Today, May 16th, is the @internationaldayoflight Light! 💡
Light should be a public health priority, but it’s not. We have public health guidance warning about UV light, and advice on vitamin D. But there are no public health messages on how light affects the biological clock and circadian system, despite four decades of research.
Light is a powerful signal that influences key aspects of our health. It;s one of the strongest signals reaching your body. And data from over 88,000 individuals indicate that it can affect mood, mental health, sleep, alertness and possibly influence diseases like depression and type 2 diabetes.
This information has been missing from the public conversation. We want to urge health organisations and health professionals to share this message with the public.
⏰ For every individual, simple behavioural changes can already help get a healthy light exposure pattern, without the need for special lamps or devices.
☀️ Get outside in the morning. Outdoor light, even on a cloudy day, is far brighter than any indoor source.
🪟 Sit near a window when you are indoors. Natural light through glass is still more effective than most artificial lighting.
🌙 Dim your lights two to three hours before bed. Evening light delays the body clock and suppresses melatonin.
📱 Keep screens dim in the evening. Reducing screen brightness matters more than switching colour temperature.
🛏️ Sleep in darkness. Even low light levels during sleep can affect sleep quality and circadian timing.
Twenty-one scientists distilled four decades of research into 26 consensus statements on light and human health. The statements reflect the current state of knowledge across photobiology, circadian physiology, and sleep medicine.
#lightforpublichealth #publichealth #circadianhealth #sleep #light
New “chrono-schedule” helps nurses recover faster after night shifts
Jeroen Bosch Hospital (JBZ) in Den Bosch, the Netherlands, has reported encouraging early results from a new night-shift system called a “chrono-schedule”. In a pilot study, nurses working under the new system said they felt less exhausted after night shifts, had less difficulty staying awake, and recovered more quickly afterwards.
Read our article and learn more, link in bio
#goodlight #qualityoflife #health #lighting #circadianrhythm
Step 4 how to manage light in the evening
Sleep doesn’t start when your head hits the pillow, it begins hours earlier with the signals you send your brain. One of the most important signals is light. To support deep, restful sleep, it’s recommended to keep light levels below 10 lux starting three hours before bedtime.
How to keep your light below 10 lux:
• Dim the Lights
• Close the Curtains
• Avoid Bright Screens
• Create a gentle transition to sleep
#goodlight #qualityoflife #health #lighting #circadianrhythm
Can’t sit near a window?
Step 3: Use high-quality electric lighting during the day
When natural daylight isn’t enough, especially in windowless rooms or when your desk is more than a meter away from a window, high-quality electric lighting is essential. Poor or insufficient lighting can leave your body in a “low-energy” state, even if you feel mentally busy.
• Ensure your eyes receive at least 500 lux during the daytime
• Use bright, evenly distributed lighting rather than a single dim lamp
• Choose lighting designed for daytime use that compensates for the lack of daylight
• Reaching 500 lux at eye level helps signal to your brain that it’s daytime, supporting focus, productivity, and mood. This is especially important if you work indoors for long hours.
#goodlight #qualityoflife #health #lighting #circadianrhythm
Spending time outdoors is ideal, but many of us still spend large portions of the day inside. When natural daylight is limited, optimizing your indoor light environment becomes essential for maintaining energy, focus, and a healthy daily rhythm. This simple step can make a big difference.
Step 2: Stay within one meter of a window
Working, reading, or relaxing near a window helps:
• Support your circadian rhythm
• Improve alertness and concentration
• Reduce eye strain compared to dim indoor spaces
#goodlight #qualityoflife #health #lighting #circadianrhythm
Step 1 of the four steps to live a healthier live in good light
Spend at least 2 hours outside during the day
In our busy, screen-filled lives, it’s easy to spend most of the day indoors. But making time to step outside, particularly in the morning, can have a huge impact on your overall health and well-being. In fact, scientists recommend spending at least 2 hours outside during the day, with a good portion of that time in the morning if possible.
