what are the different levels of melatonin
In fact, melatonin production peaks around age 5 and starts a downhill slide from there. Unfortunately, we lose up to 80 percent of those original levels by the time we reach 60. And that's likely one of the reasons we don't sleep as well when we get older. When you're 20 and can easily sleep until noon, your levels of melatonin average about 80 picograms per milliliter; at 60, those levels drop down to 10. At age 20 you might have had a level of 10 in the late afternoon.