Melatonin and Sleep


Melatonin and Sleep

What is Melatonin?

Believe it or not, we would all function perfectly if clocks didn’t exist. Our bodies are regulated with their own internal clock, by the rising and setting of the sun each day.

There’s a part of our brain called the hypothalamus: it controls hunger, thirst, body temperature and sleep. When the sun comes up, the hypothalamus “sees the light” and stimulates cortisol and other hormones which cause you to wake up. That’s why sunlight wakes us up. It’s not the light itself, it’s the reaction of the brain when it senses light: it produces hormones that wake us up.

Melatonin is the flip side of this.

When the hypothalamus senses darkness at sunset each day, it triggers the release of melatonin: a hormone that brings about sleep and regulates sleep patterns. This helps us wind down and prepare for sleep.

Melatonin is produced when the sun starts to set and the light decreases – the brain responds to darkness by releasing melatonin.

Overnight, the brain continues to release melatonin to help us continue sleeping, until it slows down and stops around 5am in preparation for a new day.

Because melatonin is only secreted when it’s dark, it’s often referred to as the “darkness hormone.”

melatonin in a bottle


The Relationship between Melatonin and Sleep

In a healthy person under the right conditions, melatonin works to create drowsiness before bed and help bring about sleep onset. Here’s how it works:

About two hours before bedtime, your brain starts to secrete small amounts of melatonin, which helps you get more tired as bedtime approaches. This helps you feel tired enough to fall asleep.

Because melatonin is so sensitive to light, it’s release can be disrupted by screens and fluorescent lights. Scrolling on your phone an hour before bed tells your brain that’s it’s 2pm, not 9pm, and there’s no need for melatonin right now.

Melatonin deficiency can cause restlessness, insomnia and waking early in the mornings.


How Do Babies Produce Melatonin?

While in your womb, your baby absorbed your melatonin after it passed through the placenta. After birth, babies start to produce their own melatonin – but in teeny tiny amounts, which is part of the reason that newborns have such erratic sleep patterns. Breastfeeding newborns get melatonin from evening breastmilk which can help with sleep.

Babies start to produce melatonin in more significant amounts at around 12 weeks, which allows their sleep cycles to start regulating more, as they complete the newborn stage. (This is partly why babies start to sleep better as they get older).


Risks of Supplemental Melatonin

Melatonin can be produced synthetically, which is what you’ve seen on Amazon or seen your sister-in-law give her kids. Melatonin supplements are extremely popular for adults, especially as the sleeplessness epidemic we face continues to worsen.

Points to ponder:


  • The FDA doesn’t regulate supplements- and melatonin is a supplement. The FDA (which doesn’t always have our best interests at heart even when it comes to regulated drugs) doesn’t even glance at the bottle of melatonin from production to your nightstand. The quality and amount of melatonin in each bottle may vary from batch to batch, even from the same company. You’re on your own with this one.
  • There have been no safety studies done to understand the effects of melatonin for long-term use. There is evidence to support that supplemental melatonin affects fertility in rodents, even in small doses. There is a possibility that synthetically produced melatonin can have the same effects on humans. We don’t know enough to suggest otherwise.
  • Melatonin can be helpful for neurodivergent children who don’t create enough melatonin, such as children with ADHD or autism. When melatonin is given to children, it should be under the guidance of a pediatrician, with forethought and caution.
  • Melatonin – especially when it comes to children- needs further research. There are no definitive answers about long-term implications, effectiveness and safe dosages. Because we don’t have long-term data, giving melatonin to a child as a long-term solution is a risk.
  • In the United States, you can purchase melatonin as on over-the-counter supplement or even order it on Amazon. But in many other countries, including Japan, Australia, the UK and other European countries, it is available by prescription only. This should give us pause before offering it to our children.

For babies: melatonin should not be given to babies, or to any children under three years of age. This is based on the lack of data on long-term effects, combined with the fact that there are so many ways to help babies sleep without pumping them with synthetic hormones.

For older children: while supplemental melatonin may be ok for short-term use (with neurotypical children) or to help with long-term struggles in neurodivergent children, melatonin should only be given under the auspices and guidance of a pediatrician and should never be given to babies.


Natural ways to Encourage Melatonin Production

If you’ve read this far, you’re probably wondering how you can help your baby get the effects of melatonin without giving her a synthetic hormone that has a great lack of research.

I’ve got you- let’s encourage your baby’s body to naturally produce more melatonin! There are a few simple things you can do to help your baby’s brain naturally secrete more melatonin and regulate her sleep.


  • Make sure your baby is older than 12 weeks. Before that, melatonin is essentially a non-starter.
  • Put your baby to sleep in a very dark room. Blackout curtains are a good start, but they only help if they work! Make sure there’s no light seeping around the edges of the curtains by adhering them to the window frame. This applies for nights and naps.
  • If your toddler is afraid of the dark, use a nightlight with red light, which interferes least with melatonin production. More on nightlights here.
  • Avoid all screens 2 hours before sleep. Screens emit blue light, which suppresses melatonin production.
  • Expose your baby to sunlight in the morning and in between naps and bedtime. This has a huge impact on your baby’s circadian rhythm and sleep-wake cycles.
  • Keep a consistent bedtime routine. This is a powerful way to signal to your baby’s body that it’s time to start winding down for sleep, which has physical results.

Many times, what we think needs melatonin can be solved with some new skills. For newborns, this can look like sleep shaping, or for older babies, learning how to sleep through the night. I’ve got help for you if you need it – be sure to check out my baby sleep courses here.


Will starting solids help your baby sleep for a longer stretch at night?

You might have heard parents swear “as soon as we started solids she started sleeping 8 hours!” causing you to wonder if you should be feeding your baby real food too. What wouldn’t we do to gain a few more minutes of sleep at night?

Sadly, it doesn’t help. There is very little evidence that suggests a positive correlation between solids and longer stretches of sleep, and there is some evidence that suggests starting solids too early can disrupt sleep (just when you thought things couldn’t get any worse!)


3 secrets to get your baby
sleeping through the night!