There is so little melatonin in Lunar because research shows the benefits aren’t dose-dependent.[1] For this reason, we chose the low end of the clinically effective dosage range of melatonin.
Furthermore, taking high amounts of melatonin increases the risk of side effects like difficulty waking up and morning lethargy and grogginess.
1 http://www.ncbi.nlm.nih.gov/pubmed/23691095