Download Chapter 2 - Biol1322

The Pursuit of an
Ideal Diet
© 2007 Thomson - Wadsworth
Ask Yourself:
True or False?
1. It is wise to eat the same foods every day.
2. Milk is such a perfect food that it alone can provide all the
nutrients a person needs.
3. Cookies cannot be included in a healthful diet.
4. When it comes to nutrients, more is always better.
5. A person’s energy needs are based on his or her age, gender,
and physical activity levels.
© 2007 Thomson - Wadsworth
True or False?
6. From a nutritional standpoint, there is nothing
wrong with grazing on snacks all day, provided the
snacks meet nutrient needs without supplying too
many calories.
7. If you don’t meet your recommended intake for a
nutrient every day, you will end up with a
deficiency of it.
8. If a food label claims that a product is low-fat, you
can believe it is.
9. Most dietitians encourage people to think of their
diets in terms of the basic four food groups.
10. According to the government, people should try to
eat at least two cups of fruit and two and a half cups
of vegetables—totaling nine servings—a day.
© 2007 Thomson - Wadsworth
The ABCs of Eating for Health
 Adequacy: characterizes a diet that provides
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all of the essential nutrients, fiber, and energy
(calories) in amounts sufficient to maintain
health.
Balance: a feature of a diet that provides a
number of types of foods in balance with one
another, such that foods rich in one nutrient do
not crowd out of the diet foods that are rich in
another nutrient.
Calorie control: control of consumption of
energy (calories); a feature of a sound diet
plan.
Moderation: the attribute of a diet that
provides no unwanted constituent in excess.
Variety: a feature of a diet in which different
foods are used for the same purposes on
different occasions—the opposite of monotony.
© 2007 Thomson - Wadsworth
The ABCs of Eating for Health
 Nutrient dense: refers to a food that supplies
large amounts of nutrients relative to the number
of calories it contains.
 The higher the level of nutrients and the fewer the
number of calories, the more nutrient dense the
food is.
© 2007 Thomson - Wadsworth
The ABCs of Eating for Health
© 2007 Thomson - Wadsworth
Nutrient Recommendations
 Dietary Reference Intakes (DRI): a set of reference
values for energy and nutrients that can be used for
planning and assessing diets for healthy people.
 Established by a committee of nutrition experts selected by the
National Academy of Sciences (NAS)
 Based on latest scientific evidence regarding diet and health
 The first set was called the Recommended Dietary Allowances
(RDA); first published in 1941; revised ten times
 The series of DRI reports have been published since 1997
© 2007 Thomson - Wadsworth
The
DRI
Reports
Calcium, vitamin D, phosphorus, magnesium, and fluoride, 1997
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Folate, vitamin B12, other B vitamins, and choline, 1998
Vitamins C and E, selenium, and carotenoids, 2000
Vitamins A and K and trace minerals, 2002
Energy, macronutrients, and physical activity, 2002
Water, potassium, sodium, chloride and sulfate, 2004
Other food components (for instance, phytochemicals—the
nonnutrient compounds found in plant-derived foods like garlic
and soy)
 Alcohol
 DRI tables are located inside the cover of the textbook
 Full text reports are available at www.nap.edu
© 2007 Thomson - Wadsworth
Nutrient Recommendations
 Estimated Average
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Requirements (EAR)
Recommended Dietary
Allowances (RDA)
Adequate Intakes (AI),
Tolerable Upper Intake
Levels (UL)
Estimated Energy
Requirements (EER)
Acceptable Macronutrient
Distribution Ranges
(AMDR)
© 2007 Thomson - Wadsworth
Nutrient Recommendations
 Requirement: the minimum amount of a
nutrient that will prevent the development of
deficiency symptoms.
 Requirements differ from the RDA and AI, which
include a substantial margin of safety to cover the
requirements of different individuals.
© 2007 Thomson - Wadsworth
The Correct View of the DRI
© 2007 Thomson - Wadsworth
The Correct View of the DRI
© 2007 Thomson - Wadsworth
DRI Terms
 Estimated average requirement (EAR): the amount
of a nutrient that is estimated to meet the requirement
for the nutrient in half of the people of a specific age
and gender.
