Melatonin and Jet Lag: What the Research Looked At

Melatonin is examined in research on circadian rhythms and time-zone travel, and this article reviews evidence and questions for physician guidance.

By UAE Peptide Clinic Research Desk

Dubai and Abu Dhabi sit at the crossroads of some of the busiest long-haul routes in the world, so many UAE residents cross three, five or eight time zones several times a year. Jet lag is the result of the body clock, which runs on an internal schedule of roughly 24 hours, being out of step with the local day and night. Melatonin is the supplement most often discussed for this problem, and it is also one of the most misunderstood. This article explains what melatonin does in the body, what research has looked at, and why when you take it matters as much as whether you take it.

What melatonin actually does

Melatonin is a hormone produced by the pineal gland in the evening as light fades. Its rise tells the body that biological night has begun, which is why it is often called a timing signal rather than a sedative. It contributes to the regulation of the natural sleep-wake cycle, and that is the function that makes it relevant to travel, shift work and irregular routines.

Because melatonin acts as a signal for the body clock, the same dose can nudge the clock earlier or later depending on the time it is taken. Studies of phase shifting suggest that melatonin taken in the late afternoon or early evening tends to move the clock earlier, while melatonin taken in the early morning tends to move it later. Bright light has the opposite pattern, which is why light exposure and melatonin timing are usually considered together.

Melatonin works as a timing signal for the body clock, so the hour it is taken tends to matter more than the amount.

What research has looked at for travel

Reviews of trials in travellers have generally found that melatonin taken near the target bedtime at the destination has been associated with better self-reported sleep after crossing several time zones, with the effect appearing more consistent for eastward travel and for journeys crossing five or more zones. Findings are not uniform, study quality varies, and individual responses differ widely, so research suggests melatonin is one tool among several rather than a dependable fix.

Dose has also been studied. Trials have used a wide range, and lower doses have often performed similarly to higher ones in the research on sleep timing. A higher strength is therefore not automatically a better one, and the right amount for you is a conversation for a clinician who knows your history.

Practical timing principles

The principles below reflect how the research is commonly interpreted. They are educational rather than personal advice.

• Eastward trips, such as London to Dubai: the body clock needs to move earlier, so studies have usually placed melatonin close to the target bedtime at the destination, with morning light exposure supporting the shift.
• Westward trips, such as Dubai to New York: the clock needs to move later, and many travellers adapt without supplements because staying up later is easier than falling asleep early.
• Short trips of one or two days: it is often simpler to stay on home time than to try to shift at all.
• In studies, melatonin was generally taken only when participants could go to bed shortly afterwards, in a dark and quiet room; it should not be followed by driving or operating machinery.
• Sensible basics matter too: daylight at the right hours, regular meals on destination time, hydration, and limited caffeine and alcohol on the flight.

Quality, registration and regulation

Rules for melatonin differ between countries, and in the UAE the way a product is classified and registered matters. Check that any product you buy is supplied through a licensed channel, that the label states the exact amount per capsule, and that the form and dose suit your plan. Imported products carried in a suitcase may not meet local requirements, so it is worth checking before you travel. Supplements are food supplements, not medicines, and they are not intended to diagnose, treat, cure or prevent any condition.

Who should speak to a doctor first

Anyone who is pregnant or breastfeeding, taking medication, or managing a medical condition should speak to a doctor before using melatonin. Interactions have been described with blood thinners, blood pressure medicines, immune-modifying drugs, diabetes medicines and sedatives, among others. Melatonin can cause daytime drowsiness, vivid dreams or headaches in some people. If you have persistent sleep difficulty rather than travel-related disruption, that deserves a proper assessment rather than a supplement.

If you want to understand whether any of this is relevant to you, an independent DHA-licensed physician can review your case. Take the two-minute quiz at /find-my-stack or book a physician consultation at /book (AED 300 deposit, credited to your first order).