#goodlight #qualityoflife #health #lighting #circadianrhythm
Does daylight at the office improve metabolic health?
Read now! A new blog post by Ivo Habets
The circadian timing system regulates many processes in the human body. While it is best known for controlling our sleep–wake cycle, metabolism also follows a strong daily rhythm. Glucose regulation, insulin sensitivity, and substrate use all fluctuate throughout the day in a coordinated way.
And the key driver of this rhythm?
Natural daylight.
But what happens when most of our day is spent indoors under artificial lighting?
Explore new research showing that natural daylight exposure during office hours can improve glucose control and influence whole-body substrate metabolism in people with type 2 diabetes.
A small environmental change, with potentially meaningful metabolic impact.
Read the full article on our website, link in bio
#circadianrhythm #daylight #workplacewellbeing #goodlight #qualityoflife
A blog by Aida Farshadi, PhD
For millions of years, humans lived under the full spectrum of sunlight. Our physiology evolved not just with visible light, but also with near-infrared light (NIR), an invisible wavelength that makes up nearly half of the sun's energy reaching Earth.
A lack of NIR may contribute to common complaints of modern indoor life: fatigue, poor sleep, reduced alertness, and slower recovery. While definitive causal links are still under investigation, the emerging picture suggests that NIR is not a luxury; it's closer to an environmental nutrient we've unknowingly removed from our daily lives.
Read the blog of Dr. Aida Farshadi on our website and learn what near-infrared light is, why we're missing it and what we can do.
/post/the-hidden-part-of-sunlight-why-near-infrared-light-matters
#goodlight #qualityoflife #health #lighting #circadianrhythm
It’s Blue Monday, often described as the “most depressing day of the year”. Three weeks in the new year, mostly in cloudy, rainy of snowy weather has brought the mood down of many.
Here are some tips and tricks to help you get through this day:
Get a lot of daylight: We recommend spending up to two hours outside, especially in the morning. But every short walk outside does already help.
Move your body: If you’re going to work out, try to do it near a window so you can get some daylight and enjoy a double boost.
Eat well: Choose healthy foods and walk to the shops to buy your groceries instead of taking the car. This way, you’ll get some exercise, fresh air and daylight at the same time.
What if you have to work all day and don’t have time for this?
Check our website to learn more! Link in bio.
#goodlight #qualityoflife #health #bluemonday #circadianrhythm
Ook in 2026 helpt een goed lichtdieet met beter slapen, energie en een vrolijkere stemming
#christmas #santa #carpelucem #lichtdieet #2026 @goodlightgroup
This 1 thing could save your mood this winter, and almost everyone ignores it.
Did you know? Getting 1 hour or more of daylight every day from November to January might mean NO depressive symptoms this season!
Even more striking: when daylight exposure drops below 1 hour a day, the likelihood of struggling increases dramatically. With enough daylight, the odds fall significantly.
Winter darkness isn’t the problem…
your daylight exposure is.
Want the science behind it? Read the blog by Research Professor Timo Partonen and learn more.
🔗 Link in bio
#goodlight #qualityoflife #health #lighting #circadianrhythm
Every living organism on earth follows internal 24-hour cycles known as circadian rhythms. From a flower opening at dawn to a surge of human alertness in the mid-morning, these rhythms are deeply embedded in our biology. They regulate countless processes, from gene expression and metabolism to behaviour and sleep.
In mammals, the central pacemaker of this system is located in the suprachiasmatic nucleus (SCN) of the hypothalamus. The SCN synchronises peripheral clocks that exist in nearly all tissues through neural, hormonal and behavioural signals. Light, especially short-wavelength, blue-white light detected by specialised retinal cells in the eye, serves as the primary environmental cue that entrains the SCN with the Earth’s natural day-night cycle.
Learn more, link in bio
This short blog is inspired by the book On the Essential Principles and Practice of Circadian Biology: A Road Map by Roelof A. Hut and William J. Schwartz.
#goodlight #qualityoflife #health #lighting #circadianrhythm
