Impact of meal timing and frequency on the twenty-four-hour leptin rhythm.
OBJECTIVE
To study the influence of changes in meal timing and frequency on the diurnal rhythm of leptin and on the 24-hour profile of insulin and glucose.


METHODS
Five obese women were studied twice during a weight-maintaining diet in either 3 daily or 8 day and night equal portions. Blood was sampled for 24-hour profiles of leptin and insulin.


RESULTS
During the 8-meal intervention, the 24-hour rhythm of leptin changed significantly: the amplitude decreased (p = 0.0089) and the acrophase was delayed by 168 min (p = 0.021). Also, 8 small insulin secretion peaks occurred instead of the 3 postprandial high insulin peaks.


CONCLUSIONS
The dispersion of food intake over 24 h affects the diurnal leptin rhythm. These changes could not be attributed to changes in circadian timing or energy balance. Instead, changes in daily insulin secretion profiles might play a role.
Fogteloo
A J
AJ
Department of General Internal Medicine, Leiden University Medical Center, Leiden, The Netherlands. a.j.fogteloo@hotmail.com
Pijl
H
H
Roelfsema
F
F
Frölich
M
M
Meinders
A E
AE
D000328:Adult; D001786:Blood Glucose / Q000378:metabolism; D002940:Circadian Rhythm / Q000502:physiology*; D016000:Cluster Analysis; D004734:Energy Metabolism / Q000502:physiology; D005247:Feeding Behavior / Q000502:physiology*; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D020738:Leptin / Q000097:blood*; D009765:Obesity / Q000097:blood*
D001786:Blood Glucose; D007328:Insulin; D020738:Leptin