Melatonin and the Circadian Rhythm

Melatonin is a natural hormone produced by the brain which regulates your internal body clock (circadian rhythm) and is a popular treatment for jet lag.

Jetlag can be brutal, days or even weeks spent awake at 3 in the morning and fast asleep in the afternoon. Some frequent travellers obsess on specific routines to avoid increasing the likelihood of disturbed sleep, from proactively adjusting to to the new time zone before arriving, to staying awake on a red-eye flight to sleep on arrival. While these techniques can be useful in the right situation, they don’t work in most, and some people are more susceptible to insomnia. 

Across the Atlantic, the number of people in the US using melatonin has doubled, and over 3.1 million Americans use it to improve sleep. While it is available in up to 10mg doses in the US as a dietary supplement, in the UK melatonin is classed as a medicine and is available on prescription in a (2mg) slow release form; and only for those aged over 55 suffering from a short term sleep disorder. Note, melatonin is also available  ‘unlicensed’ in the UK where a doctor deems it approritate for conditions outside of the aforementioned use case; although this is rare.

woman asleep with melatonin

How does it work?

The precursor to melatonin is serotonin, a primary neurotransmitter modulating mood balance, among other functions. Melatonin is produced in the pineal gland, in the middle of the brain, and it helps regulate day and night cycles.

The retina transmits signals related to exposure to light or darkness to reduce or stimulate melatonin production, and consequently, the body naturally secretes melatonin when it’s dark, as a signal to go to sleep. 

What are the benefits?

Melatonin can help you fall asleep, albeit indirectly, studies indicate it can reduce insomnia if taken 90 minutes before bedtime. Although, melatonin doesn’t appear to be as effective as other remedies promoting sleep.

It is commonly used to reset the body clock when travelling long distances across time multiple time zones, as a short term solution for jet lag. Research indicates the realised benefits improve the more time zones crossed, but less so for westward travel. The study concluded melatonin is particularly useful for the treatment of jet-lag, but the pharmacology and toxicology of the substance needs further investigation.


Products sold over the counter (outside the UK) are usually synthetic copies of melatonin, and the drug is a hormone not merely a sleeping pill or standard supplement. 

Melatonin itself does not induce sleep; it informs your body that it’s night time and to prepare for sleep. Hence, why it’s useful for jet lag. It can also interact with other drugs, and while outside the UK it can be obtained without a prescription, extra care has to be taken to avoid conflicts and its use should always be advised by a medical professional.

CBD vs Melatonin

CBD is a natural compound found abundantly in hemp, and its use is increasing as a sleep aid. While research suggests CBD can help reduce insomnia, most of the studies thus far are pre-clinical. For more information on CBD and studies on sleep please check out our post here.

The debate of CBD vs melatonin is becoming more popular on forums and through anecdotal evidence from the public using both and comparing its use.

Enjoy reading our blog? Subscribe to our newsletter below to receive 10% off your next order and blog updates!


* indicates required

Leave a Reply

Your email address will not be published. Required fields are marked *

Disclaimer: Views expressed here do not necessarily reflect those of Nature & Bloom and its staff. This article is not intended to provide medical advice, diagnosis, treatment, cure or prevention for any disease. Nature & Bloom products have not been evaluated by the MHRA.