Nutrition Final

  1. Carbohydrates
    6 Classes of Nutrients
  2. Carbohydrates, Fats, Protein
    • Organic
    • Contain Carbon
    • Has calories
  3. Vitamins
    • Organic
    • Contain Carbon
  4. Nutrients
    • Come from food
    • - Provide energy
    • - Provide building blocks
    • - Maintain body cells
  5. Essential
    Must be obtained from diet
  6. Vitamins, Water, & Minerals
    • Essential Nutrients
    • Don’t contain calories
  7. Energy-Yielding Nutrients
    • Energy measured in kCalories
    • - Carbohydrate
    • - Fat
    • - Protein
  8. Non Energy-Yielding Nutrients
    • Vitamins
    • Water
    • Minerals
  9. Vitamins
    • Organic compounds
    • Consumed in small quantities
    • Assist in body processes
    • Vulnerable to destruction
  10. Minerals
    • Inorganic elements
    • Consumed in varying quantities
    • Structural component- not metabolized, do not yield E
    • Indestructible
  11. Water
    • Indispensable and abundant
    • Often taken for granted
    • Enormous consumption compared to other nutrients
    • Participates in many chemical reactions
    • Provides environment for many body activities
  12. Carbohydrates and Protein
    Calorie value: 4
  13. Fat (lipid)
    Calorie value: 9
  14. Vitamins, Minerals, and Water
    Calorie value: 0
  15. Alcohol (not a nutrient)
    Calorie value: 7
  16. Calorie
    • A measurement of energy
    • Food is measured in kilocalories (kcal)
  17. Phyto-Chemicals
    • Some foods offer beneficial non-nutrients
    • Brightly colored pigments
  18. Anthropometric Data
    • Height, weight
    • Body Composition
  19. Body Composition
    • Skin fold
    • Underwater weighing
    • Bioelectrical impedance (low level current)
    • DEXA (low level x-ray)
  20. Biochemical (lab tests)
    Blood, urine
  21. Clinical
    • Physical exams
    • - Medical history
    • - Drug use, SES
  22. Dietary
    • 24 hour recall
    • Food record
    • Food frequency questionnaire
  23. Dietary Guidelines for Americans
    • Consume a variety of foods within and among basic food groups while staying within energy needs
    • Control calorie intake to manage body weight
    • Be physically active every day
    • Increase daily intake of fruits & vegetables, whole grains, & nonfat or low-fat milk and milk products
    • Choose and prepare foods with little salt
    • If you drink alcoholic beverages, do so in moderation
    • Keep foods safe to eat
  24. Healthy Diet
    To “ consume a variety of foods balanced by a moderate intake of each food”
  25. Nutrient Density
    Comparison of vitamin and mineral content to number of kcals
  26. Empty Calories
    Provides kcals and few to no other nutrients
  27. Energy Density
    Comparison of the kcal content to the weight of the food
  28. Dietary Reference Intake (DRI)
    • Nutrient standards for US and Canada
    • Nutrient recommendations to prevent chronic diseases
    • NOW considered malnutrition
  29. Dietary Reference Intake for Fiber
    • 38 grams for men (till age 50)
    • 25 grams for women (till age 50)
  30. Dietary Reference Intake Uses
    • Diet planning
    • Aim for RDA or AI
    • Do not exceed the upper limit
    • For the health population
  31. EAR: Estimated Average Requirement
    • Population-wide average nutrient requirements
    • Intake value to meet the requirement of 50% the healthy individuals in a particular life stage and of a given sex
  32. Estimated Average Requirement Uses
    Caloric needs (to prevent over-nutrition)

    • Females- 2000 calories a day
    • Males- 3000 calories a day
  33. RDA: Recommended Daily Allowance
    Vitamins and Minerals (to ensure adequate intake)
  34. UL: Tolerable Upper Level Intake
    • Highest level of usual daily nutrient intake likely to pose no risk of adverse health effects
    • Helps assess:
    • - Supplements
    • - Excess amounts of fortified foods
    • Not a goal, but a ceiling
    • Not enough information to set one for all nutrients
  35. AMDR: Acceptable Macronutrient Distribution Ranges
    • No RDA for Carbohydrate, Protein or Fat, but…
    • Ranges of intakes are recommended that are associated with reduced risk of chronic disease
    • - Carbohydrates: 45-65% total energy
    • - Protein: 10-35% total energy
    • - Fat 20-35% total energy
  36. My Pyramid
    • 6 food groups represented by colors
    • Choose food in approximate proportion to the base widths of the bands
    • Physical activity
    • Moderation
    • Not for children under age 2
    • Each food is deficient in at least one essential nutrient
