Melatonin: The Hormone That Sets Your Internal Clock

Melatonin is often called the sleep hormone, but it does much more than help you drift off at night. It is a powerful regulator of the circadian rhythm, the 24 hour internal clock that guides sleep, mood, digestion, and even hormone production. When melatonin release becomes disrupted, the entire system can fall out of sync.

Where Melatonin Comes From

Melatonin is produced by the pineal gland deep inside the brain. Production increases naturally as daylight fades. Light signals from the eyes travel to the suprachiasmatic nucleus which tells the pineal gland when to raise or lower melatonin levels.

(Source: Arendt, The New England Journal of Medicine, 2000.)

During the day melatonin stays low. As evening approaches the brain begins releasing more which signals the body that it is time to shift into rest mode.

What Melatonin Actually Does

Melatonin does not force the body to sleep. Instead it prepares the brain and body for sleep by changing internal conditions by:

1. Lowering Body Temperature

A small drop in core temperature helps initiate the sleep cycle.

2. Calming the Nervous System

Melatonin supports the parasympathetic system which promotes relaxation and helps reduce nighttime anxiety.

3. Regulating the Circadian Rhythm

It acts like a biological time cue that synchronizes internal processes.

(Source: Pandi Perumal et al., Physiology and Behavior, 2007.)

4. Supports Antioxidant and Immune Functions

Research shows that melatonin protects cells from oxidative stress and supports immune balance.

(Source: Hardeland, Molecules, 2018.)

Why Melatonin Gets Out of Balance

Modern life easily disrupts melatonin. Some of the most common disruptors include:

Artificial Light Exposure

Blue light from screens delays melatonin release and tricks the brain into thinking it is still daytime.

Irregular Sleep Patterns

Shift work, late nights, or inconsistent sleep schedules confuse the internal clock and weaken melatonin signaling.

Stress

High stress increases cortisol which can interfere with melatonin production.

Aging

Melatonin naturally decreases with age which can make sleep less consistent.

Melatonin Supplements: Helpful or Not

Melatonin supplements can help in some cases, especially for jet lag, delayed sleep phase disorder, or temporary schedule disruptions. They are not a strong sedative but they can shift the internal clock when used properly.

(Source: Sack et al., Sleep, 2007.)

However long term use is less studied and taking too much can lead to grogginess or vivid dreams. For most people the goal is to fix the rhythm, not rely on a pill.

Natural Ways to Improve Melatonin Production

Get Morning Sunlight

Bright natural light in the morning strengthens circadian rhythm and makes nighttime melatonin release more predictable.

Limit Screens at Night

Even one hour of reduced screen exposure can improve melatonin timing.

Create Consistent Sleep Times

When bedtime and wake time are stable, melatonin production becomes stronger and more reliable.

Use Dim, Warm Lighting in the Evening

This mimics sunset which tells the brain to start releasing melatonin.

Eat Earlier

Late night eating may delay the circadian system and suppress melatonin.

Final Thoughts

Melatonin is not just a sleep aid. It is a master hormone that keeps the entire internal clock running smoothly. When melatonin is balanced, sleep becomes easier, mood becomes more stable, and the body has an easier time healing and regulating itself. Simple lifestyle habits can make a huge difference in restoring natural melatonin rhythms.