Melatonin, commonly known as the sleep hormone, is a natural hormone produced by the pineal gland and bacteria in the gut that plays various roles throughout the body, including affecting circadian rhythm, sleep, and immune health.
Melatonin is involved in numerous aspects of the biological and physiological regulation of body functions. It helps promote total sleep time, aids with fatigue from jet lag, balances circadian rhythms, and helps rest the body’s sleep/wake cycle.
When you produce melatonin is just as important, if not more so, then the total amount that gets produced. Ideally, we want higher levels at night (beginning around 9 p.m.) and lower levels in the morning. When the sun goes down and the day begins to get darker, the pineal gland is activated by the suprachiasmatic nucleus (SCN), and begins to produce melatonin, which is then released into the blood.
As melatonin levels rise in the blood, we begin to feel sleepy and tired. Melatonin levels can stay elevated in the body for roughly 12 hours, and they should remain elevated through the entire night, as well as before light from the new day arrives. Melatonin levels should fall back to lower levels during the daytime by about 9 a.m., and daytime levels should be barely detectable. When melatonin levels remain too high during the day, it can be difficult getting started in the morning and can lead to feelings of sluggishness or fatigue all day.
The gastrointestinal tract contributes significantly to circulating concentrations of melatonin, especially during the daytime. Melatonin acts as an endocrine hormone throughout the body, influencing the function and regeneration of the epithelium, as well as enhancing the immune system of the gut and overall body.
Melatonin levels are directly influenced by a number of factors, and our lifestyle and sleep habits can be a big part of that. Factors that can lead to low melatonin include:
Lack of sleep
Lack of natural light exposure
Time zone changes or frequent traveling
Bacterial imbalance in gut
When melatonin levels become depleted, symptoms can include fatigue sickness, agitation, depression, anxiety, and other mood disorders.
Melatonin is clearly important, but what specifically can it do for your body when you have optimum levels?
Roughly 70 million Americans suffer from a disorder of sleep and wakefulness that hinders their ability to function each day, but also jeopardizes health and longevity. Long term sleep deprivation can lead to diabetes, obesity, depression, heart attack, and stroke.
Melatonin can shorten time it takes to fall asleep, increase total sleep time, and even improve sleep quality and morning alertness.
Travel can lower melatonin levels. The American Academy of Sleep Medicine has found that using melatonin reduces jet lag symptoms and improves sleep after traveling across more than one time zone.
The antioxidant role of melatonin has been used for a variety of conditions in which oxidative stress is involved. The immune-enhancing effects of melatonin appear to be an integral immune-recovery mechanism with melatonin acting as a buffer against the harmful effects of stress on immune balance. Immune modulating effects of melatonin can slow or prevent the inflammatory response in the body.
A close relationship exists between pineal gland in the brain and the pituitary/adrenal axis. Melatonin modulates the activity of this axis and the actions of steroid hormones that deal with the sympathetic nervous system.
Melatonin can also reduce overall stress hormone levels, and some research shows that it can even help improve depression. Chronically elevated levels of cortisol have been linked to several aspects of aging and age-associated problems like glucose intolerance, and impaired immune function.Melatonin can act as an anti-stress factor in the body, helping provide potential balance for all of these areas.
The link between melatonin levels, pineal function, and mood disorders is seen in those who have both seasonal affective disorder and class “non seasonal” depression. Research has found that nocturnal melatonin levels are low in those who suffer from major depressive disorder and panic disorder. This is seen most specifically in individuals who have abnormal pituitary-adrenal responses to excessive cortisol levels.
Brain serotonin levels have been shown to increase after melatonin supplementation, which is significant because serotonin has been linked with mood support, reduced anxiety, relieved insomnia, and improved impulse control.
Ways to Increase Melatonin Levels
Supplemental forms of melatonin can be taken to increase blood levels. Certain foods contain melatonin and can be eaten at dinner to help with sleep. Try bananas, beets, cucumbers, pineapples, oranges and tomatoes.
Sleeping in complete darkness can also help melatonin levels. Light from electronic devices disrupts your body’s natural circadian rhythm, causing your serotonin and melatonin production to decrease. Even the tiniest bit of light can disrupt your sleep.
Source: Vitamin Retailer, February 2019