Author: Jan Denneman
Chairman and founder of the Good Light Group, non-profit organization promoting the use of good light for health and wellbeing.


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