The use of melatonin supplements has increased significantly in the United States in recent years, prompting calls for more research into the effects of long-term melatonin supplementation in humans.
This is because relatively little research has been done on how taking melatonin pills regularly affects overall health. Particularly in aging populations with Alzheimer’s disease or dementia. Melatonin support has also been recommended for blind people and struggle with a regular sleep schedule.
Synthetic versions of this hormone are frequently sold over the counter as a sleep aid, and research indicates that it likely has an impact on various aspects of health and well-being. The limited evidence available is also mixed on whether it benefits people who have trouble sleeping.
A search letter Posted in JAMA last year drew attention to an approximately five-fold increase in the number of people taking melatonin in the United States between 1999 and 2018. The findings of a team of researchers from Beijing and the Mayo Clinic in Rochester, in Minnesota, cited data from a national health and nutrition survey. . They called for more research on this topic in the scientific community.
Melatonin is a natural hormone produced by our brain, which generally increases when we are exposed to darkness (at night) and decreases during the day. Thus, it plays a dynamic role in the regulation of sleep and circadian rhythms in humans and other mammals.
Melatonin and sleep
The physiological production of this hormone usually declines in someone as they age, which could impact sleep patterns. This is where oral melatonin supplements show potential promise and have been prescribed for populations with dementia and those who have trouble sleeping.
But the precise way in which melatonin regulates sleep is not fully understood. For example, in its natural state, it does not have a sedative effect. Actually, in nocturnal animalsthe natural chemical is active and associated with states of wakefulness rather than sleep.
Learn more: The importance of sleep for your body
Other Uses of Melatonin
Beyond sleep, melatonin has also been shown to be a potent immune-modulating and antioxidant hormone, with properties that appear to lower blood pressure, positively regulate bone cell proliferation and inhibit bone resorption, according to a researcher. detailed review published earlier this year in Clinical Interventions on Aging.
Is melatonin safe?
Due to these many functions and some adverse effects of melatonin in limited trials, this opinion suggested that “melatonin should therefore be considered a drug, albeit a relatively safe one, rather than a harmless dietary supplement”.
The Mayo Clinic considers melatonin supplements as “generally safe” when treated as a sleeping pill and used under the supervision of a physician. But because the FDA defines the hormone as a dietary supplementthe product is poorly monitored and regulated in the United States, compared to over-the-counter and prescription drugs.
Melatonin and Alzheimer’s
Because aging and dementia often impact the sleep cycle in aging populations, some have turned to melatonin to help treat symptoms of Alzheimer’s disease and other life-threatening neurodegenerative diseases.
In this area too, the the results are mixed based on limited clinical trials. One of the main dilemmas is weighing the long-term effects and possible risks of taking melatonin supplements with the immediate potential benefits of managing symptoms, such as insomnia.
Learn more: There is a new drug approved by the FDA to treat Alzheimer’s disease
Long term side effects
“Some studies have found neuroprotective effects of melatonin itself, but there are also concerns about the long-term health consequences of melatonin,” says Yue Leng, an epidemiologist at the University of California, San Francisco.
Just this year, Leng published a study which compared the potential risk of dementia associated with various sleeping pills depending on the race of the participants.
This work indicated that frequent use of sleeping pills appears to be associated with an increased risk of dementia in older Caucasians. However, the scope of the research did not specifically identify associations between dementia risk and melatonin, due to the small sample of participants who reported using it.
“The effects of melatonin use on dementia risk is a controversial topic,” says Leng. “Further research is needed to examine the short- and long-term effects of melatonin on sleep and cognition in older adults.”
Learn more: Understand how dementia causes death
Does melatonin cause dementia?
In the same way, a 2016 Cochrane review identified a significant lack of evidence and research regarding sleeping pills for people with dementia.
Based on the limited trials that have been done, the researchers in this review found no evidence that melatonin has a significant impact – negative or beneficial – on people with dementia. They also found no significant improvement in sleep in those who took melatonin. But that was based on limited data, with just four trials at the time involving 222 participants.
Dementia and sleep
This same review found evidence to support the use of low dose trazodone (prescription medicine) to treat sleep problems in people with dementia, and no evidence of an effect of the sleeping pill ramelteon (prescription drug) on patients with mild to moderate disorders. Alzheimer’s dementia. This was also based on limited evidence.
The report ultimately concluded that much more research is needed in this area. “This is an area in dire need of pragmatic trials, especially for drugs commonly used clinically for sleep problems in dementia,” the researchers write. “Systematic evaluation of adverse effects is essential.”
Learn more: The 4 main types of dementia