Weighted blankets for improved sleep? Small study shows increase in melatonin level with use. Study duration was one day and people were young and healthy. No causal link. More investigations required.

Medical Mythbusting Commentary for October 4, 2022

Source:
Weighted blankets found to increase melatonin

Reference:
A weighted blanket increases pre-sleep salivary concentrations of melatonin in young, healthy adults