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New Science on When and How Melatonin is Produced
Melatonin is called the nighttime hormone because most people think it’s only activated after the sun goes down. It’s true that our bodies produce melatonin at night, but new research shows that nighttime melatonin accounts for just 10 percent of the total melatonin our bodies.
It turns out that the other 90 percent of the melatonin we make happens in the daytime and is triggered by exposure to sunlight.
This daytime melatonin is called subcellular melatonin and it provides essential energy for breathing, eating, digesting, detoxing, pumping your heart, exercising and much more!
Read on for the details on subcellular melatonin and how it is different from the melatonin we all know and love
What is Subcellular Melatonin?
Subcellular melatonin is produced by the mitochondria in our cells—or the energy production centers of the body. Inside of every cell are organelles called mitochondria that oversee manufacturing adenosine triphosphate (ATP), which delivers energy to our cells.
The new study found that the penetrating rays of near infrared light (NIR), which make up a whopping 70 percent of the solar photons hitting the body, is the trigger for making cellular melatonin.
Near Infrared light from the sun can penetrate into the body’s tissues more deeply than any other frequencies of the solar electromagnetic spectrum. Research has found that near infrared light reaches about 60 percent of adult human cells and 100 percent of the cells of a fetus—yes, NIR penetrates bone, and even into our brains.
How Daytime and Nighttime Melatonin are Different
Nighttime melatonin, unlike daytime melatonin, helps us sleep so we can maintain our connection to nature’s circadian rhythms.
Like a nighttime janitor, melatonin is also in charge of detoxification and repair of the body and brain. Nighttime melatonin, produced in the pineal gland, is also called circulatory melatonin because it circulates throughout the body via the blood stream.
And while daytime melatonin production is triggered by sun exposure, nighttime melatonin kicks in once the sun goes down. The pineal gland is triggered to secrete circulatory melatonin when your body can no longer access visible violet, blue, and green daylight.
While circulatory melatonin was long considered the hormone in charge of sleep, rejuvenation, and repair, it’s now understood to be more of a supplemental source of melatonin, emerging during dark periods of low solar stimulation and less cellular activity.
The researchers concluded that while circulatory melatonin is the “Hormone of Darkness,” subcellular melatonin is the “Hormone of Daylight.”
See also The Longevity Benefits of Melatonin
Daytime Melatonin is a Powerful Antioxidant
The benefits of melatonin as a powerful antioxidant have been well-known for decades, but only recently have researchers identified melatonin as the major antioxidant, or repair mechanism, associated with cellular energy.
The process of energy production creates waste in the form of reactive oxygen species (ROS). ROS is considered one of the most damaging forms of oxidation in the body, and to mitigate this potential damage, the body produces melatonin, a potent antioxidant.
Inside your mitochondria are extremely important enzymes called cytochrome c oxidase. Cytochrome c oxidase is activated by infrared light and helps the body use oxygen more efficiently in the production of ATP, while also being the key enzyme in transforming the sun’s infrared light into melatonin.
See also 5 Ways the Sun Can Help You Sleep
Melatonin, Aging, and Infrared Light
The constant production of ROS in our cells can lead to inflammation. This process can increase with age, while our ability to mitigate it declines with age.
Much of this age-related damage is due to a deficiency of sunlight, or, more specifically, a deficiency of infrared light and the production of daytime melatonin.
The best time to get infrared light exposure is during the sunrise and sunset, when there is unopposed infrared and red light without damaging ultraviolet (UV) light.
At sunrise and sunset, when the sun is low in the sky, higher frequencies of UV light are blocked by the atmosphere, while the lower frequencies of visible red and invisible infrared light easily penetrate the atmosphere and the body.
One rule of thumb is that if your shadow at sunrise and sunset is longer that your body length, there is minimal UV radiation, and it’s safe to sunbath.
Infrared light is powerfully scattered by the plant kingdom. Green leaves not only absorb infrared light, but they disperse it in every direction. So even while sitting under a shade tree, you are absorbing a healthy dose of infrared light. At the same time, the leaves are blocking the damaging UV rays, making a shade tree the perfect sunscreen.
In fact, the health benefits of being in nature may be in large part due to exposure to reflected infrared light.
In Ari Whitten’s book, Red Light Therapy, he writes about how red and near infrared light therapy can better support energy, combat aging, skin health, fat loss, improve muscle recovery, improve mood and cognitive function, speed up healing from injury, and improve hormonal and metabolic health.
Most Americans spend 90 percent of their waking hours under artificial light that is devoid of red and infrared lighting.
Living under LED and fluorescent lighting has created a deficiency of red and near infrared light.
Among other factors, the lack of red and infrared light exposure is linked to a significant lack of subcellular melatonin.
As a result of billions of years of evolution, we are admirably adapted to the sun’s radiation. In nature, the human body would never be exposed to damaging UV light without ample exposure to red and near infrared light that provides the protection form UV light we so desperately lack. The unopposed infrared light and sunrise and sunset prepares and repairs the skin from the midday UV light exposure.
The takeaway here is to be in nature as much as possible and do your best to bath in infrared light at sunrise and sunset. You can also soak up a bright sunny day under a shade tree without the need for sunscreen everywhere. Wear protective clothing on the areas you want to protect—the infrared still will work its magic through clothing!