The Melatonin Story Almost Everyone Gets Wrong

Most people think of melatonin as the hormone your pineal gland releases at night to help you fall asleep. While that is true, it is only a small part of the story. The vast majority of the melatonin your body produces is actually made inside your cells, where it protects your mitochondria throughout the day. Understanding what stimulates this process completely changes the way we think about sunlight, nature, and human health. 

The Melatonin Story Most People Never Hear

Ask someone what melatonin does, and chances are they will tell you it helps you sleep.

They are not wrong.

As daylight fades, your pineal gland begins producing melatonin, signaling to the rest of your body that nighttime has arrived. That hormone helps coordinate your circadian rhythm, prepares your brain for sleep, and synchronizes countless physiological processes with the light-dark cycle.

Because of this, melatonin has earned the reputation of being "the sleep hormone." It is the reason so many people reach for a melatonin supplement after a restless night or while traveling across time zones.

But that is only one piece of a much bigger story.

What most people do not realize is that the pineal gland accounts for only a small fraction of the melatonin your body produces each day. Approximately 95% of your daily melatonin production occurs outside the pineal gland, inside tissues throughout the body, particularly within your mitochondria.

Researchers often refer to this as subcellular, extrapineal, or mitochondrial melatonin.

Unlike pineal melatonin, its job is not to make you sleepy.

Its job is to keep your cells alive.

Once you understand that distinction, the conversation around melatonin shifts dramatically. Instead of thinking about it as something your body produces only after sunset, you begin to realize that your cells are relying on it throughout the entire day.

Why Your Mitochondria Make Their Own Melatonin

Every second of every day, your mitochondria are producing energy through the electron transport chain. This remarkable system transfers electrons from one protein complex to the next, creating the energy your cells need to perform virtually every function required for life.

It is an extraordinarily elegant process, but like every biological system, it is not perfectly efficient.

As electrons move through the electron transport chain, some inevitably escape before reaching their intended destination. Those escaped electrons generate reactive oxygen species.

This is where a lot of confusion exists.

Reactive oxygen species are often portrayed as something entirely harmful, but that is not actually the case. Your body intentionally produces them because they serve important signaling functions. They become problematic only when they accumulate faster than your body can manage them.

When that happens, oxidative stress begins damaging proteins, lipids, DNA, and eventually the mitochondria themselves. Over time, that damage can interfere with healthy cellular function and contribute to the loss of efficient energy production.

Your mitochondria cannot afford to wait until bedtime for protection.

They need it every minute of the day.

That is exactly why they produce their own melatonin.

Rather than relying on the pineal gland to send melatonin through the bloodstream hours later, each mitochondrion creates melatonin right where oxidative stress is occurring. Acting as a powerful free radical scavenger, mitochondrial melatonin helps neutralize excess reactive oxygen species generated through normal metabolism while also helping protect the cell from additional oxidative stress caused by modern environmental stressors, including non-native electromagnetic fields.

I often compare this to cleaning your home.

Imagine allowing every dirty dish, every load of laundry, and every mess to accumulate all day long before cleaning anything. By evening, the task would feel overwhelming. Most of us naturally clean as we go because it keeps the house functioning and prevents small messes from becoming major problems.

Your mitochondria operate in much the same way.

Instead of allowing oxidative stress to build throughout the day, they continually produce melatonin exactly where it is needed, cleaning up excess free radicals as they are generated. This allows the electron transport chain to continue functioning efficiently while limiting unnecessary cellular damage.

One detail that I find especially fascinating is that the electron transport chain is not only producing ATP. During this process, your mitochondria are also creating metabolic water. In other words, two of the body's most important protective resources, metabolic water and mitochondrial melatonin, are produced together as healthy mitochondrial function unfolds.

That naturally raises another question.

If most melatonin is produced inside the mitochondria, what tells the mitochondria to make it?

The Missing Signal

One of the most fascinating answers is near-infrared light.

