Metabolic Fuels Flashcards
(42 cards)
How do you calculate the caloric content of fat, carbohydrates, proteins, and alcohol in the diet?
Carbohydrate- 4 kcal/g
Protein- 4 kcal/g
Fat - 9 kcal/g
Alcohol- 7 kcal/g
What are the major metabolic fuels in the human body?
Carbohydrates - glycogen -> stored in the cytosolic granules in liver and muscle cells
Fat - triglycerides - 85% of stored fuel. 15% water. Stored in adipose tissue
Proteins - not really a food store- it provides structure and function
What does a 70 kg man store in fuels ?
Muscle glycogen - .15 kg or .4%
Liver glycogen - .08 kg or .2%
Fat - 15 kg or 85%
Protein - 6 kg or 14.5%
What is the basal metabolic rate (BMR)?
Energy required to maintain life at rest (circulation, breathing, etc.) It is based on age, sex, and weight. Dependent on lean mass, adipose tissue has lower metabolic levels and acts as an insulator.
What induces thermogenesis ?
Diet
How do BMR, physical activity, and thermogenesis contribute to the daily energy expenditure?
Daily energy expenditure composes of BMR, physical activity, diet-induced thermogenesis, wound repair and growth
What are the categories of the major nutrient groups in the diet?
Carbohydrates, fats, proteins, vitamins, minerals
What are the essential fatty acids?
4 polyunsaturated fats Linolenic acid (C18:3) - seeds, green leafy vegetables Linoleic acid (C18:2) - vegetable oils Eicosopentanoic acid (EPA, C20:5) - cold water fatty fish, yogurt, milk Docosahexaenoic acid (DHA, C22:6) - cold water fatty fish, yogurt, full fat milk
EPA and DHA are important for development of cognition and vision in young children
What are the essential amino acids?
PVT TIM HALL P= phenylalanine V= valine T= tryptophan T= Threonine I = Isoleucine M= Methionine H = Histidine A = Arginine L = Leucine L= Lysine
How many grams of proteins are required?
60 g protein/day
What happens to the excess dietary proteins?
They are not stored -> they get convert to glycogen/fat
What are vitamins?
They are organic chemicals required for growth and acquired through diet. Most are coenzymes, some are hormone receptors
What are minerals?
Calcium, magnesium, sodium, potassium, chlorine, phosphorus, sulfur,
What are the classical disease states associated with malnutrition?
Kwashiorkor
Marasmus
What is Kwashiorkor disease?
Caused by protein malnutrition. Negative nitrogen balance leads to inability to synthesize proteins. Diet has adequate caloric intake. Decreased serum proteins leads to edema (plump belly)
What is Marasmus disease?
Caused by caloric malnutrition. Diet is inadequate in caloric intake. Patient shows skin and bones
What is Body Mass Index (BMI)?
It is measured by weight/height^2 [kg/m^2]
Normal: 18.5-24.9
Overweight: 25-29.9
Obese: 30 or above
What is recommended by dietary recommendations of the “Dietary Guidelines for Americans” ?
Caloric intake much balance caloric expenditure
How does the availability of metabolic fuels change?
It depends on fed vs fasting states
What are the dietary requirements for life?
Amino acids, fats, vitamins, and minerals
What are the two mechanisms for disposing waste?
- Compounds generated by metabolism such as ammonia
- Foreign compounds taken in as food or drink that are not useful as fuel or structural components (xenobiotics)
What is ATP used for?
Chemical unit of energy that is used to fuel biosynthetic processes and physiologic processes such as nerve impulse and muscle contraction
What are the two mechanisms used to produce ATP?
Substrate-level phosphorylation - high-energy intermediates donate phosphate group
Oxidative phosphorylation - electrons are carried to form ATP
In metabolism, what is the role of oxygen
It is the final electron acceptor; oxidized fuels do not use the molecule oxygen