    • Variety is key
    • Calorie and nutrient content may vary within a food group
  37. 6 oz every day
    1 slice of bread= 1 oz
    Grains (My Pyramid)
  38. 2 ½ cups every day
    Vegetables (My Pyramid)
  39. 2 cups every day
    Fruits (My Pyramid)
  40. 3 cups every day
    For children 2-8: 2 cups
    Milk (My Pyramid)
  41. 5 ½ oz every day
    Piece of meat= deck of cards= 3 oz
    Meat and Beans (My Pyramid)
  42. Diet Planning with the Exchange System
    • 7 Major food groups
    • Foods are grouped according to calories (energy), carbohydrate, and fat content
    • Portion Size
    • Foods may be grouped in an “unlikely” place
    • - Bacon, peanuts, avocados are in the fat group
    • - Cheese is a “high fat” meat
  43. Starch/Bread
    Milk (nonfat, low fat, whole)
    Other Carbohydrates
    Meat (very lean, lean, medium fat, high fat)
    7 Major Food Groups of Exchange System
  44. Food and the Body
    • Taking food into the mouth DOES NOT assure admission to the body
    • When food is in G.I. tract, it is OUTSIDE the body
  45. General Functions of a GI System
    • Propulsion and mixing of GI contents
    • Secretion of Digestive Juices
    • Digestion of food
    • Absorption of nutrients
  46. Digestion
    The process by which food is broken down into absorbable units
  47. Mouth
    Digestion begins here (especially carbohydrate digestion)
  48. Salivary Glands
    • Enzymes:
    • - Salivary amylase: For carbohydrates
    • - Lingual lipase: For fats
  49. Esophagus
    “tube” from mouth to stomach
  50. Stomach
    • Holds food for 2-4 hours, capacity is 4 cups
    • Grinds and churns swallowed food, mixing it with acid and enzymes= “chyme”
    • Stores food: if you don't have one (e.g. surgery), must eat small frequent meals
    • Acid medium kills bacteria and helps absorption of iron, calcium
    • Secretes an ‘Intrinsic Factor’ need for vitamin B12 absorption
    • Mucus layer prevents autodigestion
    • Strongest muscle in intestinal tract
  51. Small Intestine
    • Major site of digestion and absorption
    • About 10 feet long
    • Divided into: Duodenum, jejunum, ileum
    • Once here, chyme inhibits motor activity of stomach
  52. Emptying into Small Intestine Depends On..
    • Fluidity of chyme
    • Amount of chyme in the small intestine
    • Amount of fat present (slows emptying)
  53. Large Intestine (Colon)
    • Lower part of intestine
    • Completes digestion
    • Absorbs water and minerals
    • Divided into: ascending colon, transverse colon, descending colon, sigmoid colon
    • Removes water (chemical aspect)
  54. Appendix
    Narrow blind sac at the beginning of the colon role in immune system: stores lymph cells
  55. Pancreas
    Gland that secretes digestive enzymes and juices into small intestine
  56. Liver
    Produces bile
  57. Gall Bladder
    Stores bile and secretes bile into small intestine
  58. Peristalsis
    Waves of contractions involving circular and longitudinal muscles throughout GI tract
  59. Stomach Action
    Strongest muscles of GI, turn food into “chyme” (mixture of food and GI juices, very acidic)
  60. Sphincters
    Circular muscles at specific points in GI tract that act as gates to regulate flow
  61. Saliva
    Contains enzymes; especially for carbohydrate digestion
  62. Gastric Juice
    • From stomach, made of enzymes and hydrochloric acid (HCl)
    • Especially used for protein digestion
    • Mucus protects stomach from HCl
  63. Pancreatic Juice (Secreted into Intestine)
    • Enzymes for carbohydrates, protein, fat
    • Bicarbonate to neutralize “chyme” coming from stomach
    • Intestinal enzymes:
    • - Enzymes for carbohydrates, protein, fat
    • - Enzymes work best in neutral pH
  64. Bile
    • Made by the liver, stored in the gall bladder
    • Gall bladder squirts it in to Small Intestine when fat is present
    • Not an enzyme, but an emulsifier (break fat into little droplets)
  65. Protective Factors
    • Good bacteria + intestinal flora
    • Probiotics
  66. Good bacteria + Intestinal Flora
    • Make some vitamins
    • Protect against “bad” bacteria, viruses
  67. Probiotics
    Supplements containing “good bacteria”
  68. Big Unit -> Little Unit
    • Protein -> amino acids*
    • Carbohydrates -> monosaccharide*
    • Fat -> fatty acids* and glycerol*
    • *These cross the intestinal cell into the bloodstream
    • - They are absorbed
  69. Anatomy of the Absorptive System
    • Surface of small intestine covered with “villi"
    • Villi (and microvilli) increase surface area that of a tennis court!
