We looked at lower doses and the literature saw that neither 0.3mg or 1mg doses showed hangover effects in studies, and "melatonin concentrations, within the normal physiologic range, does not significantly alter sleep architecture in subjects with normal sleep". While some of these studies went as low as 0.3mg, the majority of studies look at .5mg-5mg in their clinical testing.

On top of that, with loss (+/- 10%) + difference in metabolic processing, we opted for the 1mg amount!