Your browser is no longer supported

For the best possible experience using our website we recommend you upgrade to a newer version or another browser.

Your browser appears to have cookies disabled. For the best experience of this website, please enable cookies in your browser

We'll assume we have your consent to use cookies, for example so you won't need to log in each time you visit our site.
Learn more

Colour of work lighting affects mood of night shift staff


Night-shift nursing staff would be happier working under red lights, rather than white or blue, new research suggests.

US scientists found that exposure to blue light at night can depress night-shift workers, white lowers moods less, while red is the least disturbing colour, according to US scientists.

Researchers, who say their findings gained from tests on hamsters would also be applicable to humans, suggest the results have vital implications for nurses and other night-shift staff.

They claim that round-the-clock workplaces should ideally be red lit at night.

Head researcher Professor Randy Nelson, from Ohio State University, said: “Our findings suggest that if we could use red light when appropriate for night-shift workers, it may not have some of the negative effects on their health that white light does.”

Scientists subjected hamsters to nights with no light, or lit by low-level red, white or blue light.

The rodents were then tested for depressive symptoms.

One sign that hamsters are unhappy is that they lose interest in sugar water, which they usually enjoy.

The findings revealed that hamsters left in the dark at night for a month consumed the most sugar water, followed by those exposed to red light.

White light seemed to drop the animals’ mood, and blue light depressed them even more.

Rodents that spent nights in blue or white light had substantially fewer dendritic spines than those exposed to complete darkness or red light.

Dendritic spines are hair-type growths on brain cells that are used to transfer chemical signals.

Reduced dendritic spine density has previously been associated with depression.

Co-author Dr Tracy Bedrosian, also from Ohio State, said light at night may have unwanted effects on mood-regulating brain regions.

People could benefit from avoiding the blue and white glow of computers, televisions and other electronic devices at night, said the researchers.

The results are published in The Journal of Neuroscience.


Are you able to Speak out Safely?

Sign our petition to put pressure on your trust to support an open and transparent NHS


Readers' comments (2)

  • Complete and utter bo!!ocks, quite frankly. Having adequate staff affects staff mood!

    Unsuitable or offensive? Report this comment

  • it is keeping awake at night that is the issue more than depression regardless of dendritic spines and hair growth on the brain! what sort of light is needed to keep nurses awake.

    I am not a hamster or a nocturnal creature. Their habits are totally different from mine. I should know as I had two hamsters when I was little and they seemed very happy little creatures. one was so happy it escaped from its cage in a pet shop who were supposed to be looking after him when we were on holiday. it found its way into a sack of grain where it gorged itself to death. I was devastated. it was cream, very pretty and called Reekie (the old name for Edingburgh). It was well looked after and had a shorter and happy little life (or at least as happy as one can be living in a cage) in daylight when it slept, and in the evenings when it was very active and came out to play.

    The other lived much longer than average and was also very happy. it one day squeezed through the bars in its cage and after much searching we found it happily curled up sleeping in the carpet sweeper where it had made a cosy nest out of the fluff and had a good store of food it had taken with it!

    we need to do further experimentation with light to see which is the most effective for night nurses and their dendritic spines and not hamsters and at the same time ensure appropriate and adequate staffing levels.

    Unsuitable or offensive? Report this comment

Have your say

You must sign in to make a comment

Please remember that the submission of any material is governed by our Terms and Conditions and by submitting material you confirm your agreement to these Terms and Conditions. Links may be included in your comments but HTML is not permitted.