Most people in Taiwan suffer from sleep problems, and many sleep aid suggestions are circulating online, with "drinking warm milk" before bed being one of them. However, experts point out that while the claim "milk contains tryptophan, which can synthesize melatonin and help with sleep" is not wrong, it would take drinking "2500cc of milk" to truly affect sleep.

Clinical psychologist Li Wei-Kang previously posted on Instagram that tryptophan is a precursor to serotonin, and serotonin can also be converted into melatonin. Both help stabilize sleep. However, 100cc of milk only contains 0.042g of tryptophan, and at least 1g of tryptophan is needed to affect sleep, which means drinking 2500cc of milk would be necessary.

It's unlikely that an average person would chug 2500cc of milk before bed. He believes that the effect of milk might come from the experience linked to ritualistic behavior, such as relaxation, storytelling, home, mother, or wanting to sleep. This also explains why some people drink milk before bed and don't experience any sleep-inducing effects, as not everyone drank milk before bed as a child. Li Wei-Kang reminds that if you want to rely on milk for sleep, remember to choose warm milk, "because your parents probably wouldn't have given you cold milk as a child."

Furthermore, surgeon Dr. Chiang Kuan-Chun also said that while milk is rich in tryptophan, and the statement that "it is the raw material for the brain to synthesize sleep-aiding melatonin" is not wrong, it takes at least 5 to 6 hours for the human body to supplement milk protein, break it down into amino acids for absorption, enter the brain's "blood-brain barrier" to secrete serotonin, and then synthesize melatonin. If relying on warm milk for sleep, one might only fall asleep around 5 or 6 in the morning.

He also suggested that drinking warm water before bed might be slightly healthier than warm milk, as drinking warm milk before bed could lead to cavities or too many calories. "If drinking something warm can help the body relax, then replacing warm milk with warm water might have the same benefit."

In addition, thoracic and critical care specialist Dr. Huang Hsuan also explained that most sleep-aiding foods contain a sleep-aiding substance called "tryptophan," which is one of the essential amino acids for the human body. The human body cannot synthesize it and must obtain it from food. Tryptophan is converted into another substance called "serotonin" in the human body. Serotonin is also a precursor to melatonin; when melatonin secretion increases, it induces sleep. The placebo effect, routine pre-sleep activities, and drinking warm beverages could all be factors why drinking warm milk makes sleep better. In fact, "drinking a cup of warm water before bed" might have the same effect as drinking warm chocolate and can also help with sleep quality.

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