A signal of biological night

Melatonin & Circadian Rhythm

Melatonin secretion normally rises in darkness and is widely used as a marker of internal circadian phase.

What the evidence supports

The pineal gland is a small endocrine organ whose best-established function is rhythmic melatonin production linked to environmental light-dark information. Human pineal calcification is also a documented anatomical finding.

Where uncertainty begins

Research about calcification, melatonin and health is more nuanced than popular “detox” narratives suggest. Observational associations do not by themselves establish cause, symptoms or a treatment.

Why this matters

Understanding the underlying biology makes it easier to assess supplement and spiritual claims without dismissing personal beliefs or overstating scientific evidence.

Research sources