Protein and Vegetarian Eating Flashcards
What are the 4 course themes?
- Evidence-based and non judgemental knowledge translation/nutrition messaging
- Nourish your body and soul (physical and mental health)
- All food fits and “how” you eat is important as what you eat (whole food approach; no 1 best diet)
- Grace and kindness
What are the functions of protein?
- Structure; growth, development, repair
- regulatory (hormones, enzymes, acid base balance, tissue/body fluid balance)
- contractile (muscle contraction)
- immunological (antibodies)
- transports (lipoproteins, transporters across cell membranes)
- energy (4kcal/g; goal is to not use it for energy though due to all of its other functions
What is there to know about individual functions of AA?
- Each amino acid has a specific function
- AA classification: eg. branched chain, sulfer
containing, acid and basic, glucogenic and ketogenic - Functions include: eg. neurotransmitters, muscle
synthesis etc.
Proteins are very specific therefore…
- if a foreign protein enters the body it is attacked
- the body learns how to make antibodies (made of protein) to attack specific protein invaders
- eg. allergies
Describe the acid base balance function of protein
- blood likes to be at a certain pH
- proteins have a negative charge on their surface
- they attract H+ ions to decrease blood acididty (e.g. thus they act as bufferes)
- they release H+ into blood if its alkaline
- extremes; acidosis or alkalosis; denatures protein and this it cannot functions e.g. hemoglobin cannot carry O2
What is the amino acid structure?
- carbon + amine group (with nitrogen) + carboxyl acid + variable side chain
What are essential amino acids?
- we have 20 AA; 9 of these are essential
- these 20 AA, in various combonations, make all the body’s proteins
What are conditional or dispensible AA?
- the body can make these AA out of other AA
- conditional means that a certain AA depends on another essential AA for it to be made
What is the primary protein structure?
- amino acid chain; AA put together in a peptide chain with peptide bonds
- dipeptide, polypeptide > 10 AA
What is the secondary protein structure?
- AA chain is now coiled
What is the tertiary protein structure?
- coiled chain is now all tangled up
What is the quaternary protein structure?
- two or more tertiary polypeptides mixed together eg. hemoglobin
Briefly describe protein synthesis
- recipe comes from the “chef” = DNA
- sends recipe mRNA who makes copies (transcription); takes it to the cooks’ assembly line = ribosomes, where the protein is made
- tRNA gets the “ingredients” = the AA from AA pool
- adds them, in order, and in a certain amount to make the final protein
- the sequence f AA determines the shape which supports a certain protein function
What is there to know about a limiting amino acid?
- if protein synthesis is under way and the code (recipe) calls for a certain AA and it is not available then protein synthesis stops
- once the missing AA is found (e.g. eaten or from breakdown of other body protein) then synthesis can continue
- the missing AA is called the limiting AA as it limits (stops) protein synthesis
We digest protein and AAs absorbed into the blood; our “AA pool” and go to be used for…
- used to build new proteins, hormones, enzymes etc.
- converted to other nitrogen containing compounds
- make non essential AA by transamination
- converted to glucose to use as fuel (gluconeogenesis)
- converted to triglycerides and stored in adipose
What is there to know about protein breakdown?
- protein in your bodu is always breaking down (turnover) in the liver; catabolism and being recycled into new proteins
- body does not store protein as it does fat and glycogen
- AA in the pool are used, turned over, stored, and excreted rather quickly
What is the dietary protein intake recommendation?
AMDR = 10-35%
Typically indicate 10-20%
- 2-3 servings of meats/a;ternatives.day
- 2 servings of dairy and alternatives
- some whole grains
- 1-1.2 protein/kg body weight
- athletes need 1.2-2 g/kg
- 1/4 of your plate protein foods
- up to 2x requirements is considered safe
Who might need more protein?
- pregnant women
- training athletes
- growing kids
- sick or trauma patients
- lower calorie diets (need 15% more) and vegetarians (need 10% more)
Why do certain people needs higher amounts of protein?
higher use of protein
nitrogen taken in > nitrogen excreted
what are the protein energy malnutritions?
kwashiorkor: protein is lacking
marasmus: overall energy and nutrients lacking