A good night's sleep is one of the most critical factors in promoting good health and well-being. Learn about the melatonin half-life and how it affects the duration and potency of its sleep-promoting effects.
Unfortunately, obtaining a good night's sleep is easier said than done, which is why melatonin supplementation has grown in popularity.
Good quality sleep promotes both good mental and physical health and poor sleep quality can lead to depression, obesity, increased risk of diabetes and cardiovascular issues as well as lack of motivation.
Sleep deficiency is common in our society today.
Most of us can vividly recall a turbulent night of tossing and turning, the frustration that it results in, and the fatigue, grogginess, and irritability felt in the aftermath the following day.
Melatonin Half-Life For Quality Sleep
Different methods can be tried to help induce sleep quicker however, not everyone finds these compelling.
Aspects of our day-to-day lifestyle in the modern world, such as poor diet, lack of exercise, stress, and increased screen time, are all thought to be contributing factors to sleep deficiency.
Sleeping aids are increasingly common however, prescription medications come with risks of dependency and unwanted side effects therefore, many people have turned to natural supplements in an attempt to overcome sleep deficiency and improve their general health.
Some common natural sleeping aids include L-theanine, melatonin, lavender, and camomile.
The concern that often accompanies taking these supplements is that their effect will exceed the time required and leave us tired and groggy the next day.
This will be dependent on the half-life of the supplement.
Melatonin, in particular, has become increasingly popular in recent times as not only does it aid sleep deficiency, but its relatively short half-life means it is absorbed and eliminated quickly by the body, promoting quality sleep without a lingering effect.
This article will look at melatonin and its half-life in greater depth as we discuss what exactly melatonin is, how is it used, and most importantly how it helps obtain a sound night's sleep in relation to its half-life.
What Is Melatonin?
When we think of melatonin, it is often the OTC supplementary form that springs to mind first.
What we often don’t realize, is that we can get melatonin for free as it is a naturally occurring hormone produced by the body.
Melatonin is produced daily by the pineal gland in the brain as a response to decreasing light. It is often called the sleep hormone as it promotes sleepiness in individuals.
Melatonin works by regulating the circadian rhythm – an internal clock that alerts the body when it needs to sleep and when it needs to be awake over a 24hr period. (Source)
Under normal conditions, melatonin levels fall during the day as you are exposed to light.
The pineal gland signals the pineal gland to cease melatonin production.
The opposite then occurs when our exposure to light decreases.
As our surroundings get darker, the pineal gland increases the release of melatonin, and as the levels of melatonin rise, we begin to feel sleepier.
Even under normal conditions, some individuals do not produce sufficient melatonin.
Some causes of insufficient melatonin production include:
- Lack of exposure to natural light.
- Excessive blue light exposure.
- Aging.
- Shift working which interrupts the circadian rhythm.
- Alcohol intake and smoking.
This is where the role of OTC supplements comes into play.
Not only is supplemental melatonin used by those with reduced melatonin production, it is also commonly used to combat the effects of jet lag and insomnia.
How Long Does Melatonin Take To Work
The melatonin naturally produced by the body starts to increase about two hours before bed when darkness begins to fall.
This is usually around 9 pm.
If taken as a supplement, the effect will usually start to be felt within 30 -60 minutes, with studies showing it reaches its peak within 1-2 hours, however, a variety of factors can affect how long it takes melatonin to work. (Source)
Different forms of melatonin will be absorbed at different rates by the body.
The majority of melatonin supplements contain 3mg – 5mg.
Differing metabolisms can impact on the rate of absorption – some people find it best to start with a smaller and gradually increase in response to tolerance.
There are many different types of melatonin supplements readily available to buy OTC. It is readily available orally as a pill, liquid, gummy, or powder and in patch form. (Source)
Like other types of medications, melatonin absorption can be affected by the age and weight of the individual taking it.
As aging causes a drop in melatonin levels, it can often take longer to be effective in older people.
A higher body weight can also increase the time it takes to feel the effects of a melatonin supplement.
Another essential factor to consider that may affect the rate of melatonin absorption is other medications.
Blood pressure medications, as well as blood thinners and other anticoagulants, may not interact well with melatonin, and this should be discussed with your healthcare provider if there are concerns.
