Transcript 3 supply energy

Nutrition Basics
Chapter 9
© 2008 McGraw-Hill Higher Education. All rights reserved.
Nutritional Requirements:
Components of A Healthy Diet
• 45 Essential nutrients
– Proteins, Fats, Carbohydrates, Vitamins,
Minerals and Water.
• Fuel Potential. Kilocalories (kcalorie).
• 1 Kcalorie = amount of heat it takes to raise the temperature
of 1 liter of fluid 1 degree of centigrade.
• 2000 kcalorie or calories per day meets a person needs.
• 3 supply energy
– Fat = 9 calories per gram
– Protein = 4 calories per gram
– Carbohydrates = 4 calories per gram
© 2008 McGraw-Hill Higher Education. All rights reserved.
Chapter 9
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Proteins
• Forms muscle, bone, blood, enzymes,
hormones and cell membrane.
– Twenty common amino acids
• Nine essential amino acids.
• Eleven nonessential amino acids
– Complete proteins provide all essential
amino acids (e.g., meat, fish, poultry, eggs, milk,
cheese, and soy).
• Most plant proteins are incomplete (e.g., peas,
beans, and nuts).
– Recommended amount
• 0.8 gram per kilogram of body weight (0.36g
per pound)
• 10-35% of total calorie intake
– Average is 15-16%
© 2008 McGraw-Hill Higher Education. All rights reserved.
Chapter 9
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Fats or Lipids
• Most concentrated source of energy
– stored energy and provides insulation and support
for body organs
– Two fats
• Linoleic acid (unsaturated fatty acid)
• Alpha-linoleic acid
– 10% from saturated fats
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– Triglycerides - glycerol molecule with 3 fatty acids
Saturated Fat (solid at room temperature)
Mono-unsaturated
Poly-unsaturated
Hydrogenation (H+ + unsaturated fat)
Trans fatty acids
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Chapter 9
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Fats and Health
• Cholesterol
*required for synthesis of cell membranes, vitamin D, and hormones
– High Density Lipo-Protein (HDLs) – good cholesterol; transport
cholesterol out of arteries
– Low Density Lipo-Protein (LDLs) – bad cholesterol; transport cholesterol
to organs and tissues, causing fat deposits on arterial walls
• Absorbs Fat-soluble vitamins (A,D,E & K)
– Make up 25%-35% of total daily calories
• 7% from saturated fat
• 10% from polyunsaturated fat
• 20% from monounsaturated fat
• Omega-3 fatty acids – AMDR -5-10%
• Omega-6 fatty acids – AMDR – 0.6-1.2%
• Recommended Intake
– Adults
• Men 17 grams per day of linoleic and 1.6 grams of alpha-linoleic
• Women 12 grams per day of linoleic and 1.1 grams of alpha-linoleic
– Only 3-4 teaspoons (15-20 grams) of vegetable oil per day
– AMDRs for total fat 20-35%
AMDR=Acceptable Macronutrient Distribution Ranges
© 2008 McGraw-Hill Higher Education. All rights reserved.
Chapter 9
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© 2008 McGraw-Hill Higher Education. All rights reserved.
Chapter 9
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Carbohydrates
• Supply energy for the body cells
• Two groups
– Simple Carbs: One or two sugar units
• Fruit, sugar, honey, malt (e.g., barley or wheat), and milk
– Complex Carbs: Multiple sugar units
• Starches and fiber
– Grains – wheat, rye, rice, oats, barley, and millet (white
grains)
– Legumes – dry beans, peas, and lentils
– Tubers – potatoes and yams
– Digestion
• Mouth and small intestines
• Break down to glucose
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Chapter 9
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Refined Carbohydrates Versus
Unrefined (Whole) Grains
• All grains before processing
– Inner layer, germ
– Middle layer, endosperm
– Outer layer, bran
• During processing
– Germ and bran are removed leaving
just the starch of the endosperm
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Chapter 9
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Glycemic Index and Glycemic
Response
• Insulin and glucose levels
• Quick rise in glucose and insulin
levels = high glycemic index
– Eating high glycemic index foods may
increase appetite
– May increase risk of diabetes and
heart disease
– Unrefined grains, fruits, vegetables
and legumes – relatively low glycemic
index
© 2008 McGraw-Hill Higher Education. All rights reserved.
Chapter 9
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Recommended Carbohydrate
Intake
• Average American – 200-300 grams
• 130 grams needed to meet the body’s
requirements for essential
carbohydrates
• Adults – 45-65% of total daily calories
or 225-325 grams
© 2008 McGraw-Hill Higher Education. All rights reserved.
Chapter 9
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Fiber – A Closer Look
• Food and Nutrition Board
– Dietary fiber nondigestible carbohydrate that is
present naturally
– Functional fiber nondigestible carbohydrate that has
been isolated or synthesized
– Total fiber is the sum of both
• Sources
– All plant substances
• Recommended intake
– 38 grams for adult men
– 25 grams for adult women
– Needs to come from foods not supplements
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Chapter 9
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Vitamins
• Organic (carbon-containing) substances
required in small amounts to promote specific
chemical reactions (catalyst) within a living
cell.
• Thirteen vitamins (see Table 9.1):
– Four Fat Soluble: A, D, E, and K.
– Nine Water Soluble: C and 8 B-complex vitamins. Thiamin
(B1), Riboflavin (B2), Niacin (B3), Pyridoxine (B6), Folate, B12, Biotin and Pantothenic acid.
