This is a fabulous paper overviewing Melatonin in the body.
Tissues produce 10-400x more melatonin than the pineal gland.
While majority knows pineal gland as the major source of melatonin, other tissues in the body also produce melatonin, including the retina, bone marrow, gastrointestinal tract, and skin.
Tissue melatonin levels follow a 24-hour cycle & are metabolically related to pineal melatonin, However, tissue melatonin levels are higher during the day compared to night, which is the opposite of pineal melatonin
Pineal melatonin acts as a systemic hormone, while tissue melatonin likely has more localised effects.
Blue light at night destroys melatonin by unbinding Melanopsin from the retinal ganglion cells.
The retina has the highest concentration of melatonin and Docosahexaenoic acid (DHA) in the body & both are oxidized by Blue light at Night.
