The goal of this application is to understand the connection between people's eating habits and the risk for developing diabetes, obesity, and cardiovascular disease.
More than a third of U.S. adults are obese (BMI greater than 30), 8-12% of adults suffer from type 2 diabetes, and up to 30% of adults have pre-diabetes. Recent research studies have suggested that it is not just what we eat, but also when we eat that may put us at risk for obesity and type 2 diabetes. Skipping breakfast and eating late at night have been associated with an increased risk for obesity and type 2 diabetes (T2D), substantiated by recent animal and human experimental studies showing that altered meal timing itself, without changes in caloric intake, can influence weight regulation and impaired glucose tolerance. This research will determine in prediabetic and non-diabetic participants whether delaying meal times worsens glucose tolerance, leads to physiological changes favoring a positive energy balance, and increases caloric intake. This research will provide mechanistic insights into the metabolic consequences of changing meal timing and may help in evidence-based approaches to improve dietary interventions in the fight against obesity and T2D.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
SINGLE
Enrollment
18
Brigham and Women's Hospital
Boston, Massachusetts, United States
Change in plasma leptin levels across sleep/wake cycle
Frequent blood samples
Time frame: During standardized meals scheduled on Days 3 and 6
Change in circadian profile of plasma leptin
Frequent blood samples
Time frame: During constant routine (Days 7-8)
Change in glucose tolerance
Frequent blood samples
Time frame: During standardized meals scheduled on Days 3 and 6
Change in circadian profile of plasma glucose levels
Frequent blood samples
Time frame: During constant routine (Days 7-8)
Change in plasma insulin levels after standardized test meal
Frequent blood samples
Time frame: During standardized meals scheduled on Days 3 and 6
Change in circadian profile of plasma insulin levels
Frequent blood samples
Time frame: During constant routine (Days 7-8)
Change in circadian phase markers, such as from core body temperature, melatonin, cortisol
Core temperature and frequent blood samples
Time frame: During constant routine (Days 7-8)
Changes circadian rhythm in resting energy expenditure
Indirect calorimetry
Time frame: During constant routine (Days 7-8)
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Change in hunger and appetite, mood, and cognitive performance
Subjective ratings and cognitive tests performed via computer interface
Time frame: Tests taken throughout the protocol, Days 1-9
Changes in microbiota, gene expression, epigenetic or proteomic markers
Frequent blood samples and saliva samples
Time frame: Throughout the protocol during Days 3 and 6, and during constant routine (Days 7-8)
Changes in sleep
Polysomnography
Time frame: Sleep will be measured during the night after Days 2 and 5
Change in insulin sensitivity, gene expression, epigenetic, lipidomic or proteomic markers from isolated adipocytes
2 fat biopsies, one sample will be taken during each protocol
Time frame: On Day 5 of each protocol