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Chapter 8
Nutrition:
Eating for
Optimum Health
Lecture Outline
Copyright © 2010 Pearson Education, Inc.
written by Bridget Melton, Georgia Southern University
Objectives
• List the six classes of nutrients, and explain the
primary functions of each and their roles in
maintaining long-term health.
• Understand the factors that influence dietary
choices.
• Discuss how to change eating habits, improve
dietary behaviors, and use the USDA MyPyramid
Plan to make the best nutritional choices.
• Distinguish fact from fiction about trends in nutrition,
potential risks versus benefits of food supplements,
and the role of nutrition in fighting various diseases.
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Objectives (cont.)
• Discuss the nutritional concerns associated with life
events such as pregnancy, illness, or older age.
• Discuss the unique challenges that college students
face when trying to eat healthy foods and the actions
they can take to eat healthfully.
• Explain the food safety concerns that Americans
may face, as well as concerns in other regions of the
world.
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Assessing Eating Behaviors
• Hunger
• A lack of basic foods needed to provide the
energy and nutrients that support health
• Appetite
• A learned desire to eat that may or may not have
anything to do with feeling hungry
• Nutrition
• The science that investigates the relationship
between physiological function and the essential
elements of the foods we eat
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Activity Break: Why Do We Eat?
• In groups of four to five, list ten reasons why we eat.
• 5 minutes to complete
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Eating Influences
• Cultural and social
meanings attached
to food
• Convenience
• Emotional comfort
• Weight and body image
• Social interaction
• Habit or custom
• Regional and seasonal
trends
• Advertising
• Nutritional value
• Availability
• Environmental
conditions
• Economy
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Eating for Health
• Nutrients
• Energy yielding
• Proteins
• Fats
• Carbohydrates
• Vitamins
• Minerals
• Water
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Eating for Health (cont.)
A healthful diet is
• adequate, providing enough calories.
• one with moderate portion sizes.
• balanced, following the MyPyramid Plan.
• varied, achieved by eating a rainbow of foods.
• nutrient dense.
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Copyright © 2010 Pearson Education, Inc.
Obtaining Essential Nutrients
• Water
• Prevents dehydration
• Bathes cells
• Aids in fluid and electrolyte balance
• Transports molecules and cells
• Constitutes the major component of blood
• Proteins
• Carbohydrates
• Fats
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The Digestive Process
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The Digestive Process (cont.)
• Digestive process breaks down foods and causes
them to be either absorbed or excreted by the body.
• Saliva aids in chewing and swallowing as well as
containing enzymes.
• Esophagus is a tube that connects the mouth to the
stomach.
• Stomach is a digestive organ that allows food to mix
with enzymes and stomach acids.
• Small intestine allows nutrients to be absorbed into
the bloodstream.
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Proteins
• Function: growth and energy supply
• Types: break down into amino acids
• Complete proteins containing all nine essential
amino acids
• Animal products and a few plant products
• Incomplete proteins
• Grains, dry beans, nuts
• Guidelines
• Recommended intake is 0.8 gram per kilogram of
body weight.
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Copyright © 2010 Pearson Education, Inc.
Activity Break: Calculating Your Protein RDA
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Carbohydrates
• Function: primary energy source, especially in the
brain
• Types:
• Simple
• Natural sugars and added sugars; high glycemic index
• Complex
• Grains, cereals, veggies, beans; low glycemic index
• Athletic performance
• Carbohydrate loading
• Sugar and weight loss
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Complex Carbohydrates: Fiber
• Fiber is the indigestible portion of plant foods that
helps move foods through the digestive system.
• Insoluble fiber is found in bran, whole-grain breads
and cereal, and most fruits and vegetables.
• Soluble fiber comes from oat bran, dried beans, and
some fruits and vegetables.
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Fiber Benefits
• Protects against
• colon and rectal cancer.
• constipation.
• diverticulosis.
• breast cancer.
• heart disease.
• diabetes.
• obesity.
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Glycemic Index and Glycemic Load
Refined carbohydrates have few health benefits and
are a major factor in the growing epidemic of
obesity.
• Glycemic index rates the potential of foods to raise
blood glucose levels.
• Foods that break down quickly have a high glycemic
rating.
• Foods that digest slowly have a low glycemic rating.
• Glycemic load is the amount of carbohydrates in
food eaten multiplied by the glycemic index of that
food.
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Fats
• Fats (lipids) have a vital role in maintaining healthy
skin and hair, insulating body organs against shock,
maintaining body temperature, and promoting
healthy cell function.
• Triglycerides are the most common form of fat
circulating in the blood (95 percent of body fat).
The liver converts excess calories into triglycerides.
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Fats (cont.)
• Cholesterol constitutes some of the remaining 5
percent of body fat, and it can accumulate as plaque
on the inner walls of arteries, which is a major cause
of atherosclerosis.
• HDL
• LDL
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PUFAs and MUFAs
• Fat cells consist of chains of carbon and hydrogen
atoms.
• Saturated chains are unable to hold any more
hydrogen atoms.
• Monounsaturated fatty acids (MUFA)
• Polyunsaturated fatty acids (PUFA)
• Linoleic acid is an omega-6 fatty acid.
• Alpha-linolenic acid is an omega-3 fatty acid.
• Trans fat (partially hydrogenated)
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Trans Fatty Acids
• Trans fatty acids are produced when
polyunsaturated oils are hydrogenated to make
them more solid.
• Raise LDL and lower HDL
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Copyright © 2010 Pearson Education, Inc.
