How Nutrients Become You
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Six Nutrient Groups
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Carbohydrates
Fats
Proteins
Vitamins
Minerals
Water
Chemistry of Nutrition
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Elements-simplest substances
Matter-takes up space; is measurable
Molecule
smallest amount of substance with characteristics
of the substance
– made of two or more atoms bonded together
COMPOUND is formed when atoms of different
elements are bonded together
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Functions of Nutrients
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Build and repair body tissues
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Regulate body processes
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Growth spurts, injuries, illness
Circulation, digestion, absorption, metabolism
Provide energy
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Fuel
Carbs and fats
Energy Value of Food
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Kilocalorie-amount of heat required to raise
one kilogram of water one degree Celsius
Kilocalorie=Calories
Fats=9 calories/gm
Carbohydrates=4 calories/gm
Protein=4 calories/gm
Alcohol=7 calories/gm (no nutrient value!)
The Process of Digestion
Body breaks down food into simpler
substances
 Mechanical Digestion-chewing…
 Chemical Digestion
– Enzymes (protein) cause chemical
reactions
 GI Tract-25-30’ (mouth to anus)
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5-14 hours from mouth to sm. intestine
Components of GI tract
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Mouth-mastication, saliva
Esophagus (10 “)
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parallels trachea (epiglottis)
Peristalsis-moves food through
Stomach (3 hours-fats take longest)
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Gastric juices: HCl, enzymes, mucous
Chyme
Pepsin begins protein breakdown
GI con’d
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Small Intestine (95% digestion occurs here)
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20’ long when stretched…1” diameter
Duodenum(12”)
Jejunum (4 ‘)
Ileum (5 ‘)
Large Intestine (colon)
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Little digestion
Water reabsorption
Bacteria work on fiber
Feces pass through rectum and anus
Absorption of Nutrients
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Passage of nutrients from digestive to
circulatory and lymphatic systems
Water soluble nutrients
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Amino acids, monosaccharides, minerals, vitamin
C, B vitamins
Fat soluble nutrients
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Vitamins A, D, E, K, fatty acids, glycerol,
monoglycerides
Metabolism
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Chemical changes producing energy
Energy stored in muscles-adenosine
triphosphate (ATP)
Waste products from cell metabolism
discarded through
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Kidneys
Lungs
Skin
Factors Affecting Digestion
 Eating
habits
 Emotions
 Food allergies
 Physical exercise
Digestive Disorders
Diarrhea
 Constipation
 Indigestion
 Heartburn (GERD)
 Ulcer
 Gallstones
 Diverticulosis
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