Overall Nutrition Flashcards
What is digestible energy?
=energy intake - energy lost in feces
What is metabolizable energy?
=energy intake - energy lost in feces and urine
How do we measure energy expenditure?
- Direct Calorimetry
- Indirect calorimetry
What is indirect calorimetry and how does it work?
-estimation of energy expenditure from measurements of respiratory gas exchange (oxygen consumption and CO2 production) as well as urinary nitrogen losses
What are the biological fuel values for fat, carbohydrates, protein, and ethanol?
Fat = 9kcal/gram
Carb = 4 kcal/gram
Protein = 4 kcal/gram
Ethanol = 7 kcal/gram
What is the formula for respiratory quotient?
RQ = (CO2 production / O2 consumption)
What are the respiratory quotient values for fat, carbohydrates, protein, and lipogenesis?
Fat = 0.71
Carb = 1
Protein = 0.85
Lipogenesis = >1
What do we gain from respiratory quotients?
-allows estimation of substrate utilization
What are complimentary protein sources?
-combining dietary protein sources to meet all amino acid requirements
What are fats good for?
- Fuel
- components of membrane phospholipids
- Precursors of bioactive compounds
- insulation & thermogenesis
What is “classic” essential fatty acid deficiency?
-refers to a dietary linoleic acid (18:2,-6) deficiency
What can omega 6 essential fatty acids be converted to?
- Arachidonic acid –> membranes
- Eicosanoids
what can omega 3 essential fatty acids be converted to?
- eicosanoids
- Docosahexaenoic acid –> retina and brain membranes
What is the most important monounsaturated fatty acid, and what are its benefits?
- oleic acid (18:1n-9)
- beneficial impact on blood lipids
- appears to decrease risk of CVD and Type II DM
What are the adverse effects of transfats?
-adverse effects on plasma lipid profile
