Can Melatonin Guarantee Better Sleep? Insights on Insomnia

Author: Ma Jie, Director of the Health Preservation Center at the Second Hospital of Traditional Chinese Medicine in Sichuan Province, Chief Physician of Integrated Traditional and Western Medicine. Reviewer: Sun Shucheng, Chief Physician of the Department of Otolaryngology at Guang'anmen Hospital of the China Academy of Chinese Medical Sciences; President of the Sleep Medicine Professional Committee of the World Federation of Chinese Medicine Societies. Produced by: Scientia China. The cover image of this article is sourced from a copyright-free image library. Reproducing content may lead to copyright disputes.

"Unable to sleep at night and struggle to wake up during the day" is a reality for many people. According to the latest survey by the Chinese Sleep Research Society, over 300 million people in China suffer from sleep disorders, and sleep issues have become an increasingly serious public concern.

Compared to men, women experience hormonal changes throughout their physiological stages that make them more susceptible to sleep disorders. For instance, during menstruation, women often encounter more sleep disturbances than usual. Moreover, long-term insomnia in women can result in endocrine disorders, leading to symptoms such as dull skin, pigmentation, increased wrinkles, and even a decline in ovarian function, which accelerates aging and creates a vicious cycle.

It is crucial to differentiate between staying up late and insomnia. Staying up late is a subjective decision to remain awake, resulting in insufficient sleep. In contrast, insomnia is characterized by an inability to fall asleep, which is a passive form of "staying up late," often stemming from mental anxiety.

In modern society, the pace of life is fast, and an increasing number of young people are facing sleep difficulties due to pressure and anxiety. This is manifested in symptoms such as trouble falling asleep, frequent dreaming and waking, and difficulties returning to sleep after waking.

The issue of insomnia has become a pressing need, resulting in the emergence of various sleep aids, including sleep pillows, sleep sprays, eye masks, essential oils, foot soaks, and white noise machines. Among these, the most popular supplement is undoubtedly melatonin, often referred to as the "miracle drug for insomnia."

Many individuals report that after taking melatonin, they find it much easier to fall asleep and their sleep quality improves. So, is melatonin truly that miraculous? Are there side effects associated with it? Could it lead to dependency? To answer these questions, we must first understand what melatonin is.

Melatonin can regulate sleep.

Melatonin is a hormone produced by the pineal gland in the human body and is closely related to our biological clock, with its secretion following a circadian rhythm.

The secretion of melatonin is affected by light. During bright daylight hours, melatonin secretion is suppressed, keeping individuals alert. However, as night falls and darkness envelops the environment, melatonin secretion is stimulated, leading to natural sleep.

Melatonin does not function like sleeping pills; it doesn't force you into a deep sleep. Instead, it serves as a cue, "reminding" your body that it's evening, encouraging it to relax and prepare for sleep. Consequently, you won't experience grogginess or headaches the following day.

In light of this, many related products have emerged on the market, particularly exogenous melatonin supplements, which have become star products in the sleep industry.

Is melatonin harmful to the body?

Can excessive consumption of melatonin lead to addiction?

In our country, melatonin is regarded as a health supplement and is not classified as a controlled substance. When used within recommended limits, it does not lead to addiction, and discontinuation does not yield withdrawal symptoms or severe side effects. However, at high doses, melatonin may cause adverse reactions, including headaches, confusion, and fragmented sleep.

Does melatonin impact fertility?

As a hormone, melatonin has been rumored to potentially cause endocrine disorders when used excessively over long periods, which could raise prolactin levels, inhibit ovulation, and affect fertility.

Current research has not confirmed that long-term high dosage of melatonin has adverse effects on fertility, but the potential risks remain uncertain, making it advisable to avoid excessive long-term use.

How should one choose and take melatonin?

For melatonin, the recommended daily dosage in our country is 1 to 3 mg. If you choose to take it, avoid purchasing high-dose products, and opt for domestic brands, as foreign brands may have dosages that are too high for the Chinese populace.

In fact, a dosage of 0.1 to 0.3 mg of melatonin can aid sleep, while a dosage of 0.3 to 0.5 mg can help regulate circadian rhythms. Higher doses do not necessarily enhance sleep-promoting effects and may increase the risk of overdose. It is advisable to use it under a doctor’s supervision.

Melatonin is not a universal cure for insomnia.

Although melatonin can regulate sleep, there is currently a lack of large sample data and high-quality evidence concerning its effectiveness in improving sleep and its specific mechanisms of action. Therefore, its application for treating insomnia is not recommended in clinical practice.

Based on approved indications both domestically and internationally, melatonin usage is more suitable for two types of individuals.

1. Regulating circadian rhythms.

When it’s time for sleep, insufficient melatonin secretion can hinder our ability to sleep. This typically occurs in people experiencing jet lag, working night shifts, or those who usually stay up late and wish to sleep earlier. In these instances, the biological clock hasn’t adjusted, affecting the melatonin secretion cycle. Adjusting the melatonin secretion cycle requires time, and in such cases, moderate melatonin intake may help alleviate jet lag symptoms.

2. Regulating sleep for the elderly.

As individuals age, melatonin secretion diminishes, so older adults can take melatonin in moderate amounts to assist with sleep. However, the majority of sleep quality issues are not solely due to decreased melatonin secretion. In other words, melatonin assists in gradually adjusting biological rhythms but is not effective for all patients suffering from insomnia. When insomnia is linked to anxiety, addressing the anxiety must be prioritized for the insomnia to improve. If insomnia persists for a prolonged period without relief, it is crucial to consult a doctor promptly.