Vol. 25 (6) 2004 Neuro endocrinology letters

Declining melatonin levels and older people. How old is old?

OBJECTIVES: The purpose of this study was to investigate whether melatonin levels in older cohorts within the 'aged' population were significantly lower than in younger 'aged' individuals and hence point to a possible confound in cross-sectional studies which group individuals over 55 in one category.

SETTING AND DESIGN:<.....