NS 1150 Lecture Notes - Lecture 16: Antoine Lavoisier, Indirect Calorimetry, Respiratory Quotient

• School: Cornell University
• Department: Nutritional Science
• Course: NS 1150
• Professor: David Levitsky

Document Summary

Number 1 nutritional problem in the us. In college, you stop growing in height, but continue in weight: black increased most, latino, then white is least, most people get obese around 20. Change in weight=change in energy intake-change in energy expenditure. Indirect calorimetry: calorimetry-measuring calories, measure gases (oxygen consuming, co2 expelling, antoine lavoisier, 1743-1794, used guinea pigs in a cage with controlled air supply. Wanted to measure the heat they gave off. Rq= ratio of carbon dioxide blown off vs oxygen consumed= (6co2)/(6o2)=1 means you"re burning carbohydrate (yields certain amount of energy (respiratory quotient) 1 mol+80 moles o2= 56 moles of co2+h2o +8480 kcal. As rq goes up, carb burn goes up, fat burn goes down. Calculation of energy expenditure from rq: know either rate of o2 consume or rate of co2 released, rq, find the energy expended (kcal or kj) by looking it up in table.