Melatonin and sleep

Where it is released from?

Melatonin, commonly known as the sleep hormone, is produced in a tiny endocrine gland in the brain called the pineal gland. It is secreted from there into the bloodstream to communicate information to different parts of the body that respond to light in our environment.

What is its main function?

Melatonin’s primary function is to help regulate our sleep-wake cycles; its release is inhibited by light and encouraged by darkness. This is why people generally sleep better when using blackout blinds or eye masks as it blocks out any excess light at bedtime, promoting the production of melatonin. Melatonin is in relationship with our 24 hour internal clock, referred to as our circadian rhythm. Each person’s is unique to them but this daily cycle of sleeping and waking can be determined largely by our melatonin production. These rhythms are just another example of the miraculous cycles that move through us, as we’re going about our day-to-day lives. It communicates when it’s time for us to get up and use our energy, and tells us when it’s time to wind down and eventually sleep. But everybody’s rhythm is different - some are more productive and energetic at night whereas others like to wake up with the sun.  Without melatonin, the circadian rhythms could stop functioning and in turn lead to exhaustion and sleeplessness. We may not know what our optimal cycle is until we become aware of any imbalances.

And as the seasons change, so do our internal communications systems. In addition to melatonins circadian rhythm, its levels adjust with the seasons - production is naturally higher in autumn and winter when the nights are longer, and in the spring and summer, these levels drop.

What are the effects of imbalances in this hormone?

If we’ve been traveling across time zones or up all night working or partying, this can disrupt our circadian rhythms and knock us off our sleep-wake cycle. Sleeplessness and insomnia are often due to a lack in melatonin.  Even holidays in regions like Scandinavia can interrupt melatonin secretion, especially in Summer when the sun only goes down for a few hours at night. For most of us, darkness is essential for a good night’s rest. Melatonin can be prescribed as part of a treatment plan for sleep related issues such as jet lag, insomnia and Seasonal Affective Disorder, a type of depression that’s related to the change in seasons. Alcohol, caffeine, stress and blood sugar imbalances could also lead to melatonin deficiency.

What is its relationship to lifestyle: diet and stress?

There are natural ways to boost your melatonin levels such as eating melatonin-rich foods like cherries. Bananas, oatmeal, and milk contain the amino acid tryptophan which supports the production of melatonin. Dimming the lights in the evenings and avoiding bright screens, smartphones and laptops before bedtime are other ways to ensure maximum melatonin production when we need it. Unsurprisingly, meditation can also be good pre-bedtime activity to help wind-down. As with all our hormones, melatonin has a unique purpose to support us in maintaining balance, mentally and physically. Sleep is one of the most powerful self-healing tools we have - by understanding each of our own unique circadian rhythms, we respect its needs and meet them by making lifestyle choices that support its smooth song and our smooth sleep.

Words by Amy Mabin

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