1. Chapter 7
Proteins
and
Fats
All information presented was obtained from the
textbook Food For Today Copyright 2010 by
McGraw-Hill Companies Inc.

2. Protein
Protein helps your body
grow and repair itself.
 Found in animal
products, including
meat, poultry, fish,
eggs, and dairy
products.
◦ Also, in plant foods,
especially dry beans
and peas, nuts,
vegetables, and grain
products.
Flickr Image: Taken By Brett Jordan

3. Structure of
Proteins cell in your
Proteins are part of every
body.
 They are made of amino acids.
◦ Amino acid is a molecule that combines with
other amino acid molecules to make proteins.
◦ 20 different amino acids are found in protein
foods.
 Different proteins perform specialized tasks.
◦ Some combine an form hemoglobin.
 Hemoglobin: is a protein that transports oxygen un
the blood to all the cells in your body.

4. Protein
Digestion your food become
How does protein in
protein in your body?
◦ Your body breaks down protein into amino
acids.
◦ Amino acids combine into proteins your
body needs.
◦ Amino acids are absorbed into the
bloodstream and sent to the cells to make
new proteins.

5. Complete and
Incomplete but not all,
Your body makes some,
amino acids for itself.
◦ Essential amino acid: an amino acid that
your body needs but cannot make
◦ Complete protein: A food that contains all
9 essential amino acids.
 Meat, poultry, fish, eggs, milk, and soy
◦ Incomplete protein: food that lacks one or
more of the essential amino acids.
 Mixture of them to complete all needed amino
acids.

6. Need for
Protein roles in the
Proteins have countless
body. Here are the 5 most important:
◦ 1. Growth and maintenance
 Constantly broken down and replaced
◦ 2. Enzymes
 Chemical reactions take place in every cell in your
body. Enzymes make this possible.
◦ 3. Hormones
 Chemical messengers that help regulate the body.
◦ 4. Antibodies
 Play a role in the immune system
◦ 5. Fluid Balance

7. How much do you
need?!
 Teens should get 10 to 30 percent of their calories from
proteins.
 Adults should get 10 to 35 percent
 Example:
◦ Teens calorie requirement is 2800.
◦ What is the range of calories that this teen needs from
protein.
◦ (2800 x .10 = 280)
◦ (2800 x .30 = 840)
 Protein has 4 calories per gram
◦ Divide those each by 4 to determine the amount in grams.
◦ (70-210g)

8. Excess Protein
 Eating to much protein can be harmful
to your body.
◦ Hard on the digestive system
◦ Broken down and stored by the body as fat
 Weight gain
◦ No need for supplements with proteins or
amino acids.

9. Inadequate

Protein
Protein-energy
malnutrition (PEM)
occurs
◦ Most common form
of malnutrition in the
world.
◦ Children do not
grow properly
◦ Die of starvation
◦ Eating disorders
and addictions
Flickr Image: Taken By: Photo Plod

10. Protein Food
Choices less fat and more
Plant sources have
fiber than animal foods
◦ Usually cost less too!
 Variety
◦ Meat with plant foods
◦ Just plant foods
◦ Etc.
◦ Page. 90 examples
Flickr Image: Taken by Magic
Robot

11. The Lipid
Family
•Lipids are a family of chemical compounds found
in every cell, both in foods and in the human body.
•Two types of lipids:
•Triglyceride: is a basic fat molecule
•Main component of fatty tissue.
•Sterols: lipids found in cell membranes
•Cholesterol
Flickr Image: Taken by Jay
Mase

12. Fats
 Fats are greasy substances, with solid or
liquid, that will not dissolve in water.
◦ Liquid fats are called oils.
 High fat foods are usually high in calories
◦ Examples: butter, margarine, oils, cream, fried
foods, ice cream, nuts, egg yolks, and whole
milk.
 Visible Fats:
◦ Fats that can be seen (marbling in meat
products.)
 Invisible Fats:
◦ Cannot be seen and is a part of the chemical
composition of the food.
 Egg yolks.

