Have you ever wondered why your body is naturally awake during the day and asleep during the night? Can the body tell day from night? The reason behind this lies in the body’s natural ability to set its own pace according to the time of day or night. Our body secretes the hormone called melatonin which helps the body determine whether it is time to wake up or time to sleep. In this article, we will discuss how this natural process works as well as how it is related to sleep.
Melatonin is a serotonin-derived hormone made by the pineal gland and aids in the modulation of sleep patterns in circadian and seasonal rhythms. This hormone helps control your sleep-wake cycles.
The major triggering factors of the pineal’s activity are light and darkness. During the day where natural light is abundant, the pineal is inactive; as soon as the sun sets and darkness starts to envelop the environment, the pineal gland is activated and starts to produce melatonin and release it into the blood.
How does the body know whether it is daytime or nighttime? The body has a natural body clock; in scientific language, this is that part of the hypothalamus called the suprachiasmatic nucleus (SCN). The exposure to natural light in the morning stimulates a nerve pathway in the retina which then sends signals to the SCN which in turn gives the signal to raise body temperature and reduce the amount of melatonin the body makes. In the same way, at sunset, the retina detects that there is less natural light (or none), so it gives the same signal to the SCN which will then signal the body to start releasing melatonin. The level of melatonin in the body steadily increases as the night deepens and is significantly elevated around 9 p.m. The melatonin level remains elevated for hours through the night until before the break of a new day when melatonin shall start to drop around (4 a.m.). Melatonin is relatively undetectable during the day.
The presence or absence of light is what adjusts the body clock and triggers the production of melatonin. So even during daytime, the melatonin level remains elevated if the person is in a dimly lit environment; even during nighttime, the release of melatonin to the blood is inhibited if there is bright artificial lighting.
Melatonin is not a sedative but is a cue for the body that it is nighttime (or daytime) and therefore induces the onset of sleep to an individual. During the night when the melatonin level is at its peak, the person will start to lose focus, the body temperature will start to rise, production of cortisol is delayed, and the body is prepared for sleep.
There are some people who experience an improvement in their sleep quality with the help of melatonin; however, research data does not show that melatonin can effectively act as a “sleeping pill.” It can, however, successfully adjust the body clock of an individual. Melatonin has been proven to help the blind as well as people with insomnia, jet lag, and sleep problems related to shift work, provided there is correct administration and the appropriate dosage is taken.
Melatonin is not abundant in food such as fruits, vegetables, grains, and meats; as a person ages, natural melatonin levels will also start to decrease. There are adults who produce little or even no melatonin at all.
Taking melatonin supplements becomes a practical option. Melatonin supplements can be taken in liquid or pill form and is safe when taken in small regulated doses whether for short- or long-term use. In the US, this can be purchased over the counter, and no other hormone can be purchased without prescription except melatonin. These do not need FDA approval nor is it being regulated in a pharmaceutical level as what is done for other drugs.
With any kind of supplement, however, it is highly recommended that you talk to your doctor before taking them, especially children as well as pregnant and nursing women
Studies have shown the following good uses of melatonin supplements:
While melatonin supplements have their benefits and uses, these can have the following negative side effects.
When you experience these side effects, make sure that you will also adjust your activities accordingly. For example, if you are experiencing unusual sleepiness, it is best that you refrain from driving any type of vehicle or operate any kind of machinery.
These side effects are found to go away once the melatonin supplementation is stopped. Discuss with your doctor what other options you can take as an alternative to melatonin supplements.
Clinical studies on melatonin are not yet very conclusive. The abovementioned uses, benefits, and side effects are quite subjective in terms of how melatonin is taken, what time of day or night it is taken, how much of it is taken, who is taking it, and for what reason it is being taken.
Melatonin as a cure is not yet confirmed, although some studies indicate that melatonin might be useful in fighting infectious diseases including bacterial infections, viral infections like HIV, and even as a treatment for cancer.
If you have sleep disorders or health conditions that you would like to be addressed, and you think melatonin can be of help to you, do not hesitate to discuss this with your doctor. Health professionals are still the most reliable persons to talk about these health issues.