A Window To Our Wellbeing

Posted on 21 JAN

How natural light keeps us happy, healthy and productive

Light is one of the most underutilised, free health commodities that is critical to a multitude of processes in the human body. It controls our circadian system, can improve immune function and reduce depression, fatigue and pain.


Light has been shown to decrease agitation amongst dementia patients and decrease the length of patients’ stays in hospitals. The presence of windows in the workplace has been linked with increased satisfaction with the work environment. There are a number of critical hormones and chemical reactions within the body that are affected by light. Exposure to light is critical for vitamin D metabolism in the body, which plays an important role in the immune system and respiratory health in particular. With respiratory viruses like COVID-19 having such an impact on society today, the health of the population is more important than ever.


The clearest effect of light on humans is in the performance of visual tasks. Not only is the amount of light available to the subject important, but the spectrum and distribution of the light is also key to determining the levels of performance of visual tasks (1). Boyce and his colleagues found that natural lighting from the sun was superior to artificial light when it came to performing tasks involving fine colour discrimination. Another study found that pharmacists’ error rate, when dispensing prescriptions, was lower with higher light levels (2).

Circadian system

The production and suppression of melatonin at the correct times is key to feeling energised during wakeful hours and to high quality sleep at night. Light exposure supresses melatonin (3) and leads to a state of alertness (4)(3). Inadequate light exposure, and therefore high melatonin levels during wakeful hours, leads to feelings of sleepiness and depression (5). It has been found that outdoor daylight is more effective at controlling circadian rhythms than most artificial light sources (1). We can see that by having more access to daylight, whether that be from skylights and windows or open air, people will feel more energised throughout the day and sleep better at night.

Health and Immune System

The metabolism of Vitamin D is one of the best-known beneficial effects of sunlight exposure. Vitamin D is unique because it can be made in the skin from exposure to the sun. It is estimated that 1 billion people worldwide have a vitamin D deficiency (6). In the Journal of pharmacology & pharmacotherapeutics, Nair and Maseeh cite that “Emerging research supports the possible role of vitamin D against cancer, heart disease, fractures and falls, autoimmune diseases, influenza, type-2 diabetes, and depression”. This shows the wide-ranging effects that inadequate sunlight exposure can have on the health of humans. An article by Weir and Colleagues even suggests potential mechanisms linking COVID-19 severity and Vitamin D deficiency (7). Low Vitamin D levels have also been associated with a significantly increased risk of pneumonia and viral upper respiratory tract infections (7). With so many different health outcomes being linked with a deficiency of sunlight, it only makes sense that our buildings should be designed to ensure adequate amounts of natural light reach occupants. Having access to daylight can reduce stress and increase work satisfaction


"Having access to daylight can reduce stress and increase work satisfaction"


Light in the Workplace

Different lighting conditions have been shown to affect the moods of people (1). Having better lighting conditions can therefore lead to a happier workplace. A study found that people prefer daylight to artificial sources of light and prefer to be closer to windows at work. It seems natural that humans would prefer to be close to the daylight and views that windows provide, considering our evolutionary history and the calming effect that nature has on us.

Having access to daylight can reduce stress and increase work satisfaction (8). The study found that nurses exposed to daylight for 3 hours a day were less stressed and had greater job satisfaction.

The effectiveness of clever fenestration design was shown when a new medical facility that incorporated atriums and increased access to windows was built. The company found that 70 percent of its staff reported a positive impact due to the increased natural light on their work life (9).


There is an excess of fascinating research, some over 20 years old, showing just how important it is for the health of our employees to have adequate access to natural lighting. Since many workers spend close to 8 hours a day sitting at their desk, what better way to improve their health, wellbeing and productivity than by providing high quality glazing solutions. Wherever possible, natural lighting should be incorporated into a buildings design because it is not only highly beneficial to people’s wellbeing, but because natural light is cost-free. It is important to take the glare and heat caused by natural light into account by using solar shading and specific design glass. In order to achieve this, windows must be designed with solar and thermal performance in mind.

Woods Glass offers Products like Infinit E (low emissivity glass) and ThermalPlus (insulating glass units) to reduce the amount of heat transfer through glass, making the inner space more comfortable. These can be combined with Woods Glass’ Keramo (ceramic fritted glass) for a combination of glare and solar control, as well as providing privacy and aesthetic designs.

With all the health and wellbeing benefits that natural light provides – perhaps high-quality glazing on all buildings should be a leading public health initiative implemented by countries worldwide.




1. Daylight exposure and the other predictors of burnout among nurses in a University Hospital. Alimoglu, Mustafa Kemal and Donmez , Levent. 2005, International Journal of Nursing Studies, pp. 42(5), 549-555.

2. Boyce, Peter, Hunter, Claudia and Howlett, Owen. The Benefits of Daylight through Windows. Troy, NY : Rensselaer Polytechnic Institute., 2003.

3. Illumination and errors in dispensing. Buchanan, T L, et al. s.l. : American journal of hospital pharmacy, 1991.

4. Edwards, L and Torcellini, P. Literature Review of the Effects of Natural Light on Building Occupants. United States : National Renewable Energy Lab, 2002.

5. Supersensitivity to light: possible trait marker for manic-depressive illness. Lewy, AJ, et al. s.l. : Am J Psychiatry, 1985.

6. Full-spectrum fluorescent lighting: a review of its effects on physiology and health . McColl, S L and Veitch, J A. s.l. : Psychol Med, 2001, Vol. 31(6).

7. Hospital design and staff perceptions: an exploratory analysis . Mroczek, Jana, et al. s.l. : The health care manager.

8. Vitamin D: The “sunshine” vitamin. Nair, Rathish and Maseeh, Arun. s.l. : Journal of pharmacology & pharmacotherapeutics, 2012, Vol. 3(2).

9. Does vitamin D deficiency increase the severity of COVID-19. Weir, E Kenneth, et al. London : Clinical Medicine (London, England), 2020, Vol. 20(4).