Using Melatonin for Sleep

Melatonin is a natural hormone the body produces when daylight begins to fade. It plays a key role in our ability to get restful sleep. Our bodies rely heavily on adequate levels of melatonin for maintaining a healthy circadian rhythm. Even small disruptions in normal levels of melatonin can cause insomnia and excessive daytime fatigue.

Low levels of melatonin, or disruptions in the production or absorption of melatonin, are associated not only with insomnia, but other disorders too, including jetlag, shift work sleep disorder, and delayed phase sleep disorder.

Fortunately, using melatonin supplements for sleep delivers refreshing, rejuvenating rest, while putting the circadian rhythm back in natural sync.

How Does Light Affect Melatonin and Sleep?

Melatonin supplements are useful for occasional insomnia, but it’s also able to help with more frequent problems associated with circadian rhythm. More on that below.

Circadian rhythm—our daily waking and sleeping cycle—is largely controlled by the amount and intensity of light we receive, which determines how much melatonin our brains produce. As light levels change, melatonin levels also fluctuate.

When light levels decrease as the day progresses toward evening, the brain starts increasing its production of melatonin. Increased levels of melatonin kick off the processes that prepare us for sleep. However, these processes are not instantaneous.

The Biology of Melatonin, Sleep, and the Circadian Rhythm

First, let’s have a look at the eyes, where the process begins.

The amount and intensity of light we get is the external cue that sets our body’s internal clock, which is made up of specialized structures in the brain, as well as nerve fibers in the eyes.

Although sunlight appears white, natural sunlight is composed of different wavelengths of light, with violet and blue wavelengths being the most energetic. They have a powerful effect on a special type of light receptor in the retina of the eye called the melanopsin retinal ganglion cells (MRG cells). MRG cells are particularly sensitive to wavelengths of light in the more intense violet-to-blue portion of the spectrum.

When stimulated by plentiful blue light, the MRG cells send signals to the hypothalamus in the brain, which controls circadian rhythm. These signals prevent the hypothalamus from telling the pineal gland, also in the brain, to produce melatonin.

But as the bluer, more intense rays of the sun begin to fade in mid-afternoon, MRG cells become less active and send fewer signals. Now that the hypothalamus is no longer being signaled, it stops preventing the pineal gland from making melatonin. This results in the pineal gland ramping up its production of melatonin, preparing the body for sleep.

If that seems like a large set of steps and conditions for the nervous system to put us to sleep, it is. When it comes to sleep, our nervous systems can’t turn on a dime. Sleep results from the body summing up many different conditions and inputs, which all come down to whether melatonin levels tell us it is time to go to bed.

That’s why it’s critical to start preparing for sleep a few hours before you’re ready to turn the lights out. One way to do that is to add melatonin supplements to your nightly routine.

Using Melatonin Supplements for Sleep

According to research from Johns Hopkins, melatonin supplements are helpful in returning the body’s melatonin levels back to normal effectively and safely.

There’s research-based evidence that melatonin supplements help alleviate the following conditions:

• Insomnia. Studies indicate that oral melatonin supplements reduce the length of time it takes for people to fall asleep, especially for those suffering from melatonin deficiency. Melatonin deficiency is particularly common in adults past 50 and can be treated successfully with oral melatonin supplementation in the 0.5 milligram (mg) to 5 mg range.
• Delayed sleep phase disorder (delayed sleep-wake phase sleep disorder). Melatonin has been found to be particularly helpful in treating delayed sleep phase disorder, a condition in which people fall asleep and wake up at least two hours later than normal. It’s thought this disorder is caused by a neurological insensitivity to melatonin. Melatonin supplements help reset the individual’s circadian rhythm.
• Jet lag. Research has shown melatonin supplements reduce daytime sleepiness and other symptoms of jetlag.
• Shift work sleep disorder.  Shift work sleep disorder is common among those who work afternoon to late evening and evening to morning shifts. Melatonin supplements have been found repeatedly in research studies to help alleviate shift work sleep disorder.

Melatonin is non-narcotic and not addictive. Unlike other sleeping aids, it’s not an abrupt on/off switch for consciousness. Rather, it’s in charge of starting the body’s process of winding down and transitioning to a state of restful relaxation and sleep.

**Do not use melatonin if you are pregnant or breastfeeding or have an autoimmune disorder, a seizure disorder or depression. Talk to your health care provider if you have diabetes or high blood pressure.**

Works Cited

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