The effect of gender on the melatonin suppression by light: A dose response relationship

Abstract

It is well known that light is an inhibitor of pineal melatonin secretion in humans. However, the effect of gender on the melatonin suppression by dim and bright light is still controversial. The present study investigated the effect of gender on the suppression of melatonin at five light intensities (0, 200, 500, 1000, 3000 lux). Five healthy men and women attended five testing sessions separated by one week. At each session, subjects were exposed to light from midnight to 0100 hours in a sitting position. Blood samples where collected at regular intervals and plasma melatonin concentration was measured using a specific radioimmunoassay. No gender differences were found in melatonin suppres..