When people think about sunlight, they usually think about vitamin D, ultraviolet light, or perhaps the warmth they feel on their skin. Those are certainly important, but they are only part of what sunlight provides.

Near-infrared light makes up roughly 40% of natural sunlight, yet it receives very little attention.

Research suggests that during the fourth step of the electron transport chain, near-infrared radiation helps stimulate the production of both mitochondrial melatonin and metabolic water. In other words, one of the most abundant wavelengths in nature directly supports one of the body's most important protective systems.

To me, this is another beautiful reminder that our biology was designed outdoors.

We did not evolve under LED lights or inside climate-controlled buildings. For hundreds of thousands of years, our mitochondria developed in an environment where they were continuously exposed to the complete spectrum of natural sunlight from sunrise until sunset.

Our cells still expect those signals today.

Unlike ultraviolet light, which is only present during certain times of the day depending on your location and the season, near-infrared light is present throughout nearly the entire daylight period. From the first light of dawn until the sun disappears below the horizon, these wavelengths are constantly reaching your skin, providing your mitochondria with an environmental signal they have relied upon throughout human history.

But here is the part I found most remarkable...

The Amazing Thing About Trees 

But here is the part that fascinated me most.

One of the most groundbreaking papers I have read on this topic, by Zimmerman and Reiter, pointed out something that most of us have never considered. Trees, leaves, and other green vegetation reflect enormous amounts of near-infrared light.

Think about what that means.

Most people assume they have to stand in direct sunlight all day to receive the benefits of natural light. While direct sun certainly has its place, near-infrared light behaves differently than ultraviolet light. It is abundant throughout the day, and nature itself reflects it back toward us.

In other words, simply sitting beneath a tree, walking through a forest, relaxing in a park, or spending time in your garden still surrounds you with biologically meaningful amounts of near-infrared light.

To me, this is one more explanation for something many of us have experienced without understanding why.

People consistently report feeling calmer, clearer, and more energized after spending time in nature.

Perhaps that feeling is not simply psychological.

Perhaps your cells are receiving environmental signals they have depended on throughout human history.

This is one of the reasons I encourage people not to think of nature as simply "being outside." Nature is an environment rich with biological information. Every moment spent outdoors exposes you to countless signals your body was designed to receive, including the near-infrared wavelengths that help support healthy mitochondrial function.

Why Modern Life Is Missing This Signal

Unfortunately, the modern world has dramatically changed our relationship with light.

Today, many people spend well over 90% of their lives indoors. We leave our homes before sunrise, commute inside vehicles, spend the day in offices or classrooms, return home in the evening, and often finish the day in front of another screen.

Even when sunlight streams through a window, it is not the same light our ancestors experienced.

Modern window glass blocks much of the near-infrared spectrum, and many newer buildings intentionally use infrared-blocking coatings to improve energy efficiency. At the same time, incandescent light bulbs, which naturally emitted significant amounts of infrared light, have largely disappeared from our homes and workplaces. They have been replaced by LED lighting that contains very little near-infrared radiation.

Our indoor environments may appear bright to our eyes, but from the perspective of our mitochondria, they are missing a substantial portion of the light spectrum our biology evolved with.

Our cells are not simply responding to brightness.

They are responding to the complete spectrum of natural light.

When those wavelengths are absent day after day, we remove one more environmental signal that helps support healthy mitochondrial function.

Can Red Light Therapy Replace Nature?

People often ask whether red light therapy panels can provide the same benefits.

They certainly have value.

Many high-quality panels emit one or two wavelengths of near-infrared light that have been studied for supporting mitochondrial function, tissue repair, and recovery. (Find my most trusted brands here.) They can be an excellent tool, particularly for people who spend much of their time indoors or who are unable to get outside consistently.

But they are still only a small piece of what nature provides.

