Thread by @ck_eternity_

There seems to be an inverse relationship between melatonin and insulin, with increases is insulin reducing melatonin release, and vice versa

This is actually thought to be mediated by melatonin receptors in the pancreas, and insulin receptors in the pineal gland

This may be a large part of how eating too close to sleep can cause disrupt/worsen sleep

It's also worth noting that insulin resistance seems to create a state of chronic low melatonin production, indicating that insulin resistance may also be tied to worsened sleep

Besides reducing insulin release, melatonin may actually improve insulin sensitivity (likely through activation of AMPK)

Melatonin supplements have been used for this purpose in a few clinical trials, and IMO this is one of the more viable reasons for short term supplementation

Interestingly, there's a body of research suggesting that the body actually requires some amount of glucose for adequate melatonin production to occur

I think this is most likely because glucose increases tryptophan uptake into the brain, the precursor to serotonin and melatonin

Insomnia experienced during long fasts or on the keto diet seems to be a result of this lowered tryptophan uptake, and lowered melatonin levels

Outside of longterm low/no carb intake however, this isn't really relevant, and isn't justification for a large meal before bed