Melatonin is often seen as a miracle sleep aid, but did you know that taking it can actually have negative consequences? Don't worry, I'll break it down for you in a way that won't put you to sleep.
First things first, let's talk about how melatonin works!
Melatonin is a natural hormone that is produced by the pineal gland in the brain and then released into the bloodstream. Darkness prompts the pineal gland to start producing more melatonin, which makes you sleepy, while light causes that production to stop, which wakes you up. As a result, melatonin helps regulate the circadian rhythm and synchronize the sleep-wake cycle with night and day. In doing so, it facilitates a transition to sleep and promotes consistent, quality rest.
So, what happens when you take melatonin supplements?
Well, for starters, melatonin supplements can help some people fall asleep more quickly and stay asleep longer. It is also used to treat a range of conditions, including sleep disorders, jet lag, and anxiety. But while it may seem harmless, there are some potential risks and side effects that you should be aware of:
1.Disrupts the natural sleep cycle and causes dependency
One of the main concerns with using melatonin supplements is that they can disrupt the natural sleep cycle. Research has shown that taking melatonin can interfere with the body's ability to produce its own melatonin, leading to a dependency on the supplement to fall asleep. This can result in a disrupted sleep cycle, with some individuals experiencing difficulty falling asleep or staying asleep without the use of melatonin. (5) In addition, some individuals may experience withdrawal symptoms when they stop using melatonin, including difficulty sleeping, anxiety, and irritability. (3)
Melatonin supplements can cause side effects in some individuals. These side effects can include dizziness, headaches, nausea, and drowsiness. In some cases, individuals have also reported feeling irritable or experiencing vivid dreams after taking melatonin supplements. (4)
3.Interference with other medications
Melatonin can interfere with other medications, including blood thinners, antidepressants, and antipsychotics. Research has shown that taking melatonin with these medications can increase the risk of side effects, including bleeding, mood changes, and heart rhythm disturbances. (2) Melatonin can also interfere with medications that are metabolized by the liver. A study published in the journal Clinical Pharmacokinetics found that melatonin can inhibit the metabolism of some medications, leading to higher levels of the drug in the body. (6)
Melatonin can have hormonal effects, particularly in women. Research has shown that melatonin can interfere with the menstrual cycle and may even cause premature menopause in some women. In addition, there is some evidence to suggest that melatonin can increase levels of prolactin, a hormone that is involved in milk production (1)
One of the most common side effects of melatonin is daytime sleepiness. This can be particularly problematic for people who work during the day or need to drive long distances. A study published in the journal Sleep Medicine found that participants who took melatonin experienced more daytime sleepiness and fatigue than those who did not. (5)
6.Impaired Cognitive Function
One of the most concerning negative consequences of melatonin use is impaired cognitive function. A study published in the journal Sleep found that healthy young adults who took melatonin supplements for five nights had significantly impaired cognitive function compared to those who took a placebo. The study concluded that "melatonin may have adverse effects on cognitive performance, especially in tasks that require sustained attention and working memory". (7)
While melatonin can be an effective sleep aid for some individuals, it is important to be aware of the potential negative consequences associated with its use, particularly in high doses or for an extended period of time. Individuals should consult with a healthcare provider before taking melatonin supplements, especially if they are taking other medications or have underlying health conditions.
1.Brzezinski, A. (1997). Melatonin in humans. New England Journal of Medicine, 336(3), 186-195.
2.Crespi, S., & Stepankiw, N. (2018). Melatonin. Treasure Island (FL): StatPearls Publishing.
3.Sack, R. L., Hughes, R. J., Edgar, D. M., et al. (1997). Sleep-promoting effects of melatonin: At what dose, in whom, under what conditions, and by what mechanisms?. Sleep, 20(10), 908-915.
4.Tordjman S, Chokron S, Delorme R, Charrier A, Bellissant E, Jaafari N, Fougerou C. (2017) Melatonin: Pharmacology, Functions and Therapeutic Benefits. Curr Neuropharmacol. Apr;15(3):434-443.
5.Zhdanova, I. V., Wurtman, R. J., Morabito, C., Piotrovska, V. R., & Lynch, H. J. (1995). Effects of low oral doses of melatonin, given 2-4 hours before habitual bedtime, on sleep in normal young humans. Sleep, 18(10), 847-855.
6.Jung, K. A., Lim, H. S., & Shin, K. H. (2011). Effects of melatonin on in vitro and in vivo P450-mediated drug metabolism and its potential clinical implications. Expert opinion on drug metabolism & toxicology, 7(6), 647-658.
7.Ferracioli-Oda, E., Qawasmi, A., & Bloch, M. H. (2013). Meta-analysis: melatonin for the treatment of primary sleep disorders. PloS one, 8(5), e63773.