Sunlight is not static. From sunrise until sunset, the intensity changes, the angle changes, and the blend of wavelengths changes minute by minute. Your body receives visible light, near-infrared light, ultraviolet light at the appropriate times of day, changing temperatures, natural magnetic fields, fresh air, and countless other environmental signals that all work together to regulate your biology.

No panel can reproduce that complexity.

Technology can be incredibly helpful.

Nature remains the original design.

The Other 95% Of The Melatonin Story

One of the biggest takeaways from this research is that the melatonin story begins long before bedtime.

Most conversations about melatonin focus on what happens after the sun goes down. We talk about darkness, blue-light blockers, sleep hygiene, and melatonin supplements. While those conversations have their place, they often overlook the fact that your mitochondria have been relying on melatonin all day long.

Every moment your cells are producing energy, they are also producing reactive oxygen species. Every moment they are producing metabolic water, they are also relying on subcellular melatonin to help protect themselves from oxidative damage. That process is not driven by darkness. It is supported by the natural environmental signals your body evolved to receive throughout the day.

To me, this completely changes the way we think about health.

Supporting healthy melatonin production is not simply about what you do before bed. It is about how you spend your entire day.

Spend time outside whenever you can. Eat lunch outdoors. Take a walk beneath the trees. Work in your garden. Sit in a park. Allow your skin to be exposed to natural sunlight when appropriate, and do not underestimate the value of simply being surrounded by living green spaces.

These habits do far more than improve your mood.

They help reconnect your mitochondria with an environment that has shaped human biology for hundreds of thousands of years.

The next time you hear someone describe melatonin as "the sleep hormone," remember that they are only telling a small part of the story.

The other 95% is happening quietly inside your cells every day, helping your mitochondria produce energy, manage oxidative stress, and protect themselves from damage. And one of the simplest ways to support that remarkable process is also one of the oldest.

Step outside.

Related Research & Reading

• Melatonin as a Mitochondria-Targeted Antioxidant: One of Evolution's Best Ideas
  Cellular and Molecular Life Sciences | 2017 
• Biological Effects and Medical Applications of Infrared Radiation
  Journal of Photochemistry and Photobiology B: Biology | 2017
• Primary and Secondary Mechanisms of Action of Visible to Near-IR Radiation on Cells
  Journal of Photochemistry and Photobiology B: Biology | 1999
• Mitochondria and Light: An Overview of the Pathways Triggered in Skin and Retina with Incident Infrared Radiation
  Journal of Photochemistry and Photobiology B: Biology | 2023
• The Body Electric
  Robert O. Becker, M.D. | 1985

FAQs

What is the difference between pineal melatonin and mitochondrial melatonin? 
Pineal melatonin is produced in the brain primarily after dark to help regulate your sleep-wake cycle. Mitochondrial melatonin is produced locally inside cells throughout the day, where it helps protect mitochondria from oxidative stress and supports healthy cellular function.

Does artificial light interfere with mitochondrial melatonin?
Artificial light cannot fully replace the complete spectrum of natural sunlight. Modern indoor environments are especially lacking in near-infrared light, a wavelength believed to support mitochondrial melatonin production, while excessive artificial light at night can also disrupt normal circadian signaling.

What is photobiomodulation?
Photobiomodulation, commonly referred to as red-light therapy, is the use of specific wavelengths of red and near-infrared light to influence cellular function. It is commonly studied for its effects on mitochondrial activity, tissue repair, recovery, inflammation, and cellular energy production.

Can spending time in nature support mitochondrial health even on cloudy days?
Yes. Near-infrared light remains present even when the sun is behind clouds, and trees and other vegetation reflect significant amounts of it. Spending time outdoors still provides your body with many of the natural environmental signals it evolved to receive.

Why is mitochondrial health so important for overall health?
Mitochondria produce the energy that powers nearly every process in the body. When they function well, cells can repair, communicate, and perform their normal jobs more efficiently. Because every organ depends on healthy mitochondria, supporting mitochondrial function is foundational to overall health.