Circadian and diurnal rhythms affect food intake.
Research has suggested that meal sizes increase, and after-meal intervals and satiety ratios decrease throughout the day.
In this study, Dr John de Castro, from the University of Texas at El Paso, hypothesized that the time of food intake would relate to total intake.
Intake early in the day would reduce overall intake, while intake later in the day would tend to increase intake over the entire day.
Dr de Castro analyzed the intakes of 375 males and 492 females using 7-day diet diaries.
|Food intake in the morning was negatively correlated with overall intake.|
|Journal of Nutrition|
Food energy, the amounts ingested, and density of intake occurring during 5 4-hour periods were identified. These were compared to overall and meal intakes during the entire day.
Dr de Castro determined that the proportion of intake in the morning was negatively correlated with overall intake.
In comparison, the proportion ingested late in the evening was positively correlated with overall intake.
The energy densities of intake during all periods of the day were positively related to overall intake.
Dr de Castro concluded, "Low energy density intake during any portion of the day can reduce overall intake".
"Intake in the morning is particularly satiating and can reduce the total amount ingested for the day".
"Intake in the late night lacks satiating value and can result in greater overall daily intake".