Nutrition & Metabolism

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Transcript Nutrition & Metabolism

Daily Caloric Intake

Carbohydrates: 45% – 65%

Fats: 20% -35%
 Mostly unsaturated
 Omega-3 fatty acids

Proteins: 10% - 35%

Actual amounts of each are dependent on
individual’s metabolism and activity
Carbohydrates

Most ingested as complex carbs
 Starches
 Cellulose

Refined carbs are unhealthy
 Vitamins, minerals & fiber removed
 Rapidly broken down into glucose
Absorption of Fats

Fatty acids and monoglycerides enter
epithelium of small intestine

Reassembled as triglycerides in
smooth ER
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Triglycerides, cholesterol, and
phospholipids are covered with protein
 chylomicrons
Absorption of fats, cont.

Chylomicrons enter lacteal of villi

Enters blood and transport fats to liver
and other tissues
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http://bcs.whfreeman.com/thelifewire/co
ntent/chp50/5002001.html
Processing of Fats

Lipoprotein lipase in blood breaks down
triglycerides:
 Fatty acids and glycerol can be taken up by
cells
 Cholesterol and protein taken up by liver

Liver repackages cholesterol and
triglycerides & binds with proteins
Cholesterol

HDLs
 Good cholesterol
 Collects excess and delivers to liver
 Decreases CVD

LDLs
 Bad cholesterol
 Delivers to cells
Types of Fats

Monounsaturated & stearic acid (sat fat in
chocolate)
 Raises HDL

Omega-3
 Lowers LDLs

Trans fats
 Raise LDL
 Lower HDL
Protein

In adults, there are 9 essential amino
acids

Complete proteins:
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Meat
Eggs
Fish
Nuts
Milk

Other protein sources may not have all the
essential amino acids or in proper proportion
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Gelatin
Soybeans
Beans
Peas
Peanuts
Healthiest sources of protein:
 Fish, chicken, nuts, legumes
Vitamins

Organic

Fat soluble vitamins – excess stored
 A: vision
 D: bone density, immunity, Ca absorption
 E: antioxidant
 K: clotting

Water soluble – excess excreted
 B
 C: immunity
NY Times article…
Minerals
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Inorganic
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Salts – Ca, K, Na, Cl, P, S, Mg, Cu, I, Fl,
Zn, Se
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Help with fluid balance

Most likely to be deficient in IRON
(anemia)
 Hemo- and myoglobin
 Cytochromes
Antioxidants

Oxidants/Free radicals
 Damage DNA
 Also damage cell membranes

Anitoxidants – destroy free radicals
 Selenium
 Magnesium
 Zinc
 Copper
 Many phytochemicals
 Tea
Phytochemicals

Plant compounds
 Fruits & veggies

Many are antioxidants
 Ex. Lycopene

Darker is better
Metabolism

BMR
 Metabolism under resting condition
 Amount of energy needed to carry on vital
life functions

TMR
 BMR + energy used in activity
Body Mass Index (BMI)

Relationship of height and weight
 Formula: weight (lb) / [height (in)]2 x 703

Used to determine obesity
 < 18.5 = underweight
 18.5 – 24.9 = normal
 25 – 29.9 = overweight
 > 30 = obese