Did you know melatonin is a hormone? +6 Shocking Facts...

Have you used melatonin to help with trouble falling asleep? If you have, you’re not alone. According to the National Institute of Health, melatonin use in the U.S. has more than 5x’d since 1999. 1  And yet, even with more people than ever using melatonin to sleep faster, longer, and more deeply — the research suggests melatonin isn’t the “sleep cure-all” many believe it to be. Nor is it as harmless as you may think…

To help you navigate the research and current state of melatonin, we’ve put together a quick but comprehensive guide to all things melatonin, 6 key facts you ought to know, and 4 effective sleep hygiene strategies from UC Berkeley Professor and Author of the New York Times Bestseller, “Why We Sleep,” Dr. Matt Walker.

Table of Contents:

- What is melatonin?

- What triggers melatonin production?

- 6 Melatonin facts that will surprise you…

      - #1 Melatonin isn’t a magical sleep cure 

      - #2 Is melatonin safe?

      - #3 Less is more with melatonin dosages

      - #4 Supplements could have -83% less to +478% more melatonin than labeled

      - #5 Your melatonin could have surprise ingredients

      - #6 1 in 5 kids currently use melatonin

- 4 Dr. Matt Walker-approved tips for better sleep

 

What is melatonin?

Melatonin is a hormone naturally produced by the pineal gland (a small gland located in the center of the brain that regulates your sleep-wake cycle.) It plays a critical role in our sleep-wake cycle, making us feel drowsy and helping us fall asleep at night. In most healthy adults, the body typically produces about 0.1 mg a night. 

But what does melatonin actually do? According to Dr. Matthew Walker, “Melatonin helps schedule the timing of your sleep, but melatonin does not significantly change the quantity or the quality of your sleep.” 

Another way of thinking about it is with the analogy of an Olympic race. Melatonin acts as the gunshot that triggers the start of the race, rather than actively participating in the race itself.

What triggers melatonin production?

The key factor that prompts the pineal gland to release melatonin is light. Essentially: Darkness promotes melatonin production, while bright light limits it.

Melatonin levels typically reach their peak after about 2 hours of stimulation. So experts suggest dimming the lights about 2 hours before bedtime to time the effects of melatonin properly for your sleep schedule.

6 Melatonin facts that will surprise you…

Melatonin supplement - Melatonin © Irinayeryomina | Dreamstime.com

#1 The research says: Melatonin isn’t a magical sleep cure 

Does falling asleep 4 minutes faster seem impressive to you? Because, on average, that’s what melatonin offers. A meta-analysis of 13 studies found that while melatonin did benefit sleep, it only reduced the time to fall asleep by 4 to 7.5 minutes. The study also found it only increased the total time spent sleeping vs. awake in bed by 2.2% and total time asleep by ≈ 12 minutes. 2

That being said, research has shown that it can benefit some sleep problems, like circadian rhythm disorders. This is because while melatonin doesn’t directly improve sleep, it helps set in motion the physiological prerequisites to help time your sleep properly.

Conditions and contexts where melatonin may offer more benefits include: 

3


  • Alzheimer’s disorder
  • Jet lag and adjusting to time zones
  • Delayed sleep phase disorder (DSPS)
  • Advanced sleep phase disorder (ASPS)
  • Children with neurogenic neurodevelopmental disorders
  • Children with autism spectrum disorder and sleep disturbances
  • Patients 55 years and older with hypertension and sleep issues
  • Blind populations (aligns sleep schedule in the absence of environmental cues)

  • #2 Is melatonin safe?

    Many think of melatonin like a vitamin. After all, it’s in the same place in the grocery store aisles. But the truth is that even short term, researchers have found that melatonin can have a number of mild side effects. 4

    Common mild side effects of melatonin: 4

    • Headaches
    • Dizziness
    • Stomach cramps
    • Nausea
    • Daytime sleepiness
    • Mood changes (e.g., short bouts of irritability and depression)
    • Vivid nightmares and/or dreams

    The Sleep Foundation notes that adverse side effects are more likely to occur with doses above the recommended 1-3 mg. 4

    A side effect you may not have to worry about is dependence. For example, one study found that neither a 0.5 mg dose of melatonin given to shift workers every night for 7 days nor a 50 mg melatonin dose taken daily over 37 days led to any impairment of natural melatonin production. 5

    Is it safe to take melatonin every night?

    When it comes to the safety of melatonin, most studies have focused on short-term melatonin use. For this reason, researchers caution against using melatonin long-term ( > 3-4 weeks), and federal guidelines advise only using melatonin as a short-term sleep aid.

