proteins

1. Proteins, Amino Acids
• About 20% of total body weight =
protein
• Contain -

2. Amino Acids =
• Smallest building blocks of proteins
• 20 different amino acids:
• -
• -

3. Essential Amino Acids =
• Body can NOT make them at all or
• can NOT make them in sufficient
quantities for normal health

4. Non-essential Amino Acids =
• Body CAN make them from
carbohydrate, fat and a nitrogen source

5. Amino Acids are “strung” together
to make proteins:
• Different Proteins consist of:
– 1)
– 2)
R A B D E

6. The amino acids and their sequence
determines:
- the folding and 3-dimensional shape
of the protein
- The 3-dimensional shape dictates the
function of the protein

7. Protein Denaturation:
• A protein subject to heat, acid, alcohol
looses its original 3-d shape (it unfolds)

8. Functions of Proteins:
• 1) Building material
• 2) All Enzymes
• 3) Some Hormones

9. Functions of Proteins:
• 4) Antibodies
• 5) Fluid Balance
• 6) Acid-Base Balance

10. Functions of Proteins:
• 7) Transport Proteins
• 8) Structural Components
• 9) Neurotransmitters
• 10) Energy

11. Body’s 1st Priority =
supply Energy to all cells:
If Insufficient CHO or fat
Then sacrifice your own body
protein to make energy

12. Protein Needs Increased:
• 1) Pregnancy
• 2) Growth, (Children, Infants)
• 3) Lactation
• 4) Injury, illness
• 5) Exercise

13. When making proteins in body:
NEAA
EAA
EAA
EAA
NEAA
EAA
EAA-NEAA-EAA-NEAA-EAA-EAA-NEAA -NEAA
NEAA
NEAA EAA
EAA
NEAA
NEAA
NEAA
EAA
EAA
NEAA
EAA
X

14. Complete Protein vs. Incomplete Protein
• 1)
• 2)
• 3)
• 4)
• 1)
• 2)
• 3)

15. Complementary Proteins:
• Can make plant protein complete by:
• 1)
• 2)
• Combine at least 2 of the following 3 groups:
– 1)
– 2)
– 3)

17. Rating Protein Quality:
• 1) Does it provide all EAA’s, in correct
proportion?
– Animal proteins =
– Plant proteins =
• 2) How well is it Digested and Absorbed?
– Animal protein
– Bean protein
– Grain protein

18. Protein Rating:
• Egg white 100
• human breast milk 100
• Beef 100
• Milk protein 100
• Tuna 100
• Soybean 94
• Chickpeas 69
• Kidney beans 68
• Rolled oats 57
• Lentils 52
• Whole wheat 40

19. How to calculate your protein needs:
• Based on desirable body weight
• Based on consumption of mostly animal
protein
• Adults:
• If consuming large % of plant protein need
more

20. Food Label Protein Information:
• The % Daily Value depends on whether the
food item is animal or plant protein
• Average adult:
– If Animal Protein:
– If Plant Protein:

21. % Daily Value Calculation:
depends on whether food is animal or plant protein
• If animal protein = • If plant protein =

22. Chili w/ meat vs. Chili w/ Beans
• Protein 12 g
• % Daily Value =
• Protein 15 g
• % Daily Value =

23. Upper limit of Protein Intake:
• RDA upper limit =

24. Excess Protein Intake:
• Xs protein ---> increases B6 needs
• Pregnant women and infants on xs protein
supplements ---> increased Zn excretion in urine
• Infants xs protein ---> deficits in cognitive
development
• Xs protein ---> increased Ca++ excretion in urine

25. Excess Protein Intake:
• Average American adult consumes about 90
g protein daily
• 70% of this protein comes from animal
flesh and dairy products