Natural Light May Benefit Seniors' Biorhythms, Sleep and Health

Research exploring the interactions of light exposure, cataract development and older people's health shows that seniors may have both a higher need for natural light and a harder time getting it than do younger people. A part of the natural light spectrum, called blue light, is important for our ability to maintain healthy bodily rhythms. These are also called circadian rhythms or biorhythms.

When the lens in the eye ages, it gradually loses the ability to absorb blue light. When the brain receives less blue light, it produces less melatonin, a substance that regulates sleep-wake cycles. This increases the risk of insomnia and other sleep problems, which can be factors in serious conditions like depression and heart disease. Other studies have shown that when older people have their clouded lenses replaced in cataract surgery, their sleep, mood, and thinking processes improve as well as their eyesight.

Specific recommendations on how cataract surgery, exposure to natural light, and other methods could be used to support older peoples' health should be available soon from medical scientists.