营销话术证据 A · 指南级
5-10 mg 褪黑素帮助入睡
真相
生理剂量 0.3 mg 等效；5-10 mg 过载受体 → 次日嗜睡 + 节律紊乱。
这话术为什么会流行
在美国以大剂量 OTC 出售，迎合“越多越管用”的直觉；多数人不知道有效剂量其实小得多。
机制速览
每天睡前大约两个小时, 你脑子深处开始放一种叫褪黑素 (melatonin) 的分子, 它的作用不是把你打晕睡着, 而是告诉全身: 天黑了, 该准备睡了。放它的是脑深部一个豌豆大的腺体, 叫松果体 (pineal gland)。
来源（3）
- Brzezinski, A., et al. (2005). Effects of exogenous melatonin on sleep: a meta-analysis. Sleep Medicine Reviews, 9(1), 41–50.
- Cajochen, C., Kräuchi, K., & Wirz-Justice, A. (2003). Role of melatonin in the regulation of human circadian rhythms and sleep. Journal of Neuroendocrinology, 15(4), 432-437. Review of endogenous melatonin as the internal signal of biological night: secretion is driven by the suprachiasmatic nucleus and suppressed by light, and the hormone feeds back on the SCN through MT1 and MT2 receptors, with sleep-promoting effects that track its thermoregulatory action rather than a hypnotic one.
- Chang, A. M., Aeschbach, D., Duffy, J. F., & Czeisler, C. A. (2015). Evening use of light-emitting eReaders negatively affects sleep, circadian timing, and next-morning alertness. Proceedings of the National Academy of Sciences, 112(4), 1232-1237. In a controlled in-laboratory crossover, reading from a light-emitting eReader for four hours before bed across five consecutive evenings suppressed evening melatonin, delayed circadian timing and sleep onset, reduced REM sleep, and left participants less alert the next morning, compared with reading a printed book.