 The EAR is used in setting the RDA.
 Recommended dietary allowance (RDA): the
average daily amount of a nutrient that is sufficient to
meet the nutrient needs of nearly all (97–98%) healthy
individuals of a specific age and gender.
 Adequate intake (AI): the average amount of a
nutrient that appears to be adequate for individuals
when there is not sufficient scientific research to
calculate an RDA.
 The AI exceeds the EAR and possibly the RDA.
© 2007 Thomson - Wadsworth
DRI Terms
 Estimated energy requirement: (EER): the average
calorie intake that is predicted to maintain energy
balance in a healthy adult of a defined age, gender,
weight, height, and level of physical activity, consistent
with good health.
 Acceptable macronutrient distribution range
(AMDR): a range of intakes for a particular energy
source (carbohydrates, fat, protein) that is associated
with a reduced risk of chronic disease while providing
adequate intakes of essential nutrients.
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DRI Terms
 Tolerable upper intake level (UL): the maximum
amount of a nutrient that is unlikely to pose any risk of
adverse health effects to most healthy people.
 The UL is not intended to be a recommended level of
intake.
 The need for setting UL is the result of more and more people using
large doses of nutrient supplements and the increasing availability
of fortified foods.
 UL tables are located inside the cover of the textbook.
© 2007 Thomson - Wadsworth
Nutrient Recommendations
 Fortified foods: foods to which nutrients have been
added, either because they were not already present or
present in insignificant amounts.
 Examples: margarine with added vitamin A,
 milk with added vitamin D,
 certain brands of orange juice with added calcium,
 breakfast cereals with added nutrients and nonnutrients.
© 2007 Thomson - Wadsworth
Nutrient Recommendations
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
Other
Nutrition
Recommendations
Recommendations from the World Health
Organization (WHO)…
 Energy: Sufficient to support normal growth, physical activity, and
body weight (BMI 20–22).
 Total fat: 15 to 30% of total energy
 Saturated fatty acids: 0 to 10% of total energy
 Polyunsaturated fatty acids: 3 to 7% of total energy
 Dietary cholesterol: 0 to 300 milligrams per day
 Total carbohydrate: 55 to 70% of total energy
 Complex carbohydrates: 55 to 75% of total energy
 Dietary fiber: 27 to 40 grams per day
 Refined sugars: 0 to 10% of total energy
 Protein: 10 to 15% of total energy
 Salt: Upper limit of 6 grams per day
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
The Challenge of Dietary Guidelines
 People vary in the amount of a
given nutrient they need.
 The challenge of the DRI is to
determine the best amount to
recommend for everybody.
 Lifestyle diseases: conditions
that may be aggravated by
modern lifestyles that include
too little exercise, poor diets,
and excessive drinking and
smoking. Lifestyle diseases are
also referred to as diseases of
affluence.
© 2007 Thomson - Wadsworth
Dietary Guidelines for Americans 2005
 Adequate nutrients within energy needs
 Weight management
 Physical activity
 Food groups to encourage
 Fats
 Carbohydrates
 Sodium and potassium
 Alcoholic beverages
 Food safety
© 2007 Thomson - Wadsworth
Adequate Nutrients within Energy Needs
 Consume a variety of nutrient-dense foods and
beverages within and among the basic food groups
 Limit the intake of saturate & trans fats,
cholesterol, added sugars, salt, & alcohol
 Meet recommended intakes within energy needs
by adopting a balanced eating pattern, such as the
USDA MyPyramid Food Guidance System
© 2007 Thomson - Wadsworth
Weight Management
 To maintain body weight in a healthy range, balance
calories from foods and beverages with calories
expended