• Sources:
– Human body does not manufacture most vitamins
– Abundant in fruits, vegetables and grains
© 2008 McGraw-Hill Higher Education. All rights reserved.
Chapter 9
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Minerals
• Inorganic compounds.
• Helps to regulate body functions, aid in
growth, maintenance of body tissues, and a
catalyst for energy release.
• 17 essential minerals (see Table 9.2).
– Major minerals - 100 milligrams or more.
• calcium, phosphorus, magnesium, sodium,
sulfur, sodium, potassium and chloride.
– Trace minerals – minute amounts.
• Cobalt, copper, fluoride, iodide, iron,
manganese, molybdenum, selenium,
and zinc
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Chapter 9
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Water
• Composed of about 50-60% water
• Can live up to 50 days without food , but only
a few days without water
• Water and other beverages make-up 80-90%
of your daily water intake
• Men – 3.7 total liters of water, with 3.0 liters
(13 cups) coming from beverages
• Women – 2.7 total liters of water, with 2.2 (9
cups) coming from beverages
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Chapter 9
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Other Substances in Food
Antioxidants –
– Reduction in cancers
– Vitamin C & E, selenium, carotenoids
• Phytochemicals
– Soy foods may help lower cholesterol levels
– Cruciferous vegetables render some
carcinogenic compounds harmless
– Allyl sulfides (garlic and onions) boosts the
cancer-fighting immune cells
© 2008 McGraw-Hill Higher Education. All rights reserved.
Chapter 9
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Basal Metabolic Rate
Your basal metabolic rate, or BMR, is the minimum calorific
requirement needed to sustain life in a resting individual. It can be
looked at as being the amount of energy (measured in calories)
expended by the body to remain in bed asleep all day!
BMR can be responsible for burning up to 70% of the total calories
expended, but this figure varies due to different factors (see below).
Calories are burned by bodily processes such as respiration, the
pumping of blood around the body and maintenance of body
temperature. Obviously the body will burn more calories on top of those
burned due to BMR.
© 2008 McGraw-Hill Higher Education. All rights reserved.
Harris-Benedict
Men: BMR = 66 + (13.7 X wt in kg) + (5 X ht in cm) - (6.8 X age)
Women: BMR = 655 + (9.6 X wt in kg) + (1.8 X ht in cm) - (4.7 X age)
Note: 1 inch = 2.54 cm.
1 kilogram = 2.2 lbs.
Example:
You are female
You are 30 yrs old
You are 5' 6 " tall (167.6 cm)
You weigh 120 lbs. (54.5 kilos)
Your BMR = 655 + 523 + 302 - 141 = 1339
calories/day
© 2008 McGraw-Hill Higher Education. All rights reserved.
Activity multiplier
Sedentary = BMR X 1.2 (little or no exercise, desk job)
Lightly active = BMR X 1.375 (light exercise/sports 1-3 days/wk)
Mod. active = BMR X 1.55 (moderate exercise/sports 3-5 days/wk)
Very active = BMR X 1.725 (hard exercise/sports 6-7 days/wk)
Extr. active = BMR X 1.9 (hard daily exercise/sports & physical job or 2X day
training, i.e marathon, contest etc.)
Example:
Your BMR is 1339 calories per day
Your activity level is moderately active (work out 3-4 times per week)
Your activity factor is 1.55
Your TDEE = 1.55 X 1339 = 2075 calories/day
Determine the energy cost: ______________________
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© 2008 McGraw-Hill Higher Education. All rights reserved.
USDA’s MyPyramid
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Chapter 9
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Vegetarians
• Possible reasons:
health
environmental concerns
financial considerations
ethics or religion
• Types:
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• A food plan for
vegetarians
Vegans (no animal products at all)
Lacto-vegetarians (milk and cheese)
Lacto-ovo-vegetarians (eggs and milk)
Partial vegetarians, semivegetarians,
and pescovegetarians (eggs, dairy
products, poultry and seafood)
© 2008 McGraw-Hill Higher Education. All rights reserved.
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Vitamin B-12
Vitamin D
Calcium
Iron
Zinc
Chapter 9
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© 2008 McGraw-Hill Higher Education. All rights reserved.
Chapter 9
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Protecting yourself Against
Foodborne Illness
• Causes of Foodborne Illnesses
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Campylobacter jejuni
Salmonella
Shigella
Escherichia coli
Listeria monocytogenes
Staphylococcus
Clostridium botulinum
Norovirus
• Preventing and treating foodborne illnesses
• Environmental Contaminants and organic foods
• Food Allergies
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Chapter 9
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Campylobacter jejuni
Escherichia coli
Salmonella
Staphylococcus
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Chapter 9
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Food Allergies and Food
Intolerances
• Food allergies
– Reaction of the body’s immune system
– Affect 2% of the adult population
– 4-6% of infants
– 90% of food allergies
• Cow’s milk, eggs, peanuts, tree nuts, soy,
wheat, fish, and shellfish
• Food intolerances (metabolic
problems)
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Chapter 9
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Connect Assignment
• Chapter 9 Connect Assignment Due Tuesday,
March 9th
• Extra Credit Assignment (10 pts.) Due
Wednesday, March 10th
•
Reminder: Quiz 2 (Chapters 7-9, next Wednesday, March 10th)
© 2008 McGraw-Hill Higher Education. All rights reserved.