When you look at the pineal gland, sitting at the base of the brain, one cannot help but think that this pearl-sized gland has a special role to play. Rene Descartes called it “the principle seat of the soul.”
For years, researchers thought the pineal gland was an evolutionary remnant with no real purpose. In the 1970s, they discovered it was the single manufacturer of a special hormone, called melatonin.
Pigeon-holed as “the sleep hormone,” melatonin has become a famous O.T.C. supplement for jet-lag and sleep, in an attempt to help the more than 60 million Americans with insomnia. Yes, melatonin is the sleep hormone—but new research has just begun to understand the powerful role this three-billion-year-old molecule has on our health and longevity.
The pineal gland regulates the dark phase of our light/dark cycles through the secretion of melatonin. In the body, melatonin begins to rise at sunset and peaks in the early morning hours in the dark of the night. Upon sunrise, the blue light from the sun blocks our production of melatonin, and within 30 minutes after getting up, the adrenal stress hormone, cortisol, begins to rise.
Cortisol gives us the energy during the day to get our work done and then starts to fall in the late afternoon. As cortisol falls, shortly after sunset, melatonin begins to rise as we prepare for sleep.
Sadly, as we age, melatonin production lessens and sleep becomes more challenging. Many researchers believe that artificial light plays a role in the decreased production of melatonin. One study showed that just 30 minutes of exposure from an incandescent light reduces the production of melatonin by up to 40 percent.
L.E.D. lights emitted from computer screens, televisions, or cell phones are 35 percent blue light and instantly block the production of melatonin.
Strategies to keep our pineal gland healthy as we age revolve around re-establishing a lifestyle in sync with the light/dark circadian rhythms.
An Ayurvedic rule of thumb is to go to bed with absolutely no artificial or ambient light in the two hours after the sun sets, year-round. Doing so delivers more sleep in the winter and less in the summer.
A certain amount of melatonin production is needed to get us to sleep, but significantly more is needed to deliver the litany of benefits melatonin has to offer.
Melatonin is the most powerful antioxidant in the body and boosts the production of other antioxidants, such as glutathione. Melatonin is the only molecule in the body that can easily penetrate every cell in the body. It is a powerful neuroprotective and, thus, helps the nervous system recover from daily wear and tear at night while you sleep.
Even more recently, melatonin has been linked to a healthy microbiome. Melatonin production at night was linked to the proliferation of good bacteria in the gut, but not pathogenic bacteria—suggesting that melatonin helps to regulate the health and immunity found in the gut.
Excessive artificial lighting creates an “endless summer effect.” When the sun sets at 6 p.m, and we stay up until 11 p.m. using artificial light, the brain thinks it is summer. The endless summer effect increases insulin, which drives sugar into the cells, storing excess sugar into the fat cells. A decrease in melatonin due to excess artificial light also increases estrogen, which is also a growth hormone linked to weight gain in post-menopausal women.
One study showed a significant reduction in weight as measured by B.M.I. (body mass index) and better sleep in post-menopausal women who supplemented with melatonin.
As a result of the endless summer effect (from stress, shift work, aging, artificial and blue light from cell phones, TVs, and computers) nighttime melatonin levels crash, putting us all at risk. When insulin and estrogen levels rise, there is an increased risk of sugar lingering in the bloodstream for too long. Low melatonin levels decrease the production of leptin which tells the brain to keep eating, and we begin craving quick fuel in the form of carbohydrates. This effect, as well as low nocturnal melatonin levels, has been linked to an increased risk of blood sugar and cognitive concerns.
Melatonin carte blanche:
As one of the oldest molecules on the planet, melatonin has the ability to penetrate every cell of the body, and even cross the blood-brain barrier. It is the body’s most powerful free-radical scavenger and boosts the production of other powerful antioxidants in the body, glutathione and superoxide dismutase.
In one study, when supplemental melatonin was given to pregnant mothers, their levels of melatonin, glutathione, and super-oxide dismutase were increased in the brains of the fetuses within one hour. This suggests that melatonin provides powerful support for the developing brain and nervous system.
Find out your melatonin level:
Understanding the power of the light/dark cycles and respecting them with proper sleep timing should start early in life.
Melatonin levels decline as we get older, setting us up for a whole host of age-related concerns besides just sleep issues.
Before you consider supplementing with melatonin, be sure to find out what your levels actually are.
Melatonin levels are easy to measure in the urine. Within about 60 minutes, the circulating melatonin in the blood finds its way to the liver, where it is broken down into its primary metabolite, 6-sulfatoxymelatonin (MT6s). Fortunately, dried urine preserves melatonin and cortisol on urine strips. (Home urine testing for cortisol and melatonin are available here.)
While short-term use of melatonin supplementation has been shown to safely help reset circadian sleep cycles, there are still questions about long-term supplementation and whether it will suppress the production of the pineal gland’s natural melatonin secretion.
Lifestyle is the best medicine to support healthy melatonin levels.
Stay tuned for my article on how to use food to naturally build your melatonin levels back up.
Author: Dr. John Doilliard
Image: Ganosh Ganbaatar/Unsplash
Editor: Danielle Beutell