http://articles.mercola.com/sites/articles/archive/2002/01/05/depression-part-four.aspxPeople with seasonal affective disorder (SAD) instinctively shift their melatonin levels with the seasons, paralleling the hibernation patterns of mammals. This does not appear to be true for those who don't react to shorter days and longer nights withenCommunityServer 2008.5 SP1 (Build: 31106.3070)