Researchers are always coming up with fascinating new ways to study the connections between the body, the aging process and physical and emotional health. There are tons of studies that prove that there are many external factors that contribute to the risk of developing Alzheimer's disease, for instance. But one recent study has produced some intriguing insights linking your eyes to possible health and wellness woes.
Sunlight Impacts Your Mood - and Much More
You may be familiar with a condition called Seasonal Affective Disorder (SAD). This condition is best described as seasonal depression that almost always occurs during the winter months. This has been linked to the impacts natural sunlight has on the body and on your mood.
Who doesn't feel a sense of gratification or fulfillment when you take a moment, turn your face upward to the bright shining sun and just bask in the warm glow? Well, it turns out that aging eyes develop some problems that impact the amount of blue light that enters the eye. In turn, this disrupts your body's natural circadian rhythm and hormone levels -- which are linked to health and wellness.
Shift Workers at Higher Risk of Common Ailments and Health Conditions
Shift workers, who often have disruptions in circadian rhythm from staying awake to work at night and sleeping during the day. That means they're missing out on critical daylight hours to get the sunlight necessary to regulate the body's internal clock.
Studies show that the disruption in circadian rhythm leaves shift workers more susceptible to diseases and chronic conditions like insomnia, heart disease, and cancer. This leads researchers to question how other factors limiting light exposure impact circadian rhythms and health -- such as the eye itself.
The Aging Eye May Reduce Essential Light
The New York Times reports on research findings from Dr. Martin Mainster, a professor at the University of Kansas School of Medicine, and his wife, Dr. Patricia Turner, an opthamologist. As you age, the lenses of your eyes yellow over time and your pupils narrow, reducing the amount of light that enters.
This prevents ample light from reaching certain cells in your retinas, which are responsible for regulating your body's internal clock -- your circadian rhythm -- by controlling the secretion and suppression of two hormones:
- Melatonin, which promotes rest and repair, preparing your body for sleep.
- Cortisol, which helps regulate blood sugar, metabolism and other key bodily processes, promoting energy and alertness to tackle the day.
The aging eye starts to filter light sooner than you probably think. It's not a problem limited to the elderly; in fact, by age 45 the average adult is only getting about 50 percent of the light required to fully activate the photoreceptors in the retina, and thus the circadian system.
At age 55, the average person only gets about 37 percent of the necessary light, and by age 75, the average person gets only 17 percent of the light needed to fully stimulate the body's internal clock.
Older People Need More Light to Get the Same Benefits
Several studies ferment the relationship between light and melatonin suppression. One European study, for example, demonstrated that the same amount of light that suppressed melatonin in women in their 20s had no effect at all on women in their 50s. And that means that younger people will feel awake and energized with far less light than someone a few decades older. By controlling cortisol and melatonin, ample exposure to blue light leads to:
- Better memory retention
- Increased energy
- Feelings of wakefulness and alertness
- Improved mood
- Decreased sleepiness during the day
What It Means for Older Adults: Get More Sun!
The bottom line is that the older you get, the more sunlight (particularly blue light) you'll need to feel energized, alert, and content. Older adults have two disadvantages. One is that their aging eyes are filtering out more light due to the aging process.
The second is that older adults are more likely to spend more time indoors, which limits blue light exposure even further. Try to expose yourself to bright indoor lights, like fluorescent lighting, if you must be indoors during the day, and make an effort to get outdoors and soak up some natural sunlight.
Yes, extended exposure to UV rays is bad for your skin -- but great for your eyes and your body's internal clock. Make sure to protect your skin with sunscreen with an SPF of 15 or more.
Cataract Surgery Poses Another Challenge
Another problem faced by older adults who have had cataract surgery is that in about one-third of cataract surgeries, blue-blocking lenses are used as intraocular implants -- a practice established to reduce the risk of macular degeneration. This makes it even more difficult for those people to get ample blue light.
If your doctor recommends cataract surgery, discuss the risks and benefits of blue-blocking lenses with your surgeon. And if you've already had cataract surgery, that means you'll need to compensate with more exposure to blue light.
How does light impact your mood and energy levels? Do you suffer from the winter blues? What do you do to get more exposure to natural light during the dreary winter months? Tell us about it in the comments below.
Post by Angela Stringfellow