Check out this answer from Consensus:
Overall, the majority of research supports the use of melatonin as an effective treatment for reducing jet lag symptoms, particularly for flights crossing five or more time zones. The timing of administration is crucial, and doses between 0.5 and 5 mg are recommended. While melatonin is generally safe for short-term use, further studies are needed to explore its long-term safety and efficacy, especially in individuals with specific health conditions.
Jet lag is a common issue faced by travelers who cross multiple time zones. It results from the body’s internal clock being out of sync with the new local time, leading to symptoms such as fatigue, insomnia, and reduced cognitive function. Melatonin, a hormone produced by the pineal gland, has been widely studied for its potential to alleviate these symptoms by helping to regulate the body’s circadian rhythms. This article explores the effectiveness of melatonin in preventing and treating jet lag based on current research.
Mechanism of Action
Melatonin plays a crucial role in regulating sleep-wake cycles. It is naturally produced in response to darkness and helps signal to the body that it is time to sleep. By taking melatonin supplements, travelers can potentially reset their internal clocks to align with the new time zone, thereby reducing the symptoms of jet lag1 2 3.
Effectiveness of Melatonin
Several studies have investigated the effectiveness of melatonin in alleviating jet lag. A comprehensive review of randomized trials found that melatonin, taken close to the target bedtime at the destination (10 pm to midnight), significantly decreased jet lag symptoms for flights crossing five or more time zones. Daily doses between 0.5 and 5 mg were found to be similarly effective, although higher doses (5 mg) helped individuals fall asleep faster and sleep better1 2 3.
Another study confirmed these findings, showing that melatonin significantly improved global treatment efficacy, morning fatigue, and evening sleepiness when taken at the appropriate time5. However, it is important to note that the timing of melatonin administration is crucial; taking it at the wrong time can cause sleepiness and delay adaptation to the local time1 2.
Dosage and Administration
The optimal dosage of melatonin for jet lag appears to be between 0.5 and 5 mg. Higher doses do not seem to offer additional benefits and may increase the risk of side effects. Slow-release formulations are less effective than immediate-release forms, suggesting that a short-lived higher peak concentration of melatonin is more beneficial1 2 3.
Safety and Side Effects
Melatonin is generally considered safe for short-term use. The incidence of side effects is low, but some individuals may experience sleepiness if melatonin is taken at the wrong time. There are also concerns about its use in people with epilepsy and those taking warfarin, as melatonin may interact with these conditions and medications1 2 3.
Conflicting Evidence
While many studies support the use of melatonin for jet lag, some research has shown mixed results. For example, a study involving Norwegian physicians found no significant differences in jet lag symptoms between those taking melatonin and those taking a placebo4. Another study suggested that melatonin had no significant benefit in alleviating jet lag symptoms for travelers who maintained a busy and erratic schedule6.
Does melatonin help jet lag?
Peter Fowler has answered Likely
An expert from Aspetar Orthopaedic and Sports Medicine Hospital in Sleep Research, Sports Science
The plain language summary from a Cochrane systematic review and meta-analysis (a very robust assessment of the current evidence available) published in 2002 on ‘Melatonin for the prevention and treatment of jet-lag’ was… “Melatonin is effective in preventing or reducing jet lag, and occasional short-term use appears to be safe. It should be recommended to adult travelers flying across five or more time zones, particularly in an easterly direction, and especially if they have experienced jet lag on previous journeys. Travelers crossing 2-4 time zones can also use it if need be.”
However, as Amy alluded to in her response, for utilising melatonin to treat jet-lag and thus, for its chronobiotic (adjusting the body clock) rather than it’s soporific (sleep-inducing) properties – a.) the timing of intake is important and b.) the timing of light exposure is also important – if either of these are incorrect then the body clock could shift in the wrong direction and make jet-lag symptoms worse.
For this specific example – travel across 8 time-zones WEST from London to Los Angeles – a phase delay in the body clock is required. Thus, based on the literature, the following would be recommended… Technical jargon i.) exposure to bright light in the 3-4 h before the daily minimum in body temperature (Tmin), which occurs around 04:00 for people who are in bed from 23:00 – 07:00 (ii) avoiding light in the 3-4 h after Tmin, and (iii) taking melatonin ~4 h after Tmin (being mindful of its soporific effects) Layman’s terms On day 1, your Tmin would occur around 20:00 LA time. Therefore, maximise bright light exposure from 17:00 – 20:00 and avoid light exposure from 20:00 – 23:00. In this case melatonin could be taken around bed time (approx. 22:00) for both its chronobiotic and soporific properties.
