Melatonin is a hormone produced in the pineal gland in response to light therefore, among many things, it regulates the sleep-wake cycle or circadian rhythm and is also a very powerful antioxidant. The pineal gland is a pea-sized gland located just above the middle of the brain. During the day the pineal is inactive. When the sun goes down and darkness occurs, the pineal is “turned on” and begins to actively produce melatonin, which is released into the blood. Usually, this occurs around 9 pm. As a result, melatonin levels in the blood rise sharply and you begin to feel less alert. Sleep becomes more inviting. Melatonin levels in the blood stay elevated for about 12 hours – all through the night – before the light of a new day when they fall back to low daytime levels by about 9 am. Daytime levels of melatonin are barely detectable.
Urinary 6-Sulfatoxymelatonin (MT6s) is the main metabolite of melatonin. MT6s itself has no physiologic activity, but testing it in the urine is a good indicator of whole body melatonin production. Low urinary MT6s is an indication for melatonin supplementation. It is normal to see elevated urinary values with supplemented doses higher than 1mg.
Studies have shown that monitoring this metabolite in the urine collected upon waking correlates to the night’s production of melatonin.
Low levels:
Melatonin is important because it is a potent antioxidant, immune system modulator, promoter of growth hormone production and can improve those affected by seasonal affective disorder (SAD). Therefore, low levels of melatonin can cause sleep issues (falling or staying asleep), weaker immune systems, mood changes, fatigue, and low growth hormone.
When the melatonin level is too low it might lead to sleeping problems and consequently lack of sleep and tiredness. This has a negative effect on the general well-being. Sleep disturbances depending on a lack of melatonin especially express with problems to fall asleep and early awakening. The resulting missing and therefore not very restful sleep can cause susceptibility to diseases, concentration disturbances, poor memory, mood swings etc.
Since the melatonin production constantly decreases in the course of life older people are more concerned by this. But due to our modern lifestyle and certain factors from the outside, many people often suffer under a lack of melatonin. Influencing factors might be
- long phases of daylight in summer, long phases of artificial light due to electric light, computer and TV
- lack of serotonin
- intake of certain medications like for example beta blockers
- consumption of caffeine, alcohol or tobacco
- too intensive sport too late in the evening
- ongoing stress
In addition, high stress, particularly elevated cortisol at night, is suppressive to the pineal gland causing lower levels of melatonin.
Try to spend as much time as possible in natural day light and eat tryptophan-containing foods (ex. spinach, seeds, nuts).
High levels:
Slightly elevated levels of melatonin may be due to the supplements tryptophan or 5HTP (as both promote serotonin and serotonin can convert into melatonin) and SSRI’s (particularly fluoxetine) or MAO inhibiting medications.
An increased melatonin level, too, is noticeable by sleep disturbances and tiredness. An increased melatonin level makes waking up in the morning difficult. During the day, you are feeling lethargic. Especially in the colder and darker months of autumn and winter the melatonin production is increased. This also might lead to seasonal affective disorder (SAD).
A too high melatonin level can be caused by:
- long phases of darkness in the winter
- liver dysfunction
- high intake of vitamins B3 or B6
- intake of tryptophan or certain antidepressants
Here, daylight is helpful. And – as soon as the days start to get longer, the symptoms might decrease.
Disclaimer:
The information on healthmatters.io is NOT intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice.
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