“Melatonin is mainly produced by the pineal gland and, although it appears not to be essential for human physiology, it is known to have a range of different effects when taken as a medication.”

Many people take a melatonin supplement as a sleep aid. However, studies show that melatonin might decrease glucose utilization and increase insulin resistance. Researchers have discovered that increasing levels of the sleep hormone melatonin reduces the ability of insulin-producing cells to release insulin. “Acute melatonin administration in humans impairs glucose tolerance in both the morning and evening.”

In my experience, melatonin raised my blood sugar! So I cannot take it. I discovered that when I had a nearly full bottle of melatonin, so I gave it to my ex-husband (he’s not diabetic)!

“Low nocturnal melatonin secretion levels are associated with an increased risk of developing type 2 diabetes.”

Finally, a detailed and fully documented article gives all the reason melatonin supplements “can lead to higher blood glucose levels and ultimately greater risk of developing type 2 diabetes.”

Even if melatonin does not raise your blood sugar, and if it helps you sleep, you still should consider it a temporary fix. Because if you take melatonin all the time, your body will eventually stop making it.


“What is melatonin?” You and Your Hormones, n.d. https://www.yourhormones.info/hormones/melatonin/ (accessed on 8/3/2020).

Rubio-Sastre, Patricia, et. al. “Acute Melatonin Administration in Humans Impairs Glucose Tolerance in Both the Morning and Evening,” Sleep. 2014 Oct 1; 37(10): 1715–1719. Published online 2014 Oct 1. doi: 10.5665/sleep.4088.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4173928/ (accessed on 8/3/2020).

Brigham and Women’s Hospital (BWH). “Study Links Diabetes Risk to Melatonin Levels,” Sleep Foundation (updated July 28, 2020). https://sleepfoundation.org/sleep-news/study-links-diabetes-risk-melatonin-levels (accessed on 8/3/2020).

Robards, Ginny. “Research Reveals a Surprising Link Between Melatonin and Type 2 Diabetes,” HumanOS (June 15, 2016). https://blog.humanos.me/research-reveals-an-odd-connection-between-melatonin-and-type-2-diabetes/ (accessed on 8/2/2020).
This can lead to higher blood glucose levels and ultimately greater risk of developing type 2 diabetes.


Melatonin, Sleep, and Type 2 Diabetes

Melatonin Use in Patients with Type 2 Diabetes and Insomnia

Type 2 diabetes: Study explains link to sleep hormone melatonin