Declining melatonin levels and older people. How old is old? Graham D, McLachlan A. Journal Article 2004; 25(6): 415-418 PubMed PMID: 15665802 Keywords: Aged, Aged, 80 and over, Aging:metabolism, Analysis of Variance, Cohort Studies, Humans, Melatonin:metabolism, Middle Aged, Radioimmunoassay, Saliva:metabolism,. Citation OBJECTIVES: The purpose of this study was to investigate whether melatonin levels in older cohorts within the 'aged' population were signi..... Read abstract Full text PDF