Vitamins
Functions
• Help put proteins, fats, and carbohydrates to use
• Essential to regulating growth, maintaining tissue, and
releasing energy from food
• Involved in the manufacture of blood cells, hormones, and
other compounds
Types
• Fat soluble: Vitamins A, D, E, and K
• Water soluble: B vitamins (eight total) and vitamin C
Goal
• Dietary reference intake
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Copyright © 2010 Pearson Education, Inc.
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Antioxidants
• Oxidative stress
• Free radicals
• Vitamins C and E, beta-carotene and other
carotenoids, and selenium
• Lycopene
• Lutein
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Folate
• Folate is the form of vitamin B believed to protect
against cardiovascular disease and decrease
homocysteine.
• Homocysteine is an amino acid that has been linked
to vascular diseases.
• Dietary folate equivalent (DFE) was established
to distinguish folate in food from its synthetic
counterpart folic acid.
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Minerals
Functions
• Help build bones and teeth
• Aid in muscle function
• Help our nervous system transmit messages
Types
• Fifteen minerals
• Macro: Sodium, potassium, chloride, calcium, phosphorus,
magnesium, and sulfur
• Trace: Iron, zinc, selenium, iodine, copper, manganese,
fluoride, and chromium
Goal
• Dietary reference intake
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Copyright © 2010 Pearson Education, Inc.
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Copyright © 2010 Pearson Education, Inc.
Copyright © 2010 Pearson Education, Inc.
Determining Your Nutritional Needs
• Recommended Dietary Allowances (RDAs)
• Adequate Intake (AI)
• Tolerable Upper Intake Level (UL)
• Daily Values (DVs)
• Dietary Reference Intakes (DRIs)
• Daily Reference Values (DRVs)
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Reading a Food Label
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Activity Break
In groups of three to five, answer the following
questions about your food product.
• How many servings does your item have?
• How many calories does your item have?
• What percentage of calories are from carbohydrates?
• What percentage is from simple sugars?
• Does it have vitamins or minerals?
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ABC News Video: You Are What You Eat
| You Are What You Eat
Discussion Questions
1. Is posting calorie counts on menus helpful? What other
dietary information would help people make the healthiest
choice?
2. Should more restaurants be required to follow this trend?
3. Is it up to a restaurant or a consumer to make people aware
of dietary information and healthy choices?
4. Are you surprised by some of the calorie counts?
5. Does seeing calorie counts affect your food choices?
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Making MyPyramid Work For You
www.mypyramid.gov
• Personalization
• Gradual improvement
• Physical activity
• Variety
• Moderation
• Proportionality
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The MyPyramid Plan
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Using the MyPyramid Plan
• Understanding serving sizes
• Serving: the recommended amount you should
consume
• Portion: the amount you choose to eat at any one
time
• Physical activity
• Choosing nutrient-dense foods
• Discretionary calories
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Portion Size
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Activity Break: 24-Hour Recall
• Take out a sheet of paper and write down everything
you have eaten in the past 24 hours.
• Write the food and the amount (cups and ounces)
next to it—your best guess.
• Tally your fruits, veggies, grains, meats, beans, milk,
and oils.
• Compare with the recommended amounts
(see next slide).
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Nutritional Needs for Different Groups
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Vegetarianism
• A vegetarian can
• completely avoid all animal food products.
• avoid only red meat.
• Benefits
• Better cholesterol levels
• Regular bowel movements
• Lower risk of heart disease
• Disadvantages
• Possible vitamin deficiencies
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Copyright © 2010 Pearson Education, Inc.
Improved Eating for the College Student
• Changing the “meat and potatoes” diet of Americans
• When time is short
• When funds are short
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Food Safety: A Growing Concern
• Foodborne illness
• Food irradiation
• Food additives
• Food allergy or food intolerance
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Common Foodborne Illnesses
• Campylobacter: the most common bacterial cause of
diarrhea illness in the world
• Salmonella: a bacterium commonly found in the
intestines of birds as well as reptiles and mammals
• E.coli 0157:H7: a bacterium that lives in cattle and can
contaminate water and food
• Caliciviruses: common cause of foodborne illness but
lab testing not widely available
• Listeria monocytogenes: a bacterium found in soil and
water that can contaminate raw foods such as
vegetables and meat
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Copyright © 2010 Pearson Education, Inc.
Food Additives
Additives are substances added to food to reduce the
risk of foodborne illness, prevent spoilage, and
enhance the way foods look and taste.
• Antimicrobial agents: salt, sugar, and nitrates that
make foods less hospitable for microbes
• Antioxidants: preservatives of color and flavor;
vitamins C and E are examples.
• Artificial colors, nutrient additives, and flavor
enhancers: fortifying agents such as folic acid and
flavorings such as MSG
• Sulfites: preserve vegetable color
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Irradiated Foods
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Food Allergy or Food Intolerance?
• Food allergy, or hypersensitivity: abnormal response
to a food triggered by the immune system
• Food intolerance: can cause symptoms of gastric
upset but is not the result of an immune system
response
• Lactose intolerance
• Monosodium glutamate (MSG)
• Some dyes
• Sulfites
• Gluten
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Organic Label
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Is Organic for You?
Organic foods and beverages are developed, grown,
or raised without the use of synthetic pesticides,
chemicals, or hormones.
• Organics of the twenty-first century are larger,
fresher looking, more affordable, and produced
according to USDA guidelines compared to those of
just a decade ago.
• Locavore is a term to describe people who eat only
food grown or produced locally.
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ABC News Video: Going Green
| Going Green
Discussion Questions
1. What can farmer’s markets do for a community?
2. Is it healthier to purchase from a farmer’s
market? Is there a difference in nutritional value?
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