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Leptin levels decline steadily during prolonged fasting in lean children

Lorraine E Levitt Katz1, Máire Abraham, Line Johansen

  • 1Division of Endocrinology and the Division of Biostatistics and Epidemiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA. katzl@email.chop.edu

The Journal of Pediatrics
|December 2, 2006
PubMed

Insights

Serum leptin levels significantly decrease in lean children during prolonged fasting. This decline in leptin is linked to reduced insulin secretion and is observed after six hours of fasting.

Area of Science:

  • Pediatric Endocrinology
  • Metabolic Research

Background:

  • Leptin, a key hormone in energy balance, plays a role in regulating appetite and metabolism.
  • Understanding leptin dynamics during fasting is crucial for pediatric metabolic health.

Purpose of the Study:

  • To investigate the impact of fasting on serum leptin levels in lean children.
  • To explore the relationship between leptin, insulin, and other metabolic markers during fasting.

Main Methods:

  • Seventeen lean children underwent diagnostic fasts for suspected hypoglycemia.
  • Blood samples were collected at 6-hour intervals to measure leptin and various metabolic parameters.
  • Longitudinal mixed effects models were used to analyze changes in leptin over time.

Main Results:

  • Leptin levels declined significantly during fasting, averaging a decrease of 0.5 ng/mL per hour.
  • After 6 hours, leptin dropped from 15.9 ng/mL to 3.5 ng/mL.
  • Leptin levels showed a strong correlation with insulin and C-peptide over time.

Conclusions:

  • Prolonged fasting in lean children leads to a steady decline in leptin levels after 6 hours.
  • The observed decrease in leptin is likely due to the suppression of insulin secretion.
  • While baseline leptin varied with BMI and age, it showed minimal variation in the final fasting samples.
Abstract

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