Just as many of us need "light therapy" in order to cope with SAD (Seasonal Affective Disorder), I would bet that many more of us actually need "dark therapy", and some of us probably could use a combination of both. In today’s world, we often don’t spend much time outdoors in the day, and we tend to live by artificial light at night.
Every cell of our body is sensitive to light and darkness, and now that we no longer tend to live according to the rising and setting sun, our health is suffering.
Melatonin, synthesized from the neurotransmitter serotonin and secreted by the pineal gland in the brain, is one of the victims of our current modern lifestyle. It has a big job to do – to help us recuperate from our day, and prepare us for tomorrow.
It is activated by darkness and inhibited by light, so before the invention of the light bulb when we actually lived according to the cycles of daylight and darkness, melatonin had adequate time to get its nightly job done. When it gets dark outside, it is supposed to be “melatonin time”.
Turning on the lights at night and staying up late tricks our body into thinking it is day, keeping the day hormone levels (like cortisol) higher. Then, when we finally go to bed and turn out the lights, melatonin may not have enough time to do its job before daybreak.
And if the bedroom is not completely dark – an outdoor street lamp is shining through the window onto our skin for example, melatonin may not be activated at all.
This is why working night-shift is so devastating to health. Many scientists believe that inadequate melatonin is a primary cause of many diseases like type 2 diabetes, heart disease and cancer, because then there is nothing to stop the run-away train that too much stress causes in the body.
The light of yang is no longer balanced by the dark of yin hormonally (cortisol / melatonin), in the CNS (sympathetic / parasympathetic), psychologically (stressed / relaxed) and even on a societal level (work / play). Work and productivity are valued highly in our society, whereas people that live a more balanced life are often considered "slackers" or lazy.
Melatonin is a very powerful antioxidant that works in watery as well as fatty environments, and unlike other antioxidants, melatonin is able to cross the blood brain barrier. So, at night, melatonin’s job is to sop up those free radicals before they do too much damage to other tissues.
Melatonin helps control the menstrual cycle in females, controls estrogen levels (thereby playing a key roll in preventing hormonal cancers like breast, ovarian, uterine and even prostate cancer), and is important in controlling circadian rhythms.
Melatonin is also synthesized by the immune system for its many roles within that system, including enhancing T cell production. Melatonin even seems to be involved in regenerating injured tissue, as seen in this study on rat degenerated intervertebral disks.
Melatonin, among other things, helps us sleep (or is supposed to!)
As someone who has a real problem sleeping, I completely disagree with the advice frequently given to insomniacs to get up, get out of the bedroom and read or do something if one can’t sleep because that would entail turning on a light, which would then shut down melatonin, resulting in less rest and repair happening.
Getting up certainly won’t help you get to sleep! I know from experience what putting in a full day of work feels like after lying in bed awake from 10pm to 7am, but turning on a light I think will just mess up the hormones more. You certainly don’t want to fire up cortisol at 2 in the morning!
Listening to relaxation CDs may be helpful. What helped me enormously when I wasn’t sleeping four out of seven nights for months on end, was listening to the relaxing Insight CD, which lowered my brain waves to delta, so even though I wasn’t sleeping, I was getting some rest. I honestly think that without that CD I would have had to cancel many a work day.
If you suffer from insomnia, it may be very tempting to rely on melatonin supplements to help you sleep. Personally, I think that apart from very occasional use to aid in jet-lag recovery, this is a bad idea because if you are providing external melatonin, your body will sense it in the blood stream and stop producing it.
Over time your pineal gland will shrink, and you may no longer be able to produce your own melatonin, which would leave you stuck taking the supplement for life. Far better to decrease sympathetic load (reduce your stressors), get lots of light during the day, and then lots of dark time at night.
Frequently addressing cortisol circadian-rhythm problems will also make a big difference, as high cortisol levels at night make it pretty hard to sleep! (Small aside, for those of you are keeping track – cortisol does not suppress melatonin, but melatonin does not suppress cortisol either.
That means you can have high cortisol levels when its dark and you are lying awake stressing, but melatonin is not active when it’s light. Therefore, cortisol is still the kingpin, as it is functional 24/7.)
In the winter time especially, our bodies probably need a good 9.5 hours in complete darkness. No light, TV sets, computers or night lights at all. Get that TV out of the bedroom!
That does not mean that we must be in bed sleeping for that length of time – dark time can provide an opportunity for meditation, contemplation or listening to music for example. This way it is easier to quiet the mind before trying to sleep.
If in the night you need to use the bathroom, don’t turn on the bathroom light. Use a red night light (not white, blue or green), or a flashlight with a red bulb.
Black-out drapes can make a huge difference to the darkness of a bedroom, or in a pinch you can put foil on the windows. Many people have said that they didn’t realize they were sleeping poorly until they slept in a completely darkened room.
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Copyright 2007 Vreni Gurd