Transcript NutrientsandMetabolism

“You are what you eat!”
The 6 Essential Nutrients
Fats
Vitamins
Protein
Essential
Nutrients
Carbs
Minerals
Water
Nutrients vs. Cal/g
•
Calorie- is a measure of heat. It is usually abbreviated as kcal, kc,
C, or capitalized as Calorie.
1 gram of Carbs = 4 Calories
1 gram of FAT = 9 Calories
1 gram of Protein = 4 Calories
Calorie Calculation
Carbs: 22 grams x 4 Calories/gram = 88 Calories
Fat: 3 grams x 9 Calories/gram = 27 Calories
Protein: 2 grams x 4 Calories/gram = 8 Calories
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TOTAL Calories: 123 kcals
ARE YOU IN
RIGHT
?
ATP PRODUCTION
High intensity activity
Glucose
Fatty Acids
Amino Acids
Low intensity activity
ROLE OF CHOs IN THE BODY
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Energy source (high intensity exercise)
Protein sparing
Metabolic primer for fat metabolism
Fuel for the central nervous system
Bulk (fiber)
SIMPLE CHOS
COMPLEX CHOS
Increase Preferred
High Carbohydrate Foods
Keep Intake of Unpreferred
High Carbohydrate Foods to a
Minimum
Dietary Fiber
• Water-Insoluble Fiber
– Prevents the big “C”!
– Water-soluble Fiber
– May reduce serum
cholesterol
RNA: 20 to 35 g/day
(3:1 ratio water-insoluble to
water-soluble)
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Wheat Bran
Whole Grain
Popcorn
Nuts & Seeds
Skins on Frts. & Vegs
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Oats & Barley
Brown Rice
Legumes
Peas & carrots
Flaxseed
Psyllium
Some Frts. & Vegs.
Types of CHOs
PRIMARY SOURCE OF ENERGY DURING EXERCISE
Animal Polysaccharide
Glycogen:
G
G
G
STRING
G
G
G
G
G
GLYCOGEN
G
Is the chief storage
Form of CHO in
Animals: it is stored
Primarily in the liver
And muscles.
MUSCLE
GLYCOGEN
Fuel for
muscles
Fuel for
the brain
and muscles
LIVER
GLYCOGEN
BLOOD GLUCOSE
ENERGY RELEASED FROM
SUGAR
-Sugary foods such as fruit,
Fruit juices, candy, or soda pop,
Eaten in place of a meal cause a
Quick rise in blood sugar and
Energy
Meal eaten an energy
Released from sugar
-About an hour later blood
Sugar and energy decline rapidly,
Bringing on symptoms of
Hunger.
Energy Released From Sugar,
Starch, Protein, & Fats
Energy Release
Meal eaten &
Energy
Energy released
Released from
From sugar & starch
protein
Energy
released
from fat
ARE ALL CHO’s
PHYSIOLOGICALLY EQUAL?
Faster Rate of glucose absorption into the
blood
Slower rate of glucose absorption into the
blood
Glycemic Index of some Popular foods
90
80
70
60
50
40
30
20
10
0
Gatorade
High GI: >60
Jelly Beans
Mars Bar
Bran Muffin
Mod GI: 40-59
Baked beans
Spaghetti
Yogurt
Lentils
Low GI: <40
Protein Functions
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Major structural component
Growth, repair and maintenance
Transporter (lipoproteins)
Antibodies- disease protection
Blood osmotic pressure
Produces hemoglobin, enzymes, and hormones
Energy (5-10%)
PROTEIN
Nonessential AAs
(can be synthesized in the body)
Essential AAs
(cannot be synthesized in the body)
Quality Makes The Protein
Complete Protein (ANIMAL)
(Contains all the essential AAs)
Incomplete Protein (PLANT)
(Do not supply all the essential AAs)
(EXCEPT SOYBEANS… contain all the essential AAs)
CONTRIBUTION OF MAJOR FOOD GROUPS TO
PROTEIN CONTENT OF TYPICAL AMERICAN
DIET
45
40
35
30
25
20
15
10
5
0
Meat
Ceral
Dairy
Products
Nuts
Fruits,
vegetables
Fats, oils
Substitute Lean Protein for Fatty
Protein
RDA for Protein
Average adolescent/ adult
BW
Growing children
Athletes in heavy training
BW
training)
Amino (aerobic
acid supplements
Special considerations
-0.8 grams/ kg
-2.0- 4.0 grams/kg BW
-1.2- 1.8 grams/ kg
- not recommended
-vegetarian athletes
-Those on very low fat
or low calorie diets
-Athletes avoiding
meat for “health reasons”
Contribution of Protein to Energy Metabolism
at Various Intensities of Exercise
7
6
5
4
Percentage of
Contribution
3
2
1
0
Rest
High (sprint)
PROTEIN USE DURING
EXERCISE
Why protein constitutes a limited fuel in exercise:
• Studies have shown only minimal protein
breakdown during endurance exercise (urinary
nitrogen excretion)
• Primary role provides AA building blocks for
tissue synthesis
• Protein requirements for muscle tissue synthesis
with resistance training
FATS
*chemical composition
Saturate, Unsaturated, and Trans-fatty
*Role of fats?
