Nutrition Of Macronutrients Flashcards
What two vies can nutrition be viewed from?
Food-based view
- behaviors and what people should do
Metabolic view
- dietary mechanisms
What are the essential amino acids?
Thr, trp, Val, leu, lys, ileu, met, phe, his
What are the essential lipids?
Linoleic acid
Linolenic acid
What is the metabolic fate/end point for all three macro nutrients?
Carbs = water, CO2 and ATP
Protein = water, CO2, ATP and Nitrogen
Lipids = water, CO2 and ATP
What are the daily recommendations for carbs, proteins and lipids
Carbs = 45-65% total calories
- minimum of 130 g CHO/day
- added sugars = less than 10% of total kcal if not less
- dietary fiber = 25 and 38 g for females and males respectively
Protein = 0.8 g/kg per body weight
Lipids = 20-35% total kcal
- sat fat = less than 10% of total kcal if not less
- trans fats = as close to 0 as possible
How much energy (kcal) does each macronutrient produce?
Carbs = 4 kcal/g
Protein = 4 kcal/g
Lipid = 9 kcal/g
Simple vs complex carbohydrates
Simple = 1/2 carbohydrate units
- monosaccharides and disaccharides
Complex = 3-20 sugar units
- oligosaccrharides and polysaccharides
Most common monosaccharides
Glucose
Fructose
Galactose
Most common disaccharides
Maltose
Sucrose
Lactose
Most common polysaccharides
Starch
Glycogen
Cellulose
At what range is the cut off for ketosis?
50g
- anything less and your in ketosis
How does acetyl CoA usage change with respect to glucose/carbohydrate intake
Adequate intake = Oxaloacetic acid (OAA) is formed in proper numbers
- Acetyl CoA and OAA enter TCA and produce ATP
Inadequate intake = OAA is not produced in proper numbers
- Acetyl CoA forms ketone bodies instead (acetone/acetoacetate, etc)
- ketone bodies can be used as fuel for ATP, but too high concentrations can mess up acid-base concentrations
Gluconeogenesis
Occurs in liver and small amounts in kidney
- is de novo synthesis and not glycolysis in reverse
What 3 amino acids are needed for gluconeogenesis to occur?
Ala, pro, ser
What are the 2 semiessential amino acids?
Cysteine (Cys)
- if large amounts of MET are present, can be synthesized de novo
Tyrosine (Tyr)
- if large amounts of phenylalanine (phe) are present, can be synthesized de novo