Natural light is the best light for your health and productivity at work but it is generally overlooked by employers.
A study conducted by the American Society of Interior Design discovered that 68 per cent of employees complain about the lighting quality in their offices.
The two most complained-about aspects of office lighting were either that the lighting was too dim, or too harsh. Both caused eye strain and headaches. Further, dim lighting caused drowsiness and lack of focus, while harsh lighting, such as florescent lighting triggered migraines and made it hard for the eye to focus.
The best alternative to harsh lighting and dim lighting systems is natural light itself. In a study conducted in Britain and published in ‘The Responsible Workplace’ it was shown that windows were the number one determinant of the occupants’ level of satisfaction with a building.
Natural lighting has been found to have positive effects on people’s mood, behaviour, hormonal balance and general wellbeing.
Natural lighting renovations have been shown to result in happier workers, less absenteeism, and fewer illnesses, and, because better lighting encourages satisfaction among workers, it also results in increased productivity. Energy cost savings and reduced contribution to greenhouse gas emissions are also benefits of natural lighting.
A study published in the scientific journal SLEEP Volume 36, compared the health of workers in windowless offices to those working in offices with windows allowing a flow of natural light.
Compared to the group with no windows, workers with windows in the workplace had 173 per cent more natural light exposure during the workday and slept an average of 47 minutes more per night, as well as sleeping more soundly and waking more refreshed. Workers with windows had more energy and vitality and undertook more activity during the day than their windowless counterparts, who showed more daytime dysfunction and tiredness.
The report said: “These results demonstrate a strong link between workplace daylight exposure and office workers’ sleep quality, activity patterns, and general quality of life.”
It suggested office workers increase their exposure to natural light through the day and that building design provide sufficient daylight exposure as it can improve workers’ physical and mental wellbeing.
The study said: “Exposure to natural daylight has profound effects on factors such as mood, cognition, sleep, health and behavioural measures.
The study reported on research by the Interdepartmental Neuroscience program at Northwestern University in Chicago, which also clearly showed detrimental health effects on workers who worked in windowless offices.
Compared to workers in offices without windows, those with windows in the workplace received 173 percent more white light exposure during work hours and slept an average of 46 minutes more per night. Workers without windows reported lower scores than their counterparts on quality of life measures related to physical problems and vitality. They also had poorer outcomes in measures of overall sleep quality, sleep efficiency, sleep disturbances and daytime dysfunction.
"The extent to which daylight exposure impacts office workers is remarkable," said study co-author Ivy Cheung, a Neuroscience doctoral candidate at Northwestern University.
Light is the main cue influencing circadian rhythms. Exposure to natural light turns the genes that control an organism’s internal clocks "on" and "off." Circadian rhythms dictate: sleep-wake cycles, hormone release, body temperature and other important bodily functions.
Disruptions of circadian rhythms such as experienced by workers who lack exposure to natural light is directly linked to sleep disorders. Abnormal circadian rhythms have also been associated with obesity, diabetes, depression, bipolar disorder and seasonal affective disorder (SAD).
The study concluded that sleep disorders caused by lack of exposure to natural light had reached epidemic proportions.
Ivy Cheung and her colleagues at Northwestern conclude, “the architectural design of office environments should take into consideration how natural daylight exposure may contribute to employee wellness.”
If you are currently working in a windowless environment—or suffer from seasonal affective disorder (SAD) in the wintertime—you can greatly impact the SCN and your circadian rhythms by using a light box that mimics outdoor light. For more details on what to consider when choosing a light box, you can check out this link from the Mayo Clinic.
Understanding a light box
A light therapy box mimics outdoor light. Researchers believe this type of light causes a chemical change in the brain that lifts your mood and eases other symptoms of SAD.
Generally, the light box should:
- Provide an exposure to 10,000 lux of light
- Emit as little UV light as possible
Typical recommendations include using the light box:
- Within the first hour of waking up in the morning
- For about 20 to 30 minutes
- At a distance of about 16 to 24 inches (41 to 61 centimetres) from the face
- With eyes open, but not looking directly at the light
Light boxes are designed to be safe and effective, but they aren't approved or regulated by the Food and Drug Administration (FDA) for SAD treatment, so it's important to understand your options.
You can buy a light box without a prescription. Your doctor may recommend a specific light box, but most health insurance plans do not cover the cost.
What to consider
Here are some questions to think about when buying a light box for seasonal affective disorder:
- Is it made specifically to treat SAD? If not, it may not help your depression. Some light therapy lamps are designed for skin disorders — not for SAD. Lamps used for skin disorders primarily emit ultraviolet (UV) light and could damage your eyes if used incorrectly. Light boxes used to treat SAD should filter out most or all UV light.
- How bright is it? Light boxes produce different intensities of light. Brighter boxes will require less time to use each day, compared with dimmer boxes, to achieve the same effect. Typically the recommended intensity of light is 10,000 lux.
- How much UV light does it release? Light boxes for SAD should be designed to filter out most or all UV light. Contact the manufacturer for safety information if you have questions.
- Can it cause eye damage? Some light boxes include features designed to protect the eyes. Make sure the light box filters out most or all UV light to avoid damaging your eyes. Ask your eye doctor for advice on choosing a light box if you have eye problems such as glaucoma, cataracts or eye damage from diabetes.
- Is it the style you need? Light boxes come in different shapes and sizes, with varied features. Some look like upright lamps, while others are small and rectangular. The effectiveness of a light box depends on daily use, so buy one that's convenient for you.
- Can you put it in the right location? Think about where you'll want to place your light box and what you might do during its use, such as reading. Check the manufacturer's instructions, so you receive the right amount of light at the proper distance.
Talk to your health care professional about light box options and recommendations, so you get one that's best suited to your needs.