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Measuring Dim Light Melatonin Onset in Humans.

Melissa A St Hilaire1,2, Steven W Lockley3,4,5

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Summary
This summary is machine-generated.

The human circadian clock is timed by the pineal melatonin rhythm. Dim light melatonin onset (DLMO) is a key marker, and this chapter details its measurement from plasma and saliva.

Keywords:
CircadianDim lightHumanMelatoninPlasmaSalivaSerum

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Area of Science:

  • Chronobiology
  • Endocrinology
  • Sleep Science

Background:

  • The human circadian system relies on internal biological rhythms.
  • The pineal melatonin rhythm is a critical indicator of the body's internal clock timing.
  • Dim light melatonin onset (DLMO) serves as a gold-standard marker for the central circadian clock.

Purpose of the Study:

  • To outline standardized procedures for collecting melatonin samples.
  • To explain the methodology for calculating DLMO from plasma and saliva.
  • To ensure accurate assessment of the human circadian clock timing.

Main Methods:

  • Detailed protocols for collecting plasma and salivary melatonin samples.
  • Description of the threshold method for DLMO calculation.
  • Guidelines for controlled dim light conditions during sample collection.

Main Results:

  • Established criteria for reliable melatonin sample collection.
  • A defined threshold method for accurate DLMO determination.
  • Validated procedures for using DLMO as a circadian marker.

Conclusions:

  • Accurate DLMO measurement is essential for understanding circadian timing.
  • Standardized protocols ensure the reliability of DLMO as a biological marker.
  • This chapter provides a practical guide for researchers and clinicians.