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Related Experiment Video

Updated: Jun 10, 2026

Functional Interrogation of Adult Hypothalamic Neurogenesis with Focal Radiological Inhibition

Functional Interrogation of Adult Hypothalamic Neurogenesis with Focal Radiological Inhibition

Published on: November 14, 2013

Metabolic responses on the early shift.

Heloisa Guarita Padilha¹, Cibele Aparecida Crispim, Ioná Zalcman Zimberg

¹Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, Brazil. heloguarita@rgnutri.com.br

Chronobiology International

|July 20, 2010

Summary

This summary is machine-generated.

Early morning shift workers exhibit elevated cortisol and insulin resistance (HOMA-IR) compared to night and day workers. These findings highlight potential metabolic health risks associated with early morning shift schedules.

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Last Updated: Jun 10, 2026

Functional Interrogation of Adult Hypothalamic Neurogenesis with Focal Radiological Inhibition

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Published on: November 14, 2013

Collecting Sleep, Circadian, Fatigue, and Performance Data in Complex Operational Environments

Collecting Sleep, Circadian, Fatigue, and Performance Data in Complex Operational Environments

Published on: August 8, 2019

Area of Science:

Endocrinology
Metabolic Health
Occupational Health

Background:

Shift work is linked to increased risk of metabolic disorders and obesity.
Understanding the physiological impact of different shift schedules is crucial for worker health.

Purpose of the Study:

To investigate glucose, cortisol, and insulin concentrations in fixed night, early morning, and day workers.
To explore the influence of food intake and timing of waking on these metabolic markers.

Main Methods:

Cross-sectional study comparing three groups: fixed night (n=9), early morning (n=6), and day (n=7) workers.
Food intake recorded via diary for 7 days.
Blood samples collected every 4 hours over 24 hours for analysis.

Main Results:

Early morning workers had lowest carbohydrate and highest fat/protein intake.
Elevated cortisol levels were observed in early morning workers, influenced more by time since waking.
Insulin resistance (HOMA-IR) was higher in early morning workers, particularly at 08:00h, and influenced by time-of-day.

Conclusions:

Early morning shift work is associated with higher cortisol and insulin resistance, suggesting potential metabolic health risks.
Cortisol levels appear adjusted to waking times across all shift groups.
Further attention to the health of early morning shift workers is warranted.