Sleep and Weight Management: A Surprising Relationship
Presented by Dale Schoeller and Michele Ravelli: UWBC Isotope Ratio Mass Spectrometry Lab
The Isotope Ratio Lab is limited to the measurement of molecular weights of <100 and is a fraction of the majority of biomolecules. What we do offer, however, is unprecedented precision for the measurement of isotope abundances. The isotope ratio of the 18O/ 16O isotope in water averages 0.002000 but the precision is 0.00000002 enabling us to trace small amounts of expensive H218O water in the human body. The Isotope Ratio Lab has been at the forefront of measuring human energy expenditure using the doubly labeled method to measure human energy expenditure and, more recently, energy intake. The measurement of energy expenditure has provided evidence opposing the hypothesis that low energy expenditure is a cause of obesity and that sleep elongation in individuals who chronically sleep only 6 ½ hours per night leads to an unprescribed reduction of energy intake of 270 kcal/d under conditions of daily living. These two tools are reshaping obesity research.