 To prevent gradual weight gain over time, make small
decreases in food and beverage calories and increase
physical activity
© 2007 Thomson - Wadsworth
Physical Activity
 Engage in regular physical activity and reduce
sedentary activities to promote health,
psychological well-being, and a healthy body
weight
 Achieve physical fitness by including
cardiovascular conditioning, stretching exercises
for flexibility, and resistance exercises or
calisthenics for muscle strength and endurance
© 2007 Thomson - Wadsworth
Physical Activity
 Specific recommendations:
 To reduce the risk of chronic disease in adulthood: 30
min of moderate-intensity physical activity on most days
 Greater health benefits: activity of more vigorous
intensity or longer duration
 To sustain weight loss in adulthood: 60-90 min of daily
moderate-intensity activity
© 2007 Thomson - Wadsworth
Food Groups to Encourage
 Consume a sufficient amount of fruits and
vegetables while staying within energy needs
 Choose a variety of fruits and vegetables each day
 Include selections from all 5 vegetable subgroups several
times a week
 Consume 3 or more ounce-equivalents of wholegrain products per day
 Consume 3 cups per day of fat-free or low-fat milk
or equivalent milk products
© 2007 Thomson - Wadsworth
 Consume less than 10% of calories from saturated fats
Fats
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Less than 300 mg of cholesterol per day
Keep trans fat consumption as low as possible
Keep total fat intake between 20% & 35% of calories
Choose from mostly polyunsaturated and
monounsaturated fat sources
 When selecting and preparing meat, poultry, dry beans,
and milk or milk products, make choices that are lean,
low fat, or fat free
 Limit intake of fats and oils high in saturated and/or
trans fatty acids, and choose products low in such fats
and oils
© 2007 Thomson - Wadsworth
Carbohydrates
 Choose fiber-rich fruits, vegetables, and whole grains
often
 Choose and prepare foods and beverages with little
added sugars
 Reduce the incidence of dental cavities by practicing
good oral hygiene and consuming sugar-and starchcontaining foods and beverages less frequently
© 2007 Thomson - Wadsworth
Sodium and Potassium
 Choose and prepare foods with little salt (less than
2,300 mg of sodium per day, or approx. 1 teaspoon of
salt)
 At the same time, consume potassium-rich foods, such
as fruits and vegetables
© 2007 Thomson - Wadsworth
Alcoholic Beverages
 Those who choose to drink should do so sensibly
and in moderation
 Moderation = 1 drink/day for women or 2 drinks/day for
men
 Some individuals should not consume alcoholic
beverages
 Should avoid alcoholic beverages when engaging
in activities that require attention, skill, or
coordination
© 2007 Thomson - Wadsworth
Food
Safety
 To avoid microbial foodborne illness:
 Clean hands, food contact surfaces, and fruits and
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vegetables
Meat and poultry should not be washed or rinsed
Separate raw, cooked, and ready-to-eat foods
Cook foods to a safe internal temp.
Chill perishable food promptly
Defrost foods properly
Avoid unpasteurized milk, milk products, and juices
Avoid raw or undercooked eggs, meat, poultry and
sprouts
© 2007 Thomson - Wadsworth
Tools Used in Diet Planning
 Food Group Plans separate foods into specific groups and then
specify the number of servings from each group to eat each day
 Serving - the standard amount of food used as a reference to give
advice regarding how much to eat
© 2007 Thomson - Wadsworth
 The MyPyramid Food
Guidance System calls for
eating a variety of foods to get
the nutrients you need and at
the same time the right
amount of calories to
maintain a healthy weight.
 Remember to balance the
energy consumed with the
energy expended in play.