  70. Villi
    Finger-like projections
  71. Intestinal Cells
    • Villi and microvilli contain enzymes and “pumps”
    • Specialized: Different nutrients are absorbed in different areas of the small intestine
    • Contains a blood supply and lymph
    • Nutrient transport
  72. Nutrient Transport of Intestinal Cells
    Goes to bloodstream or lymphatic system
  73. Bloodstream
    • Water soluble nutrients -> go here
    • Monosaccharide’s, amino acids, small fats, minerals, water soluble vitamins (= B vitamins and Vitamin C)
    • Go first to liver via portal vein
    • Liver is the major metabolic organ of the body
  74. Lymphatic System
    • Fat soluble nutrients -> go here
    • Larger fats and fat-soluble vitamins (Vitamin A, E, D, K)
    • Does not go to liver first, but empties into blood near heart
    • Lymph is similar to blood, but no red cells or ‘pump’
    • Lymph squeezed by muscles to circulate in contents
  75. Simple Diffusion
    Water and small lipids
  76. Facilitated Diffusion
    Water-soluble vitamins (B & C)
  77. Active Transport
    Glucose and Amino acids
  78. Myth of "Food Combining"
    • It is a myth that can’t eat certain food combinations
    • Food can help each other be absorbed
    • Example: Vitamin C helps iron absorption
  79. Large Intestine Digestion
    • Nutrient digestion already complete
    • Some digestion of fiber by bacteria
    • Fiber has NO calories
  80. Large Intestine Absorption
    • Water
    • Sodium, potassium, chloride
    • Vitamin K (produced by bacteria)
  81. Large Intestine Elimination
    Get rid of what we don’t use
  82. Gastro-Esophageal Reflux Disease
    • Stomach contents re-enter esophagus
    • Treatment:
    • - Small meals
    • - No food 3 hours before bed
    • - Elevate head of bed
    • - Use antacids
    • Choking
  83. Celiac Disease
    • Gluten-sensitive enteropathy
    • Allergic to gluten
    • - Antibodies attack microvilli -> GI inflammation
    • Managed by gluten-free diet
    • - No wheat, rye, barley
  84. Irritable Bowel Syndrome
    • Affects 20% of Americans
    • Cramps, gassiness, bloating, irregular bowel function
    • Treatment
    • - Elimination diet: Meat and Starches
    • - Moderate caffeine
    • - Low fat, small meals
    • - Stress reduction
  85. What's on a Food Label
    • Product name
    • Company’s name and address
    • Ingredients in descending order by weight
    • Amount in the product
    • Product bar code
    • *Nutrition facts panel*
  86. The Daily Values
    • Daily goals of a person consuming 2000 kilocalories
    • Helps consumers tell whether or not a food has a lot or little of a nutrient
    • Makes it easier to compare brands
  87. Descriptive Terms for Food Labeling
    • If less than 2 milligrams of cholesterol and 2 milligrams or less of saturated fat, then can say “cholesterol free”
    • If raw and never been frozen, can say “fresh”
    • Health claims
    • - FDA approves statement linking diet and health
    • - The nutrient or food substance must be related to a disease or health condition for which most people or a specific group of people, such as the elderly, are at risk
  88. Carbohydrates
    • Populations of the world derive more than ½ of their nutrients from these types of foods
    • Easy to grow
    • Highly palatable
    • Can be stored for reasonable periods
    • Classic examples: rice, corn, wheat, potatoes, oats
  89. Simple Carbohydrates (sugars)
    Complex Carbohydrates (starches and fiber)
    2 Main Carbohydrates in Food
  90. Simple Carbohydrates
    • Monosaccharides
    • Disaccharides
  91. Monosaccharides
    • Glucose
    • Fructose
    • Galactose
  92. Glucose
    • Found in fruits, vegetables, honey
    • “Blood sugar” – used for energy, essential
  93. Fructose
    • “Fruit sugar”
    • Found in fruits, honey, corn syrup
  94. Galactose
    Found as part of lactose in milk
  95. Complex Carbohydrates
  96. Polysaccharides
    • Starch
    • Glycogen
    • Dietary Fiber
  97. Starch
