Melatonin is a naturally occurring compound found in mammals, plants and microbes that in animals fluctuates on a daily cycle. In mammals melatonin is secreted into the blood stream by the pineal gland in the brain and is known as the “hormone of darkness.”
That is, melatonin is secreted in the middle of the night in both day-active (diurnal) and night-active (nocturnal) animals, including humans. Endogenous peak melatonin production occurs at 2 AM and ceases when the sun rises, making measurements of melatonin problematic. There are no foods that one can eat to raise melatonin levels, although it is synthesized in the brain from the essential amino acid L-Tryptophan.
Melatonin is available as an over-the-counter supplement and has been studied for the treatment of cancer, immune disorders, cardiovascular disease, depression, seasonal affective disorder (SAD), circadian rhythm and sleep disorders as well as sexual dysfunction and many other diseases and conditions. This is obviously a very large topic, so we will limit this discussion to melatonin’s antioxidant and sleep inducing effects, as well as how it prevents and may even help cure cancer.
Many years ago I was attending a bioidentical hormone conference where the speaker presented the case of a 20 y/o woman who had developed bilateral breast cancer. That is very unusual of course, and in the process of a complete diagnostic work-up, it was found that her pineal gland was completely calcified, essentially a piece of stone in the middle of her brain. Since the pineal gland is where melatonin is produced, this meant she had no melatonin whatsoever.
This indicates melatonin has very potent anti-cancer effects and when absent markedly increases cancer risk, especially breast cancer.
The World Health Organization has named late night shift work as a probable cancer provoking activity. Reduced melatonin production has been proposed as a likely factor in the significantly higher cancer rates observed in night workers.
Melatonin is a very powerful antioxidant that can easily cross the cell membrane and blood brain barrier. It is a direct free radical scavenger of hydroxide, oxygen and nitrous oxide free radicals. Unlike vitamin C that can be “recycled” which allows it to also be a pro-oxidant, melatonin is reduced to several stable endpoints upon reacting with free radicals, meaning it is a terminal (or suicidal) antioxidant.
Recent studies of melatonin metabolites show it can neutralize up to 10 reactive oxygen or nitrogen species. This makes melatonin capable of creating a “free radical scavenging cascade” that is not possible with other antioxidants. In animal models this superior antioxidant ability can prevent damage to DNA by some carcinogens.
Melatonin’s antioxidant activity may reduce cellular damage such as in Parkinson’s, as well as prevent cardiac arrhythmia and possibly increase longevity.
The average life span of mice has been increased by 20% with melatonin. Another way in which melatonin may prevent cancer is its radiation protecting effects. Melatonin protects against ionizing radiation via free radical scavenging of the hydroxyl free radical that attacks DNA, proteins and cellular membranes. A systematic review of unblinded clinical studies involving a total of 643 cancer patients using melatonin documented a reduced incidence of death.
Melatonin may have exceptional anti-aging effects as well. Young children hit their peak melatonin production at night. As we age, the peak melatonin production occurs earlier at night, which may explain why adults go to bed earlier, wake up earlier and have more sleep difficulties.
Another study has found melatonin is crucial to slowing the aging process via its effects on specific genes. The administration of melatonin may reverse the gene expression of over 100 genes, making the genes of elderly people similar to those of younger people. Thus, using melatonin supplements may assist in reversing some signs and symptoms of aging by working at a genetic level, influencing the aging process favorably.
Poor sleep is a symptom that plagues millions of men and women. The melatonin signal forms part of the system that regulates the wake-sleep cycle by chemically causing drowsiness and lowering body temperature. Human melatonin production decreases as a person ages. In humans, 90% of melatonin is cleared in a single pass through the liver. This is why those who use melatonin supplements to improve the length and depth of sleep may not find success, as over-the-counter melatonin supplements create a rapid blood spike that is rapidly washed out.
Using a compounded, slow release version with a higher dose (3 – 20 mg) may be a better option that will create a more sustained blood melatonin level. A prolonged release prescription version of melatonin called “Circadin” has been approved in Europe for patients over age 55 for the treatment of insomnia.
Melatonin is remarkably safe with few side effects.
Next day grogginess, irritability, vivid dreams and/or nightmares and hypothermia have occurred in some people with doses over 3 mg taken at bedtime. Toxicity has not been seen in doses as high as 200 mg/kg bodyweight in mice.
In summary, melatonin is a very safe and potentially very effective hormone treatment for improving sleep, treating jet lag and insomnia that has minimal downside. It may help prevent a number of cancers as well as slow down the aging process.
Even children with autism have been documented to fall asleep faster and longer with nightly doses of 2-10 mg of melatonin.
Other studies have found melatonin may relieve headaches, reduce delirium, and improve mood disorders such as SAD, bipolar disorder and some forms of depression. Vivid dreaming indicates melatonin is increasing REM restorative sleep.
Randy Ice and David Mitzner are with Vintage Medical Group.
This article contains information provided by Randy Ice, PT, CCS and David Mitzner, DO.