LIPID FUNCTION
1. Energy (resting state
70%)
2. Transports - Fat-Soluble Vitamins
3. Insulation - subcutaneous fat
4. Protection - cushions vital organs
5. Structural component
6. Steroid hormones
7. Hunger depressor
Simple Lipids
G
L
Y
C
E
R
O
L
Fatty Acid
Fatty Acid
Fatty Acid
Trigylcerides
• Contain glycerol
(“backbone”) + 3 fatty
acids (“chains”)
• Most common form in
body (90-95% body
fats is in this form)
SIMPLE LIPIDS
Saturated Fats*
Unsaturated Fats
Solid at room temperature
Found in animal *products
*exception- coconut and palm oil,
veg., shortenings, and hydrogen
margarine
Liquid at room
temperature
Found in plant sources
PERCENTAGE OF SATURATED FAT IN
SOME COMMON FATS AND OILS
S
a
t
u
r
a
t
e
d
F
a
t
Coconut oil 86%
Palm kernel oil 81%
Butter 66%
Beef fat 48 %
Canola oil 6%
RECOMMENDED DIETARY
INTAKE FOR FAT
• 10% SF
30% of total
calories
10% MUSF
10% PUSF
Remember: 1 gram=9 kcals
9 grams of FAT x 9 kcals / gram = 81 kcal of FAT
“PHANTOM” FATS
Trans fats are unsaturated fats that have
picked up hydrogen atoms
and, as a result, now have a
structural shape similar to
that of saturated fats.
HYDROGENATION
• Low Density
Lipoproteins (LDLs)
• High Density
Lipoproteins (HDLs)
Depositor
Scavenger
Lipids are not water soluble and blood is 90% water.
Thus, lipoproteins are responsible for most lipid
transport in blood
> 35 mg/dl
< 130 mg/dl
Compound Lipids
DERIVED LIPIDS
Synthesized in the body
(endogenously - mostly LIVER)
Absolutely essential
for life!
Related to heart
disease!
Precursor for steroid
And several hormones,
required for
cell membranes!
DERIVED LIPIDS
Found only in animal products!
It does not contain FAs
(not considered a LIPID).
RDA: < 300 mg/day
Fiction Vs Fact
• What Promoters Claim
• What Research Support
High CHO diets are
fattening
When it comes to weight
control, CHOs are not
the problem.
What matters are calories
Calories eaten compared
to number or calories
burned.
Fiction Vs Fact
• What Promoters Claim
• What Research Supports
CHO-rich diets result in
increased insulin levels
in the body
The body’s ability to use
fat is influenced more by
the athletes activity level
than by insulin production
Too much insulin causes
the body to store CHOs
as fat.
Exercise is the way to burn
body fat.
Fiction Vs Fact
What Promoters Claim
What Research Support
“40-30-30” sports bars
enhance endurance by
Increasing fat burning
During exercise
These bars won’t improve
Endurance or fat
Metabolism
Too much insulin causes
The body to store CHOs
As fats
Faster fat metabolism
doesn’t come in a wrapper
Any more than bigger
muscles come in a can.