    • Long chains of glucose units
    • Amylose
    • Amylopectin
  98. Amylose
    Straight chains
  99. Amylopectin
    Branched chains
  100. Glycogen
    • Body makes this
    • Highly branched chains of glucose units
    • Body’s storage form of carbohydrate in muscles and liver
  101. Dietary Fiber
    • Can’t digest (get 0 calories from this – if you can’t digest a food, the food doesn’t get into your blood stream, therefore you don’t gain calories)
    • Chains of monosaccharides
    • - Short chains
    • - Long chains
  102. Soluble Fiber
    • Found in oats, legumes (dried peas and beans)
    • Lowers blood cholesterol
  103. Insoluble Fiber
    • Found in grains, vegetables
    • Increases GI transit (moves food through GI faster)
    • - Prevents constipation
  104. Carbohydrate Digestion
    • End products of this digestion:
    • Monosaccharides: glucose, fructose, galactose
    • - Absorbed into bloodstream
    • Fibers are not digested (zero calories), excreted in feces
  105. Carbohydrate Intake
    • 45-65% of kilocalories
    • Daily value (for 2,000 kcal) = 300 grams
    • Dietary guidelines
    • - Moderate sugar intake
    • - Variety of grains, fruits, and vegetables
  106. High Sugar Intake
    • Low nutrient content
    • Contributes to tooth decay
    • If excess kcal, contributes to obesity
  107. High Fiber Intake
    • Better control of blood glucose
    • Reduced risk of heart disease
    • Healthier GI functioning
  108. Sugar
    • As an additive, this may...
    • Enhance flavor
    • Provide fuel for fermentation (bread, beer, wine)
    • Act as a preservative (jams)
    • Balances acidity of tomato and vinegar-based products
  109. Lactase
    enzyme that digests disaccharide lactose
  110. Lactose Intolerance
    • Symptoms: bloating, gas, diarrhea
    • Causes: lactase deficiency or decreased lactase activity, or damage of intestinal villi by disease
    • Prevalence

    Only 30% of adults worldwide can digest lactose thru out their lifespan
  111. Dietary Changes for Lactose Intolerance
    • Low lactose dairy products, e.g. aged cheese and yogurt are ok
    • Must limit milk, ice cream
    • Can use Lactaid milk, lactase pills
    • Other calcium sources: Ca-fortified orange juice, soymilk, canned sardines or salmon with bones
  112. Glycemic Index
    • Classifies foods based on their potential to raise blood glucose levels
    • Expressed as a percentage of the response of glucose (glucose = 100%)
    • High glycemic index foods trigger sharp rise in blood glucose
  113. Glycemic Index is Infected by:
    • Type of carbohydrate
    • Cooking process
    • Presence of fat or fiber
  114. Triglycerides
    1 glycerol + 3 fatty acids
  115. Saturated Fats
    • No double bonds
    • Solid at room temperature
    • Usually of animal origin
    • Food sources: butter, lard
    • Exceptions: Coconut oil, palm oil
    • - From plants
  116. Monounsaturated Fats
    • One double bond
    • Liquid at room temperature, but will become solid if refrigerated
    • Food sources: olive oil, canola oil, peanut oil, sesame oil
  117. Polyunsaturated Fats
    • 2 or more double bonds
    • Liquid at room temperature or refrigerator temperature
    • Usually of plant origin
    • Food source: corn oil, safflower oil
    • Omega-3
    • Omega-6
  118. Omega-6
    • Found in vegetable oils and meats
    • Serve as raw material for the production of eicosanoids in the body
    • EFA deficiency symptoms
    • - Growth retardation, reproductive failure, nerve problems
    • - Uncommon, but if have chronic disease, may become deficient
    • - Most common form of fat in food and in body
  119. Phospholipids
    • Similar to Triglyceride
    • Contains phosphate and nitrogen
    • Lecithin (not an essential nutrient)
  120. Function of Phospholipids
    • Constituent of cell membranes
    • Emulsifying agent- helps fat and water mix- also used in food industry
    • Contain nitrogen and phosphorous
  121. Sterols
    Composed of multiple ring structures
