Human Melatonin Production Decreases With Age

TLDR

The study examined how season and demographic factors affect the amplitude of melatonin production in healthy adults. Researchers quantified overnight melatonin by measuring its urinary metabolite 6‑hydroxymelatonin from three consecutive nights in summer among 60 sex‑ and age‑balanced participants, with a winter repeat in a subgroup. Melatonin output decreased with age, while other demographic variables and seasonal timing had no significant impact.

Abstract

The purpose of this study was to investigate the effects of time of year and demographic variables on the amplitude of melatonin production in normal human subjects. Melatonin production was estimated by measuring the overnight excretion of its major urinary metabolite, 6‐hydroxymelatonin. Urine was collected on three consecutive nights in the summer from a sample of 60 normal subjects balanced for sex and age. The collections were repeated in a subgroup during the winter. Melatonin production clearly declined with age but was not influenced by other demographic variables or by season of the year.