How has melatonin supplement use changed in the US from 1999 to 2018?

Reported prevalence and usage trends of melatonin supplements among US adults were systematically examined over a twenty-year period spanning from 1999 through 2018, providing a descriptive overview of consumption patterns without assessing health outcomes or biological mechanisms. This longitudinal tracking focuses exclusively on aggregate survey responses to capture temporal shifts in supplement adoption across the general adult population.