  122. Function of Sterols
    • They are the starting material for:
    • Cholesterol (endogenous)
    • Bile acids
    • Sex hormones (estrogen, testosterone)
    • Adrenal hormones (cortisol)
    • Vitamin D
    • Cholesterol can be converted to all of the above
  123. Dietary Source of Sterols
    • Cholesterol is one that is found in foods of ANIMAL ORIGIN
    • Only meat, eggs, dairy, shellfish, fish
    • Eggs and shrimp have highest cholesterol

    Maximum intake a day is 300 mg
  124. Lipid Digestion
    • Most of the digestion takes place in the Small Intestine
    • First must be “emulsified” by bile
  125. Facts about Bile
    • Made from cholesterol
    • Can either be reabsorbed and reused OR
    • Can be trapped by soluble fiber (oats) in the intestine and then excreted
    • If excreted, then more cholesterol must be used to make more bile
    • Liver uses blood cholesterol to make this
    • Nothing is stored in the liver
    • Stored in gall bladder
  126. Absorption and Transportation of Lipids
    • Small fats (water soluble) -> blood -> liver
    • Larger fats (non-water soluble) -> packaged into chylomicrons -> lymph system -> blood
    • Chylomicrons contain TG, cholesterol, phospholipids
  127. Lipid Transport through the Blood
    They are transported as Lipoproteins (transport vehicle= clusters of lipids with protein around it)
  128. Types of Lipoproteins in Blood
    • Chylomicrons
    • Very Low Density Lipoproteins (VLDL)
    • Low Density Lipoproteins (LDL)
    • High Density Lipoproteins (HDL)
  129. Low Density Lipoproteins
    • “Bad Cholesterol"
    • LDL gives up cholesterol to cells
    • Less healthy
  130. High Density Lipoproteins
    • “Good cholesterol”
    • Transports cholesterol back to liver from the cells (body tissues) for disposal
    • Healthy
  131. Cardiovascular Disease
    • Elevated (total) blood cholesterol is major risk factor
    • Dietary saturated fatty acids raise blood cholesterol more than dietary cholesterol does
    • Raises LDL and lowers HDL
    • Some research suggests..
    • - Polyunsaturated fats lower LDL
    • - Monounsaturated fats raise HDL
  132. Omega-3 Fatty Acids
    • Diets high in fish oils
    • Lowers blood cholesterol and reduces risk of Cardiovascular Disease
    • It is recommended that fish be consumed at least once/week
  133. To Improve LDL/HDL Ratio
    • Weight control
    • Mono- and Polyunsaturated fats in diet
    • Soluble fibers (oat bran)
    • Antioxidants (vitamin C, vitamin E)
    • Moderate alcohol consumption
    • Exercise
    • Being female
  134. Cancer and Lipids
    High dietary fat (saturated fat) may increase in some cancers (breast, prostate)
  135. Obesity and Lipids
    Dietary fat is easily converted (90% efficient) to body fat
  136. Hydrogenation
    • Hydrogen gas is mixed with a liquid fat (oil)
    • Causes fatty acids to be more saturated and thus more solid
    • Hydrogenated corn oil- margarine
    • Also causes formation of trans fats
  137. Trans-Fatty Acids
    • Can form during hydrogenation
    • Very common in:
    • - Margarine
    • - Baked products
    • - Snack chips/crackers
    • Are unhealthy because they may increase heart disease
    • Very difficult for the body to metabolize, so they can build up in the body
  138. Olestra Pros
    • No cholesterol
    • 0 calories
    • Body does not recognize it as a fat
  139. Olestra Cons
    • Upset stomach
    • Won’t be broken down in liver
    • Loss of vitamins
  140. Fats in Diet
    • Added Fats
    • Meat, poultry, fish, eggs, and nuts
    • Milk, yogurt, cheese
  141. Recommended Intakes of Fat
    • Reduce total fat intake
    • - 20-5% of less of kilocalorie; but don’t go less than 15% of kilocalorie
    • Reduce saturated fat intake
    • - <10% of kilocalories
    • Reduce cholesterol intake
    • <300 mg/day
    • Select lean meats and nonfat milks
    • Eat plenty of vegetables, fruits, and grains
    • Use fats and oils sparingly
Card Set
Nutrition Final