Our bodies run on a 24-hour internal clock that regulates numerous circadian rhythms, including the sleep-wake cycle. Melatonin, a hormone that sends a message to our brain that the day is done and it’s time for sleep, is a key hormone in this sleep-wake cycle.

You are probably familiar with melatonin. It’s become a very popular supplement and search term in recent years because most U.S. adults are sleep deprived; only 48% of men and 36% of women are getting the sleep they need according to a December 2023 Gallup poll.1

But melatonin is more than just a simple sleep aid. If you are looking for better sleep, then it’s important to understand what melatonin is, how it cycles in our bodies, and what causes melatonin disruption. Let’s start with the basics. 

What is melatonin?

The “sleep hormone,” the “hormone of darkness,” and even the “Dracula of hormones” – melatonin goes by many names. It earned these nicknames because the body naturally produces melatonin in response to darkness, and because melatonin helps start the sleep process. Beyond sleep, an adequate melatonin level has been reported to be a positive factor in cardiovascular, immune, GI, and bone health.*

Melatonin production starts in the brain’s pineal gland. During the day, the pineal gland is inactive. When the sun goes down and darkness begins, the pineal gland revs up and begins to produce melatonin. When released from the pineal gland, this hormone attaches to special receptors in the brain, as well as in cells throughout the body. From there, melatonin helps the body relax and get ready for a night of restful sleep. Typically, your melatonin level peaks around bedtime, stays elevated throughout the night, and then falls back to daytime levels in the morning. 

Another primary hormone related to your circadian rhythm is cortisol. It acts something like the mirror image opposite of melatonin. Made in the body’s adrenal gland, cortisol rises in the morning and signals your body that it’s time to get out of bed and start the day. When it’s time for bed, your cortisol level starts to dip, and it is melatonin’s turn again. 

That is how it’s ideally supposed to work. But, as many Americans know, the sleep-wake cycle can become disrupted.

Disrupting melatonin levels 

Although melatonin production varies from person to person, the average individual produces enough melatonin naturally to properly promote sleep. But in some cases, melatonin production can become disrupted. A primary culprit? Simply getting older – aging is a significant factor in diminishing melatonin levels.2

Another factor for melatonin disruption is the “digital age.” Artificial light, primarily blue light from television, cell phones, and computer screens, can put our melatonin schedule on pause. According to studies, blue light tricks your body into thinking it is still daytime.3 And that means your pineal gland will not release the signal that it’s time for sleep. 

Other factors that contribute to melatonin disruption include: 

Can supplements help? 

With the rise of sleep deprivation in the United States, it is no wonder melatonin supplements have surged in popularity. And for good reason – supplementing with melatonin an hour before bedtime can help you fall asleep quicker and stay asleep longer.* 

In individuals who have difficulty sleeping or who have an altered circadian rhythm because of jet lag or night shift work, melatonin supplementation promotes the resynchronization of this cycle.* Supplementation also benefits those whose difficulty sleeping is caused by an aging-related decrease in the body's ability to synthesize melatonin from the amino acid tryptophan.

Of course, supplements are only part of the solution. It is also important to implement lifestyle measures that promote optimal sleep – think of it as your daily bedtime routine. Creating the right conditions can be your ticket to dreamland. Steps for an optimal sleep environment include: 

  • Eliminating light in the bedroom
  • Avoiding blue screens one hour before bedtime
  • Exercising daily (but not right before sleep) 
  • Eating dinner at least 2-3 hours before bed
  • Committing to a relaxing pre-sleep ritual, such as reading, listening to soothing sounds, or practicing meditation
  • Adjusting the bedroom temperature to create a comfortable condition

The takeaway 

Get all the benefits of restful sleep with Thorne’s Melaton-3, the formula designed to help balance circadian rhythms.* For a higher dose, consider Thorne’s Melaton-5. Although, even an amount as low amount as 0.3 mg has been shown to support restful sleep.* 

Finally, to fully understand your body’s sleep cycle, you should test to see how your melatonin levels fluctuate. Thorne’s Sleep Test can be taken in the comfort of your home. Our test tracks melatonin and cortisol levels at four different times during a 24-hour period to show you how they fluctuate and give you a better understanding of your sleep cycle. The test results also include personalized recommendations and lifestyle advice for getting your sleep schedule back on track. 

References

  1. Fioroni S, Foy D. Americans sleeping less, more stressed. Gallup.com. April 15, 2024. https://news.gallup.com/poll/642704/americans-sleeping-less-stressed.aspx. [Accessed January 9, 2025.]
  2. Melatonin. Mayo Foundation for Medical Education and Research. https://www.mayoclinic.org/drugs-supplements-melatonin/art-20363071. [Accessed Feb. 6, 2025]
  3. Gooley J, Chamberlain K, Smith K, et al. Exposure to room light before bedtime suppresses melatonin onset and shortens melatonin duration in humans. J Clin Endocrinol Metab 2011;96(3):E463-E472. 
  4. Stutz J, Eiholzer R, Spengler CM. Effects of evening exercise on sleep in healthy participants: a systematic review and meta-analysis. Sports Med 2019;49(2):269-287. doi:10.1007/s40279-018-1015-0
  5. Durlach J, Pagès N, Bac P, et al. Biorhythms and possible central regulation of magnesium status, phototherapy, darkness therapy and chronopathological forms of magnesium depletion. Magnes Res 2002;15(1-2):49-66. 
  6. Peuhkuri K, Sihvola N, Korpela R. Dietary factors and fluctuating levels of melatonin. Food Nutr Res 2012;56:10.