13. Why Are Fats
Needed?
 Fat helps the body absorb vitamins A, D, E, and K.
 Body fat serves as an energy reserve
 Cushions and protects vital organs
 Provides warmth
 Fat is a component of cell membranes
 Help you feel full longer after eating (long digestion
time)
 Enhances the flavor of most foods
 Add moisture and tenderness, or crispiness to
foods

14. Structure of
Fats is the basic building block of
Fatty Acid:
fats.
◦ Takes three of to make a triglyceride.
 Saturated Fatty Acid: contains all the
hydrogen it can chemically hold.
◦ Usually solid at room temperature (butter,
meat fat)
 Unsaturated fatty acid: are missing
hydrogen units
◦ Monounsaturated: missing one
◦ Polyunsaturated: missing two or more
 Usually liquid at room temperature (oils)

15. Essential Fatty

Acids some,
Your body makes
but not all fats for itself.
◦ Essential fatty acid: is a
fatty acid your body
needs but does not
produce for itself, it must
be consumed.
 Omega-3 : lowers the risk of
heart disease.
 Found in: sardines, salmon, Flickr Image: Taken by malias
trout, herring, flax seeds,
kiwi, walnuts, and pumpkin
seeds

16. Fat digestion
 Fats are mainly digested in the small
intestine.
◦ Gall bladder release bile which helps to
break down the fatty acid.
 Fatty acids are absorbed into the
bloodstream- travel to the liver and
tissues that need them.
 Lipoprotein: fat-protein unit
◦ Chemical packages

17. Cholesterol
 Cholesterol: is a fatlike substance in cells
that is needed for many body processes.
◦ Helps digest fat, build cells, and make
vitamin D and hormones.
 Cholesterol circulates in the blood in two
forms:
◦ LDL: low-density lipoprotein; takes
cholesterol from the liver to wherever it is
needed in the body. LDL is known as the
“bad” cholesterol. (Build up in artery walls)
◦ HDL: High-density lipoproteins; picks up
excess cholesterol and takes it back to the
liver. HDL is known as the “good” cholesterol.

18. Diet Affects
Cholesterol
Saturated Fat
◦ Raise the level of LDL cholesterol
◦ Meat, Poultry skin, whole-milk, tropical oils
(coconut oil)
 Polyunsaturated Fat
◦ Help lower cholesterol levels if used in place
of saturated fats.
◦ Vegetable oils, corn oil, soybean oil
 Monounsaturated Fat
◦ Lower levels of LDL and Raise levels of HDL
 Olives, avocados, nuts, peanut oil, and canola oil.

19. Trans Fats
 Hydrogenation: turns vegetable oils into
solids.
◦ The missing hydrogen is added to the
unsaturated fats, which increases saturation.
 Shortening and most margarines
 Longer shelf-life and extra flavor
 Trans-Fats: hydrogenation forms fatty
acids
◦ Increase LDL levels and lower HDL levels
 Salad dressings, snack food, baked goods, fast
foods, and crackers

20. How many calories
of fat?
 Most Americans eat TOO much fat;
especially saturated fat.
◦ Increase of heart disease, and cancer
 You NEED fat in your diet, just in
moderation.
◦ Teens need 25-35 percent of their caloric
intake
◦ Adults need 20-35 percent of their caloric
intake

21. Controlling Fat
 Eat plenty of fruits, vegetables, and whole-grain
products
 Choose fat-free or low-fat milk
 Remove skin from chicken and turkey
 Chose lean cuts of meat- trim fat and drain
grease
 Watch portion sizes
 Chose fish or lean poultry over red meat
 Limit fried foods
 Avoid trans-fats

22. Resources
 Information
◦ All information presented was obtained from the textbook Food
For Today Copyright 2010 by McGraw-Hill Companies Inc.
 Photographs
◦ Slide 2: Flickr Image: Taken By Brett Jordan
◦ http://www.flickr.com/photos/x1brett/3459052829/sizes/s/in/photos
tream/
◦ Slide 9: Flickr Image: Taken By: Photo Plod
http://www.flickr.com/photos/photoplod/5316022392/sizes/s/in/pho
tostream/
◦ Slide 10: Flickr Image: Taken by Magic Robot
http://www.flickr.com/photos/magicrobot/3157414088/sizes/m/in/p
hotostream/
◦ Slide 11: Flickr Image: Taken by Jay Mase
http://www.flickr.com/photos/jaymasephotography/5381332769/si
zes/s/in/photostream/
◦ Slide 15: Flickr Image: Taken by malias
http://www.flickr.com/photos/malias/375664720/sizes/m/in/photost
ream