Sleep problems are a common issue in the Western world, with millions of people suffering from sleep disorders such as insomnia. Lack of sleep not only affects our daily productivity but can also have long-term health consequences such as weight gain, diabetes, and cardiovascular disease (1). To combat these problems, many people turn to synthetic sleeping pills, which can be highly addictive and often have unwanted side effects. However, natural supplements such as melatonin are increasingly being seen as a healthy and effective alternative to these synthetic drugs.
What is Melatonin?
Melatonin is a hormone produced by the pineal gland, a small gland in the brain, which helps regulate the sleep-wake cycle. It is involved in the timing of the body's biological clock and plays a key role in promoting restful sleep. Melatonin levels rise in the evening, signaling the body to prepare for sleep, and decrease in the morning, signaling the body to wake up (2). Melatonin is available in supplement form and is commonly used as a sleep aid to help people fall asleep more easily and improve the quality of their sleep.
The pineal gland is also involved in other physiological functions, such as the regulation of the immune system, the production of certain neurotransmitters, and the modulation of reproductive hormones. In additions, the pineal gland has also been associated with spiritual and metaphysical experiences, and is sometimes referred to as the "third eye" in certain cultures and spiritual traditions. While there’s no scientific evidence for any spiritual claims, the mere fact the same pineal gland that produces melatonin is considered somewhat “holy” (7) in these cultures suggests the knowledge of Melatonin and its benefits for the human sleep cycle are older than we thought!
The most common types of melatonin Immediate-release melatonin: This type of melatonin is designed to be quickly absorbed by the body and is intended to help people fall asleep more quickly. Extended-release melatonin: This type of melatonin is designed to release melatonin gradually over a longer period of time, which can help people stay asleep throughout the night. Sublingual melatonin: This type of melatonin is placed under the tongue and absorbed through the mucous membranes, allowing for faster absorption and more rapid onset of sleep. Topical melatonin: As the name implies, this variation of melatonin is applied to the skin where the melatonin gets absorbed through
Importance of melatonin for sleep
One of the key reasons that melatonin is so important for sleep is that it plays a critical role in regulating our circadian rhythms, which are the natural biological cycles that govern our sleep and wakefulness. When our circadian rhythms are disrupted, either through external factors such as exposure to artificial light (3) at night or internal factors such as hormonal imbalances, it can be difficult to fall asleep and stay asleep.
However, you can still fall asleep without any melatonin in your system! While it indeed plays an important role in regulating the body's sleep-wake cycle, it is not the only factor that affects our ability to fall asleep and stay asleep (4). Other factors that can impact our sleep quality include environmental factors such as noise, light, and temperature, as well as lifestyle habits such as caffeine intake, alcohol consumption, and exercise habits.
How does Melatonin work?
Explanation of the sleep-wake cycle
The sleep-wake cycle is a natural biological process that regulates when we feel sleepy and when we feel awake. It is controlled by the circadian rhythm, which is a 24-hour cycle that is influenced by external factors such as light and darkness. During the day, our bodies produce hormones like cortisol that keep us alert (5) and awake, while at night, our bodies produce melatonin that signal to the body that it's time to sleep.
Role of Melatonin in regulating sleep
Melatonin is a hormone produced by the pineal gland in the brain that helps to regulate the sleep-wake cycle. Melatonin levels increase in the evening and remain elevated throughout the night, signaling to the body (8) that it's time to sleep. Melatonin also helps to regulate the duration and quality of sleep, and has been shown to be helpful for individuals with sleep disorders such as insomnia or jet lag.
Melatonin production and release
Melatonin production is also influenced by external factors such as exposure to light. During the day, the pineal gland produces very little melatonin, but as the evening approaches and darkness falls, melatonin production increases (6). Melatonin is released into the bloodstream and helps to signal to the body that it's time to sleep. Factors such as age, shift work, and exposure to artificial light at night can all impact melatonin production and release.
Factors affecting Melatonin's efficacy
Age and weight of the person
As we age, our bodies produce less melatonin, which can make it harder to fall asleep and stay asleep. This is why older adults are more likely to experience sleep disturbances and insomnia. Additionally, the efficacy of melatonin supplements may be impacted by a person's weight. Higher doses of melatonin may be needed for individuals who are overweight or obese, as melatonin is stored in fat cells and may be less available for use by the body.
Dose and form of Melatonin
The effectiveness of melatonin supplements can also be impacted by the dose and form in which it is taken. For example, immediate-release formulations may be more effective for individuals who have difficulty falling asleep, while extended-release formulations may be more effective for individuals who have difficulty staying asleep. Additionally, higher doses of melatonin may not necessarily be more effective, and can actually lead to adverse effects such as daytime drowsiness and headaches.
Other medications and health conditions
The efficacy of melatonin supplements can also be impacted by other medications and health conditions. Certain medications, such as beta blockers and blood thinners, can interact with melatonin and decrease its effectiveness. Additionally, individuals with certain health conditions, such as liver disease, may not be able to effectively metabolize melatonin, which can impact its efficacy.
Precautions and potential melatonin side effects
Morning cortisol signals melatonin release for sleep later. 12-14 hours after the cortisol gets released, the melatonin will. This means your waking time and your earliest exposure to sunlight play an important role on when your body starts feeling ready for sleep in the evening. If you’re messing around with melatonin during the wrong times, overdose etc. your whole rhythm therefore might become distracted.
Furthermore, melatonin heavily affects your hormone system! Studies with seasonally breeding animals injected with melatonin resulted in significant shrinkage of their gonads which shrank from a healthy size to the size of a grain of rice… and since melatonin can suppress hormones needed for puberty onset, it should not been given to kids or teenagers!
Last but not least, melatonin supplements may help fall asleep but not stay asleep. Even more so if the real dosage differs from the label: Commercially available melatonin may only contain 15% of the amount listed on the bottle!
So how long does it take for Melatonin to work?
The timeline for when melatonin takes effect can vary depending on factors such as the form and dose of the supplement, as well as the individual's age, weight, and overall health. For adults, the usual dosage is between 1 and 10 milligrams per day, taken one to two hours before bedtime. It is recommended to start with a lower dose and gradually increase it until the desired effect is achieved.
The best time to take melatonin is 30 minutes to two hours before bedtime, while some people report best effects with 3-5 hours before. If you’re not sure when to take your melatonin, just start with 1 hour before bedtime and gradually increase the time until you find your perfect spot. It's important here to note that melatonin is not a sedative and does not induce sleep on its own, but rather helps to regulate the body's sleep-wake cycle. It may take a few days or weeks of consistent use for the effects of melatonin to be fully noticeable.
References
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6473877/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4334454/
- https://febs.onlinelibrary.wiley.com/doi/abs/10.1111/j.1742-4658.2006.05322.x
- https://www.nature.com/articles/emm2014121
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3654533/
- https://link.springer.com/article/10.1007/BF01923947
- https://journals.sagepub.com/doi/pdf/10.1177/074873048700200404
- https://www.sciencedirect.com/science/article/pii/S1087079208000786
- https://bpspubs.onlinelibrary.wiley.com/doi/abs/10.1111/bph.14116