    A recent survey by the Sleep Foundation found that U.S. adults who use melatonin take it an average of 211 days each year. This level of sustained melatonin use and its long-term effects haven’t been studied, and cannot be guaranteed safe. 6

    #3 Less is more with melatonin dosages

    You might think, “More melatonin means more sleepiness, right?” But according to the research, this doesn’t appear to be true. The body naturally only produces about 0.1 mg of melatonin each night to promote sleep. While the best dosage varies by age, gender, genetics, and health conditions — experts typically suggest the best amount of melatonin to take for sleep support is between 1-3 mg, and no more than 5 mg. 6

    #4 Supplements could have -83% to +478% more melatonin than labeled

    Melatonin is legally considered a dietary supplement, so it isn’t regulated by the U.S. Food and Drug Administration (FDA). That means there can be a lot of variability in the quality of melatonin from brand to brand and bottle to bottle. 

    Additionally, a review of 31 commercial melatonin supplements found that actual melatonin content ranged from as much as -83% less to +478% more melatonin than was on the label!

    Researchers also found that for over 71% of melatonin supplements, melatonin content wasn’t within a 10% margin of labeled levels. 7

    #5 Your melatonin could have surprise ingredients

    The same study found that 26% of melatonin supplements also contained unlabeled serotonin. This is critical, as the National Center for Complementary and Integrative Health reports that serotonin is “a hormone that can have harmful effects even at relatively low levels.” 7, 8

    Melatonin supplements are sometimes combined with CBD. However, the FDA writes that it is “currently illegal to market CBD by adding it to a food or labeling it as a dietary supplement,” which allows it to bypass FDA oversight. Additionally, researchers have found that CBD levels in melatonin supplements can be between 4% and 18% higher than what’s on the label. 9

    #6 1 in 5 kids currently use melatonin

    long-term melatonin use has not been tested for children and could impair healthy development! Photo credit: ID 133509696 | Melatonin © Irinayeryomina | Dreamstime.com

    One study found that as many as 20% of children who use melatonin take it every night. 10 But is melatonin safe for kids?

    Researchers and experts in child development find the unregulated and growing use of melatonin with children troubling for a few reasons: 9, 10
    1. Aside from children with autism spectrum disorder or neurogenic neurodevelopmental disorders, melatonin hasn’t shown significant benefits for children.

    2. Long-term melatonin use by children has not been studied extensively, meaning there could be significant impacts on children as they grow. Remember - melatonin is a hormone and could have widespread effects on your child’s healthy development!

    3. Many melatonin supplements contain unlisted ingredients or mislabeled amounts of ingredients like serotonin and CBD, which can be dangerous for children.

      (One study even found that one of the melatonin gummy supplements they tested had no melatonin at all — It was made entirely of CBD.)

    4. A report published in March 2024 by the US Centers for Disease Control and Prevention found that about 11,000 children were seen and treated in emergency rooms after consuming melatonin while unsupervised between 2019 and 2022. 

    For this reason, more experts have advised exhausting all other options before recommending melatonin as a last resort for severe sleep disorders present with certain neurodevelopmental conditions.

    4 Dr. Matt Walker-approved tips for better sleep

    1. Naturally boost melatonin with diet

    Foods like turkey, eggs, milk, pumpkin seeds, almonds, walnuts, and more are rich in an essential amino acid called tryptophan. When digested, tryptophan is converted to serotonin, which is a precursor to melatonin and can support your body’s natural melatonin levels.

    2. Get sunlight during the day

    Sunlight also helps boost your body’s natural production of serotonin, which later converts to melatonin at night. The daylight exposure also helps inform your brain’s sleep-wake cycle, helping keep your energy levels aligned with your daily schedule.

    3. Create a consistent nighttime routine

    According to Matt, going to sleep is less like flipping a light switch and more like landing a plane. “It takes time for your biology to start to wind down and… descend you down onto the terra firma of good sleep at night,” says Matt. 

    To help, Matt suggests creating a routine that tells your brain it’s time to begin winding down for sleep. Try heading to bed at the same time every night and incorporating calming activities like reading, breathing techniques, and meditation. Or, let Somnee do the heavy lifting and help you easily unwind for a night of deep, restful sleep.

    4. Be mindful of light at night 

    Light can be your best friend or your worst enemy when it comes to melatonin and sleep. Use it to your advantage by dimming the lights about 2 hours before you’d like to fall asleep. Also, try to limit electronic use. If you do need to use your computer or phone, adjust your screen settings to filter out blue and green lights and prioritize more red and orange lights.


    Want more tips for better nightly rest?

    Check out our blog: 10 Tips for Better Sleep, from Dr. Matt Walker

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