Growing researches have indicated that light can impact human health in numerous ways, including susceptibility to Alzheimer’s disease. The question is: What exactly can ageing people do to help their eyes and health?
According to researchers, the combination of damaged nerve pathways caused by Alzheimer’s disease and normal deterioration of the eyes due to ageing means that levels of light (especially indoors) are not usually sufficient to signal that it is daytime. If the internal body clock is not tuned in to the usual daily pattern, this affects not only the wake-up process but also the activity and sleep cycles that come into force in the evening.
A growing number of studies show that better and brighter lighting can help improve sundowning, one of the symptoms more common in advanced cases of Alzheimer’s, and reduce sleep/wake disturbances, particularly in the most severe cases.
Lighting becomes more important as people age. According to the American Lighting Association (ALA), with each passing year, everyone requires more light to see properly. Terry McGowan, director of engineering for the ALA, says, “Older eyes experience two important changes.”
First, the amount of light required to sustain visual performance increases with age. Research shows that a 60-year-old needs twice as much light as a 30-year-old.
Second, with time, human eyes become more sensitive to glare. This can seem like a bit of a Catch-22, as more light can often result in increased glare. That’s what makes the quality of light more important as you grow older.
With people reaching their mid-60s, homeowners should consider user age as a factor in their home-lighting design. It is easy to enhance the visual performance and enjoyment for older folks with a few simple lighting adjustments.
Turning on one or two table lamps while watching television to reduce the contrast between the bright screen and the surrounding darkness is a good way to do it.
One can use a torchiere for uplighting as well as downward illumination for versatility. Look for a fixture with a separate task light attached or one with a glass bowl at the top to shine some light downward. It is also a good idea to have a task light that can be directed or pivoted. In addition to providing sufficient light, proper lighting design is essential to human health.
“As people get older, it isn’t just the amount of light, it is also the colour of the light and when it is applied, that is key to regulating things such as circadian rhythm and REM sleep cycles,” says McGowan.
The answer, according to McGowan, is to enjoy bright days and dark nights. “If you’re older and don’t sleep very well, expose yourself to bright light, such as daylight, early in the morning. A walk outside will do it and sleep in a dark room at night. That will do everything required to regulate your circadian rhythm,” says McGowan.