Study: Obesity, Eating & Circadian Rhythm
Recent research indicates that weight gain may be more related to your body’s natural rhythm than previously thought. A recent study at Brigham and Women’s Hospital looked at the timing of 110 university students’ intake as it related to their natural circadian rhythm (sleep schedule). Melatonin is the hormone that regulates this cycle, and makes us sleepy.
The Study
To complete this research, scientists asked students to log their macronutrients, mealtimes and sleep schedules for thirty consecutive days. The participants also spent one night in a sleep lab, where researchers measured their melatonin onset (the time when melatonin secretion began), the time when they fell asleep and body composition.
The Results
Results showed that students with more body fat and/or high BMI consumed a large portion of their calories just before (within one hour of) their melatonin onset. There was no significant relationship between body composition and chronological time of meals. Macronutrient composition of the meals, caloric intake, and sleep duration were also shown to be non-significant in relation to body composition.
What It Means for Weight Loss
This study challenges the typical narrative, that eating after a certain hour contributes to obesity. Instead, it proves more relevant whether you are eating just before your natural melatonin onset (or natural bedtime). For people with highly variable schedules, or those who often ignore their natural sleepiness, this study may provide critical knowledge about how to better control their weight.