How Long Does Melatonin Last
When taking sleeping aids, one of the biggest concerns is how long they will be effective.
Although they are being taken to obtain a good night's sleep, we want to wake up feeling refreshed and energized, not still sleepy, because the supplement is still active in our system.
This is not something to worry about when taking melatonin and is one of the reasons why it is such a popular supplement.
Melatonin has a relatively short half-life – this refers to the time it takes to be processed, absorbed, and removed by the body.
The half-life of melatonin is said to be around 20-45 minutes.
This means if you took 3mg of melatonin at 9 pm, you would have 1.5mg in your system at around 10 pm and 0.75mg in your system by 11 pm.
In most cases, melatonin will be entirely eliminated by the body 4-5 hours after ingestion, meaning a quality night's sleep and no “hangover” effects of it the following morning.
Because of the short half-life of melatonin, you must time your dose well to ensure that it takes effect just before you go to bed.
The recommended time is usually 1–2 hours before you want to sleep.
Some supplement companies have developed extended-release melatonin, which is absorbed in a slower rate, which will therefore be effective for longer and can also give you a longer window in which it can be taken.
Extended-release melatonin may result in you still feeling tired when you wake up and make take longer to initially help you fall asleep therefore, an immediate-release supplement is best to induce sleep quicker and ensure you feel refreshed on awakening
Disruptions To Melatonin Effectiveness
As mentioned above, light exposure can impact melatonin levels.
Excessive blue light exposure, poor exposure to natural light, and some lifestyle factors can lead to lower levels of natural melatonin production in the body. (Source)
The effectiveness of melatonin supplements can also be affected by these. It is essential to practice good sleep hygiene and taking OTC melatonin to get the best results.
Ways to enhance the effectiveness of melatonin include:
- Reducing bright lights in the home in the hours leading up to bedtime and choosing dim lights instead.
- Aim to go to bed simultaneously every night to maintain a consistent body clock.
- Reduce your blue light exposure in the hours before by not using your phone or watching tv.
- Limit stimulants such as caffeine found in coffee and soda before bed.
Safe Use Of Melatonin
Generally speaking, melatonin supplements of 5mg or less are usually safe and tolerated by most people, although there is no official recommendation for the dosage.
Melatonin is generally considered safe to use however, as with all supplements it is possible to overdose, and it carries the risk of unwanted side effects. (Source)
Serious side effects of melatonin are rare, particularly compared to other sleep aids, however, in large quantities, supplemental melatonin can disrupt your natural circadian rhythm, and it also may cause unwanted side effects such as headaches, drowsiness, dizziness, and nausea.
Short-term melatonin use is considered safe in most adults, however, there is limited research on its long-term use and the effects it may have on our health.
Melatonin is not an addictive substance and people rarely become dependent on it, however, sleep experts have advised if taking nightly, to do so for one or two months at a time, and then a short break is recommended.
Melatonin should not be taken with other prescription sleep aids.
However, it is safe to take alongside supplements such as vitamin B6, L-theanine, and magnesium, which can have a calming effect on the body and support improved sleep quality.
It is not recommended to give melatonin supplements to children or infants who are struggling with insomnia and also not recommended for those pregnant or breastfeeding, who experience seizures, or have certain autoimmune conditions.
Melatonin supplements usually come with an expiration date and like many other supplements, tend to have a long shelf life.
These expiration dates often err on the side of caution, therefore, it is possible that if you take melatonin after its expiration date, it will have maintained its potency however it is recommended only to take supplements within their expiration date. (Source)
Melatonin Half-Life: Conclusion
Melatonin is a naturally occurring hormone that plays an integral role in obtaining good quality sleep.
It is commonly taken in supplementary form and is effective in people suffering from jet lag, or insomnia or who naturally produce less melatonin.
The short half-life of melatonin (20 -45 minutes) means that it is usually absorbed and eliminated by the body around 5-6 hours after ingestion.
Therefore it is safe to use without having to worry about it having a lingering effect the next day.
Melatonin is considered a safe supplement with minimal side effects however, there is limited research on the long-term effects of its use.