Jet lag is a common challenge for travellers, caused by disruptions to the body’s natural sleep-wake cycle when quickly crossing time zones. It affects people of all ages and can make adjusting to new environments more difficult.
Managing jet lag effectively can significantly improve your travel experience by reducing symptoms like fatigue, poor concentration and digestive discomfort.
This guide offers practical, scientifically backed advice on how melatonin can help manage its effects, providing answers to some of the common questions, including how melatonin works and the best ways to help your body adjust to a new time zone.
What are the symptoms of jet lag?
According to the NHS, some of the most common symptoms of jet lag include:
- Fatigue
- Difficulty sleeping at night (insomnia)
- Poor concentration or difficulty focusing
- Feeling disoriented or confused
- Digestive issues such as constipation or diarrhoea
- Mood changes, including irritability or mild depression
- General malaise or a sense of not feeling well
- Headaches
Recommended reading: How to Beat Jet Lag
How does melatonin work to prevent jet lag?
Melatonin is a hormone naturally produced by the pineal gland that plays a crucial role in regulating the body’s sleep-wake cycle, or circadian rhythm.
This internal clock, controlled by the brain’s suprachiasmatic nucleus (SCN), responds to changes in light and darkness to maintain a healthy sleep schedule. Normally, the SCN triggers the release of melatonin in the evening, promoting drowsiness and preparing the body for sleep.
When you travel across time zones, the circadian rhythm can become out of sync with the local time, leading to jet lag symptoms such as insomnia and fatigue.
Taking melatonin supplements close to your target bedtime at the destination helps mimic the body’s natural hormone production, signalling to your brain that it’s time to rest.
This not only promotes sleep but also aligns your circadian rhythm with the new light-dark cycle of your destination. Furthermore, melatonin interacts with receptors in the brain that regulate sleep timing, enhancing its ability to prevent jet lag symptoms.
Recommended: Watch our Video Guide to Melatonin (Jet Lag Treatment)
How effective is melatonin at preventing jet lag?
Melatonin is a proven and effective solution for preventing jet lag, working through two primary mechanisms that target its underlying causes.
Taking melatonin supplements close to your target bedtime at the destination, typically between 8 pm and midnight, helps signal to the SCN that it is nighttime. This mimics the natural release of melatonin from the pineal gland, aligning your body’s internal clock with the new time zone.
Melatonin also interacts with specific receptors in the brain, known as MT1 and MT2, which regulate the timing of the circadian rhythm. These receptors help align the body’s internal clock with the new light-dark cycle, reducing the severity and duration of jet lag. Taking melatonin supplements can promote sleep and support a smoother transition to the new time zone.
Research shows that melatonin is particularly effective for travellers crossing five or more time zones, where jet lag symptoms such as insomnia, fatigue and disorientation are most pronounced. However, it is important to consult a healthcare professional before using melatonin to ensure it is appropriate for your specific needs and travel plans.
When should I take melatonin to avoid jet lag?
The general recommendation is to take melatonin at your destination's local bedtime in the evening, which helps align your body's internal clock with the new time zone. Here are some practical guidelines:
Westward Travel
If you're travelling west and your destination's local bedtime is earlier than your body's internal clock, take melatonin an hour or two before your planned bedtime at the destination. This helps you fall asleep earlier.
Eastward Travel
If you're travelling east and your destination's bedtime is later than your internal clock, take melatonin in the evening at your destination to delay sleep onset and match the local schedule.
Recommended: Watch our Video Guide on How to Avoid Jet Lag
How long does melatonin take to work?
Melatonin typically starts to work within 20 to 60 minutes after taking it. This can vary depending on factors such as the dosage and individual differences in metabolism.
For optimal results in managing jet lag, take melatonin 30 to 60 minutes before your target bedtime at your destination. This timing helps align the body’s internal clock with the local time, promoting sleepiness at the appropriate hour.
What is the best way to use melatonin safely?
Melatonin can be an effective tool for managing jet lag, but using it safely and correctly is essential for the best results. Follow these guidelines to ensure safe and effective use:
Ensure correct timing
Take melatonin close to your target bedtime at your destination, usually between 8 pm and 4 am, depending on your new time zone. This timing helps align your internal body clock with the local time at your destination. Start using melatonin on the day you travel, and continue for a few days after arrival to support your body in adapting to the new schedule.
Avoid Overuse
Melatonin is designed for short-term use and should not be taken for more than 5 consecutive days unless advised by a healthcare provider. Overuse can disrupt your natural sleep-wake cycle and reduce the effectiveness of melatonin over time, making it harder for your body to regulate sleep naturally.
Combine with light exposure
Using melatonin alongside strategic light exposure can significantly improve its effectiveness in resetting your internal clock. In the morning, seek natural sunlight at your destination to signal your body to wake up and adjust to the local time. Avoid exposure to bright artificial lights in the evening, as this can interfere with the body's natural melatonin production and disrupt your sleep schedule.
Ensure sufficient sleep
Only take melatonin when you have at least 7–8 hours available for sleep to prevent lingering drowsiness or fatigue the next day. Taking melatonin without allowing enough time for rest may impair your focus and energy levels during the day.
Avoid alcohol
Do not consume alcohol while taking melatonin, as it can interfere with its absorption and effectiveness. Alcohol may also disrupt sleep quality and amplify side effects such as dizziness or drowsiness, counteracting the benefits of melatonin for jet lag.
Avoid interactions
Melatonin may interact with certain medications, including blood thinners, sedatives or immune-suppressing drugs, potentially altering their effects or increasing the risk of side effects. If you are taking any of these medications, consult your doctor before using melatonin to ensure it is safe for you and will not interfere with your treatment.
Seek medical advice if pregnant or breastfeeding
Pregnant and breastfeeding individuals should consult a healthcare professional before using melatonin, as there is limited research on its safety during pregnancy and lactation.
Where can I buy melatonin?
Melatonin can be bought from Pharmica, which offers fast delivery across the UK. We provide treatments sourced from MHRA-approved suppliers and offer a wide range of aftercare services, including comprehensive guides on the Pharmica Health Hub, live chat support with our pharmacy team, and more.
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Summary
Using melatonin effectively to manage jet lag involves understanding how it supports the body’s natural sleep-wake cycle. Jet lag occurs when crossing time zones disrupts this cycle, leading to fatigue, insomnia and difficulty adjusting to new schedules. Taking melatonin at the right time and following essential guidelines can minimise these symptoms and improve your transition to a new time zone.
To optimise the effectiveness of melatonin for managing jet lag, it is important to consider factors that influence how your body responds to the supplement. Combining melatonin with strategies such as reducing evening light exposure, avoiding alcohol and establishing a consistent bedtime routine at your destination can enhance its effectiveness and support a smoother adjustment to the new time zone.
At Pharmica, we offer a wide range of clinically proven treatments designed to help manage jet lag and support smoother transitions across time zones. With a 4.9/5 rating from over 196,000 reviews, we have supported the health journeys of more than 1.45 million customers.
- Herxheimer & Petrie (2002). Melatonin for the prevention and treatment of jet lag. Cochrane Database of Systematic Reviews, 2, CD001520. doi: https://doi.org/10.1002/14651858.CD001520. [Accessed: 19 November 2024].
- Arendt et al. (1997). Efficacy of melatonin treatment in jet lag, shift work, and blindness. Journal of Biological Rhythms, 12 (6), pp. 604-617. doi: 10.1177/074873049701200616.
- Cingi et al. (2018). Jetlag related sleep problems and their management: A review. Travel Medicine and Infectious Diseases, 24, pp.59-64. doi: 10.1016/j.tmaid.2018.05.008.