Such concerns are not new -- Thomas Edison may have created these problems when he invented the light bulb. But the problem has grown worse thanks to the popularity of Apple's new slate computer, the iPad.
Many consumers use an iPad to read at night, and unlike paper books or e-book readers like the Amazon Kindle, which does not emit its own light, the iPad's screen shines light directly into your eyes from a relatively close distance.
According to CNN:
"That makes the iPad and laptops more likely to disrupt sleep patterns than, say, a television sitting across the bedroom or a lamp that illuminates a paper book, both of which shoot far less light straight into the eye, researchers said."
Everything in nature has a rhythm, and that includes your body. The ebb and flow of the ocean's tide, the rising and setting of the sun, and the transition from one season to another all happen with comforting regularity. Your body, too, strives to keep its 24-hour cycle, or circadian rhythm, steady and even.
This is why most of us naturally feel like waking when the sun comes up, and sleeping when it's dark.
Researchers have also shown how your circadian rhythm is involved in everything from sleep, to weight gain, mood disorders, and a variety of diseases.
Unfortunately, modern life throws multiple wrenches into the works, as it were, mainly by artificially extending 'daytime.'
Glowing Gadgets Fool Your Brain and Disrupts Your Circadian Rhythm
The advent of the light bulb may have been bad enough, but today there are any number of glowing gadgets tricking your brain into thinking it's still day time, well past sundown.
This extended exposure to artificial light can disrupt your sleep cycle and make minor insomnia worse.
Why is that so?
Because when light receptors in your eyes are triggered, they signal your brain to 'stay awake.' To do that, your brain stops secreting melatonin, which is both a hormone and a potent antioxidant against cancer.
Normally, your brain starts secreting melatonin around 9 or 10 pm, which makes you sleepy. These regularly occurring secretions thus help regulate your sleep cycle. However, if you regularly trick your brain into altering this cycle, sleep disturbances are not far behind. It can even create a state of permanent "jet lag."
The trouble with many of the electronic gadgets available today is the type of light they emit.
Computer screens and most light bulbs emit blue light, to which your eyes are particularly sensitive simply because it's the type of light most common outdoors during daytime hours. As a result, they can disrupt your melatonin production.
The CNN article above details one man's personal experiment to test the veracity of the claim that night time light exposure will disrupt your sleep.
"J.D. Moyer decided recently to conduct a little experiment with artificial light and his sleep cycle. The sleep-deprived Oakland, California, resident had read that strong light -- whether it's beaming down from the sun or up from the screens of personal electronics -- can reset a person's internal sleep clock.
So, for one month, whenever the sun set, he turned off all the gadgets and lights in his house -- from the bulb hidden in his refrigerator to his laptop computer.
Instead of falling asleep at midnight, Moyer's head was hitting the pillow as early as 9 p.m. He felt so well-rested during the test, he said, that friends remarked on his unexpected morning perkiness.
"I had the experience, a number of times, just feeling kind of unreasonably happy for no reason. And it was the sleep," he said. "Sure, you can get by with six or seven hours, but sleeping eight or nine hours -- it's a different state of mind."
Daytime Light Exposure Matters as Well
Yes, the quality of the light you're exposed to during the day also matters when it comes to maintaining a healthy rhythm. While most of us are over-exposed to light in the evenings, most of us are also under-exposed to light during the day!
Most incandescent- and fluorescent lights emit very poor quality light. What your body needs for optimal functioning is the full-spectrum light you get outdoors.
Using full spectrum light bulbs in your home and office can help ameliorate this lack of high quality sunlight during the day.
For use in the evening, you can now purchase "low blue lights." These light bulbs emit an amber light opposed to the blue that suppresses melatonin production. Therefore, these bulbs are ideal for areas such as your bedroom and bathroom, for example. You could also use them in your living room.
As mentioned earlier, TVs and computers also emit a lot of blue light, which will zap your melatonin if you work past dark, so ideally, you'd want to turn these items off once the sun goes down.
Keep in mind that even a small amount of light, like keeping a night light on, or turning on the bathroom light to go to the restroom, can be enough to suppress the melatonin production for that night. So, if you have to get up, try to resist the temptation to turn on the light.
This is also why I strongly recommend installing blackout shades to ensure complete and total darkness in your bedroom.
Your Circadian Rhythm is Closely Tied to Your Overall Health
Your circadian rhythm has evolved over many centuries to align your physiology with your environment. However, it is operating under the assumption that you're still behaving as your ancestors have for generations: sleeping at night and being awake during the day.
If you push these limits by staying up late at night, depriving yourself of sleep, or even eating at strange hours (such as at 2 a.m.), you are sending conflicting signals to your body. As a result, you body doesn't know whether it should be producing chemicals to tell you to go to sleep, or gear up for the beginning of your day.
But maintaining this natural circadian rhythm affects far more than just your sleep pattern. Your body actually has many internal clocks -- in your brain, lungs, liver, heart and even your skeletal muscles -- and they all work to keep your body running smoothly by controlling temperature and the release of hormones.
Your body temperature and hormone production also vary with your personal internal clock. This, in turn, influences such things as:
- The easiest time to detect disease in your body
- The times when you'll be less sensitive to pain
- The times when you'll be more productive at work
Disrupting your natural rhythm can also make you more vulnerable to disease. For example, reduced melatonin levels, due to prolonged exposure to light, is known to increase your risk of cancer.
It also activates your stress response and weakens your immune system, which is why irregular sleep cycles can lead to stress, constipation, stomach ulcers, depression, heart disease, and many other illnesses.
For more information and examples, please see the article How Your Body Clock Regulates Your Metabolism.
Keeping Your Body Clock Running Smoothly
As a summary, the following guidelines can help to keep your circadian rhythm in its natural cycle:
- Use full-spectrum light bulbs in your home and office during daytime hours.
- Turn off computers and electronic gadgets once the sun sets, and avoid watching TV late at night. Again, the blue light emitted from TV's and computer screens mimic the blue light found in daytime sunlight, which can alter your melatonin production.
- Use "low blue lights" in areas where you spend most of your time in late evening, such as your living room, bedroom, and bathroom.
- Sleep in total darkness! If there is even the tiniest bit of light in your room it can disrupt your circadian rhythm and your pineal gland's production of the hormones melatonin and serotonin.
This is the "hidden" secret that most people tend to ignore, but which can dramatically improve the quality of your sleep. Personally, I sleep in a room that is so dark, it's even pitch black at noon. Liberally use blackout shades and drapes to achieve this.
- Sleep when it's dark outside and get up when the sun comes up. At minimum, strive to sleep between 10 p.m. and 6 a.m. This means you should be in bed, with the lights out, by 10 p.m. and be up by 6 a.m.
- Avoid working the night shift. It's been linked to significantly lower levels of serotonin, which may cause sleep problems, anger, depression and anxiety. If you currently work the night shift, I would strongly suggest trying to switch your hours, or at the very least not keeping the night shift for longer than a couple of months at a time (and giving your body a chance to readjust in between).
For even more helpful guidance on how to improve your sleep, please review my 33 Secrets to a Good Night's Sleep. If you're even slightly sleep deprived I encourage you to implement some of these tips tonight, as high-quality sleep is one of the most important factors in your health and quality of life.