Melatonin is your body’s master sleep hormone, produced deep within your brain in a tiny gland called the pineal.
Although melatonin plays a commanding role in regulating your body’s sleep-wake cycle, also known as your circadian rhythm, it wasn’t until the early 1980s that a team of MIT researchers discovered this important connection.
Shining a Light on Natural Melatonin Production
Your body’s natural melatonin production is controlled in great part by light exposure. Your pineal gland actively produces the hormone during dark, nighttime hours and suppresses production during light, daytime hours.
In young healthy people, normal daytime blood levels of melatonin are around 10 pg/mL, and rise 15-fold to about 150 pg/mL at night. This nocturnal flood of melatonin into your system signals your body and brain that it’s time to wind down.
In response, your body becomes drowsy and falls asleep. Then sustained levels of melatonin throughout the night help ensure you get a deep, restful sleep. When melatonin levels taper off toward daylight, it signals your body to wake up.
People who produce healthy levels of melatonin tend to sleep soundly through the night and wake up feeling rested and refreshed. And growing research has shown that regular, restful sleep goes far beyond adding an energizing zip to your day. It actually revitalizes your head-to-toe good health by:
- Sharpening your memory, focus, and concentration
- Energizing your heart and cardiovascular system
- Boosting your mood and mental energy
- Increasing your capacity to deal with stress
It may also improve blood sugar balance and promote immune health. Natural melatonin production decreases drastically with age.
When you are young, your pineal gland produces plenty of melatonin but over time, the gland becomes increasingly calcified, which drastically decreases the production of this hormone.
In fact, studies indicate that around age 50, people produce 50% less melatonin than they did in their peak production ages of 8-10. And by age 70, melatonin production has dropped by a staggering 75%!
This helps explain why so many people in their mid-fifties and beyond struggle to get a good night’s rest. Often, they have enough melatonin in their bloodstream to get to sleep, but their pineal gland can only increase melatonin levels to about 30 or 40 pg/mL during the night—a far cry from the 150 pg/mL of their youth.
Other Melatonin Depleters
Although age is the primary cause of declining melatonin production, other lifestyle factors (some that go hand-in-hand with advancing age) can compound the problem, including:
- Certain prescription drugs, such as blood pressure medication, acid blockers, and anti-anxiety/anti-depression drugs
- Chronic stress
- Caffeine from coffee, soda, and even some energy drinks
So if you are one of the millions of older people who regularly wake up at two or three o’clock in the morning and lie awake in bed for a half hour or longer unable to fall back asleep, melatonin deficiency is very likely the culprit.