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
MyPyramid
Design
 Make smart choices
from every food
group
 Find balance between
food and physical
activity
 Focuses on nutrientrich foods in sensible
portion sizes
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 Activity
 Moderation
MyPyramid
Key Components
 Regular physical activity
 Consume less of solid fats and
and reduced sedentary
activities
added sugars
 Consume more of nutrientrich foods
 Variety
 Eat foods from all
 Personalization
groups and subgroups
 One size does not fit all
 Proportionality
 Customize your plan at
www.MyPyramid.gov
 Identifies proportions of
foods that should make
a healthful diet
 Gradual improvement
 Take small steps to improve
diet and lifestyle everyday
 Visit www.smallstep.gov
© 2007 Thomson - Wadsworth
Using The Power
of the Pyramid
 Step 1: Estimate your
daily energy needs
 Step 2: Build your
daily eating plan
 Step 3: Let the
pyramid guide your
food choices
© 2007 Thomson - Wadsworth
Step 1: Estimating Daily Energy Needs
 Access www.MyPyramid.gov
 Enter age, gender and usual physical activity
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Step 2: Build Your Daily Eating Plan
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Step 3: Let the Pyramid Guide Your Food
Choices
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© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
Gaining Calorie Control
 Discretionary Calorie Allowance - the balance of
calories remaining in a person’s energy allowance after
accounting for the number of calories needed to meet
recommended nutrient intakes through consumption of
nutrient-dense foods in low-fat or no-added sugar forms
 Typically amounts to between 100 and 300 calories
 May be totally used by selecting foods higher in calories (example:
higher-fat meat, higher-fat dairy products, sweetened bakery
products)
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
 Calories assigned
can be
used to:
Discretionary
Calorie
Allowance
 Increase intake of basic food groups
 Select foods that are higher in fat or contain “added
sugar”
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“added sugar” includes sugar or caloric sweeteners added
during processing or preparation
 Add oils, “solid fats” or sugars to food or beverages
 “solid fats” include fats that are solid at room temperature
such as butter, lard or shortening
 Consume alcohol
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One fist clenched = 8 fl
oz
Two hands, cupped = 1
cup
Palm of hand
= 3 oz
One hand, cupped = ½
cup
Two thumbs together =
1 tbsp
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
Color Your Plate for Health
with a Variety of Fruits and
Vegetables
 Color your plate with health-protective foods
 At least 3 differently colored fruits/ vegetables per
day
 Be adventurous: select from as wide a variety of
fruits and vegetables as possible
 Make it easy on yourself!
© 2007 Thomson - Wadsworth
Food Labels
 Congress passed the Nutrition Labeling and Education Act
in 1990
 The Food and Drug Administration (FDA) enforces the law
for foods sold in the United States
 The law ensures that food companies provide nutrition
information in a standard format
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Food Labels
 By law, all labels must contain:
 Ingredients list: a listing of the ingredients in a food,
with items listed in descending order of predominance
by weight.
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All food labels are required to bear an ingredients list.
 Nutrition Facts panel: a detailed breakdown of the
nutritional content of a serving of a food that must
appear on virtually all packaged foods sold in the United
States.
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
Food Labels
 Fortified food: a food to
which manufacturers have
added 10% or more of the
Daily Value for a particular
nutrient.
 Daily Values: the amount of
fat, sodium, fiber, and other
nutrients health experts say
should make up a healthful
diet.
 The % Daily Values that
appear on food labels tell you
the percentage of a nutrient
that a serving of the food
contributes to a healthful diet.
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
Food Labels
 Nutrient content claims: claims such as
“low-fat” and “low-calorie” used on food
labels to help consumers who don’t want to
scrutinize the Nutrition Facts panel get an
idea of a food’s nutritional profile.
 These claims must adhere to specific
definitions set forth by the Food and Drug
Administration.
 Health claim: a statement on the food
label linking the nutritional profile of a
food to a reduced risk of a particular
disease, such as osteoporosis or cancer.
 Manufacturers must adhere to strict
government guidelines when making such
claims.
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
© 2007 Thomson - Wadsworth
Other Tools Used in Diet Planning
 Exchange lists: lists of categories
of foods with portion sizes
specified in a way that allows
foods to be mixed and matched or
exchanged for one another in the
diet
 Portion sizes are categorized
according to the calorie, protein
and fat content of the foods
 Useful for people who follow
calorie-controlled diets
© 2007 Thomson - Wadsworth
Other Tools Used in Diet Planning
 Food composition tables: tables that list the
exact number of calories, grams of fat, milligrams
of sodium and other nutrients commonly found in
foods
 Appendix E provides an extensive food composition
table
 Many versions of software are available containing food
composition databases that calculate and analyze diets
and recipes
© 2007 Thomson - Wadsworth
 American eating habits
have become as diverse as
the ethnic and cultural
groups that make up
America’s people
 Examine the ethnic and
regional pyramids to see
how they fit into a
healthful eating plan
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Mexican American Foods and MyPyramid
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A Chinese American MyPyramid Food Guide
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Mediterranean Food
Pyramid
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Fitting Indian Foods Into the MyPyramid
Food Guide
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Traditional African American Foods and
the MyPyramid Food Guide
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Fitting Jewish American Foods into the
MyPyramid Food Guide
© 2007 Thomson - Wadsworth