However, it is worth bearing in mind that there will be instances where melatonin shouldn’t be used… a.) The timing of intake for its chronobiotic properties doesn’t correspond to evening time in the new location. b.) Intake in the evening for its soporific properties corresponds to the wrong time for its chronobiotic properties (i.e. it would cause your body clock to shift in the wrong direction).
Therefore, in conclusion to the question ‘Does melatonin help jet-lag?’ my answer would be likely BUT it depends on the specific travel scenario.
Does melatonin help jet lag?
Diego Golombek has answered Near Certain
An expert from Consejo Nacional de Investigaciones Científicas y Tecnicas in Neuroscience, Medicine
Melatonin is a hormone secreted by the pineal gland which, in most species, represents a nocturnal code. In addition, seasonal species might use melatonin as a biological calendar, differentially coding long winter or short summer nights.
In mammals, including humans, melatonin secretion is controlled by a master biological clock located in the hypothalamus (the suprachiasmatic nuclei, or SCN) which uses this hormone to signal the absence of light to the rest of the body (in Game of Thrones lexicon “the night is here”).
The pharmaceutical industry has taken advantage of this property and synthesized melatonin to be used a chronobiotic (i.e., a drug that moves the hands of the biological clock). It is important to state that melatonin is not a hypnotic drug – it won’t make you sleep unless taken in relatively high doses. As a chronobiotic, melatonin should be taken in the evening in order to strengthten the “night” signal of the clock. A 1-3 mg dose of Melatonin has been demonstrated to aid in the treatment of sleep problems.
Jet-lag occurs when, after crossing several time zones, the external time is different from the internal hours. While melatonin has very specific time-dependent effects (defined by what is called the “phase response curve” of the drug) a relatively simple rule would be to take the hormone even before the flight (1-2 days) at the evening (let’s say 10 pm) time in your destination, and continue taking it during the flight and for a few days after arrival.
Complementing melatonin with a correct exposure to natural light (in the morning after eastward flights, in the afternoon after westward flights) could alleviate some of the symptoms of jetlag.
Does melatonin help jet lag?
Amy Bender has answered Near Certain
An expert from Centre for Sleep & Human Performance in Sleep Research
Melatonin has been shown to be an effective chronobiotic, meaning it helps shift circadian rhythms. Studies have shown a dose of about 0.5 mg is effective at shifting your circadian rhythms, however a higher dose of 1-3 mg may give you the added benefit to help you fall asleep.
You have to be careful though with the brand you are using. One study published last year which looked at 30 different products found the content of melatonin ranged from -83% to +478% of the content label with only 29% of the products within 10% of the label. Best to get a trusted pharmaceutical grade.
In the case of heading West from London to LA, you will want to prepare ahead of the trip (~3 days before) by shifting your sleep times later (go to bed later and get up later), getting light late right before bedtime (using a light box for 20 min or turning up the lights 2h before bedtime), and blocking light in the morning for the first 2h of waking by wearing dark sunglasses and avoiding going outside. Melatonin in this instance is not very useful when travelling west. It may help for you take it once you get there about 2-3h before bedtime.
Does melatonin help jet lag?
Chris Milne has answered Likely
An expert from Anglesea Medical in Sports Science, Medicine
In my opinion, the evidence is mixed. No single strategy is effective for everyone. There is a spectrum of expert opinion on the effectiveness of melatonin. Certainly, the action is biologically plausible, and there does seem to be a dose response – ie within the therapeutic range, a higher dose will often be more effective.
Does melatonin help jet lag?
John Axelsson has answered Near Certain
An expert from Karolinska Institutet in Sleep Research, Cognitive Science, Psychology, Immunology
Melatonin is a chronobiotic that can be used to alter a persons circadian rhythm, and hence speed up (or disturb) the adaptation of a persons rhythms to a new time zone. While exposure to light and melatonin give information of daylight and night, it is likely that also cortisol and feed timing can be used to alleviate jetlag. The timing is, however, crucial for whether these aspects will help reduce jetlag or make it worse.