- Proteins are made up of amino acids, which are the building blocks. There are 20 different amino acids, some are essential and must be obtained through diet. - The specific sequence of amino acids determines the 3D shape of a protein and its function. Denaturation occurs when proteins lose their shape due to heat, acid, etc. - Proteins serve many important functions in the body including structure, enzymes, transport, hormones, antibodies, and more. An inadequate intake can result in the body breaking down its own proteins to obtain energy.

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