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Chapter 3
NUTRITION FOR WELLNESS
Objectives
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Define nutrition and describe its relationship to health and wellbeing.
Learn to use the USDA MyPlate guidelines for healthier eating.
Describe the functions of the nutrients – carbohydrates, fiber, fats,
proteins, vitamins, minerals, and water – in the human body.
Define the various energy production mechanisms of the human
body.
Be able to conduct a comprehensive nutrient analysis and
implement changes to meet the Dietary Reference Intakes (DRIs).
Identify myths and fallacies regarding nutrition.
Become aware of guidelines for nutrient supplementation.
Learn the 2010 Dietary Guidelines for Americans.
Eat this or that?
Introduction
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Proper nutrition is essential to overall health
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Having good nutrition:
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Means that a person's diet supplies the essential
nutrients needed to carry out normal tissue growth and
repair.
Supplies enough substrates to fuel all body processes.
The USDA provides nutrition guidelines and
recommended daily food amounts according to
various caloric requirements.
Introduction
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Nutrients should be obtained from a wide variety of
sources.
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U.S. diet
Too high in calories, sugar, saturated fat, trans fat,
sodium
 Too low in grains, fruits, vegetables
 Diet and nutrition play a role in the development and
progression of heart disease, cancer, obesity, diabetes,
and osteoporosis
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Nutrients
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Six essential nutrients
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By function:
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Fuel Nutrients needed for energy: carbohydrates, fats,
and proteins.
Regulatory nutrients necessary to function normally
with no caloric value: vitamins, minerals, water, and
fiber.
By Amount:
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Macronutrients needed in proportionally large amounts
daily: carbohydrates, fats, proteins, and water.
Micronutrients required in small amounts daily:
vitamins and minerals.
Nutrients
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Nutrient Density
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Foods packed with nutrients but with low or moderate
calories are classified as having high nutrient density.
Calorie:
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The simplified term for a kilocalorie (kcal), the amount
of heat necessary to raise the temperature of 1
kilogram of water 1 degree Centigrade.
MyPlate food plan
MyPlate food groups
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Vegetables are divided into 5 subgroups
Dark green vegetables
2.
Red and orange vegetables
3.
Beans and peas
4.
Starchy vegetables
5.
Other vegetables
Fruits
Grains are divided into 2 subgroups
Whole grains
Refined grains
1.
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Protein
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Includes meat, poultry, seafood, beans and peas, eggs, soy
products, nuts and seeds
Dairy
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Choose low-fat or fat-free options
Cream cheese, cream and butter are not part of the dairy group
Recommended daily amounts of nutrients
Carbohydrates
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Major source of energy (4 calories/gram)
Regulate fat and metabolize protein
Major sources are breads, cereals, fruits,
vegetables, milk/dairy products
Two types:
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Simple
Complex
Major Types of Carbohydrates
Simple Carbohydrates
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Often called “sugars,” which have little nutritive value
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Examples are candy, soda, and cakes
Divided into monosaccharides and disaccharides
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Monosaccharides: glucose, fructose, galactose
Disaccharides: sucrose, lactose, maltose
Complex Carbohydrates
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Also referred to as “polysaccharides”
Carbohydrates formed by ten or more
monosaccharide molecules linked together
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Starches
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Dextrins
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Storage form of glucose in plants
Formed from the breakdown of starches exposed to dry
heat
Glycogen
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Storage form of glucose
Fiber
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Form of complex carbohydrates
Present mainly in plant leaves, skins, roots, and seeds
Processing and refining foods removes most of their
natural fiber
Dietary sources include
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Whole-grain cereals and breads
Fruits and vegetables
Legumes
Fiber
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Soluble fiber
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Insoluble fiber
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Dissolves in water to form gel-like substance that encloses food particles
Helps decrease blood cholesterol and blood sugar levels
Oats, fruits, barley, legumes, psyllium
Not easily dissolved in water but binds with water
Causes a softer and bulkier stool
Speeds passage of food residues through intestines
Wheat, cereals, vegetables, skins of fruits
Most common types of fiber are:
1.
2.
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4.
Cellulose – found in plant cell walls
Hemicellulose – found in cereal fibers
Pectins – found in vegetables and fruits
Gums and mucilages – found in small amount of food of plant origin
High-fiber foods are essential in a healthy diet
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Age 50 and under
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Over age 50
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Women = 25 g/day
Men = 38 g/day
Women = 21 g/day
Men = 30 g/day
Current average daily U.S.
intake
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About 15 g/day
Fat
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Also called lipids
Most concentrated source of energy (9 cal/gram)
Need fat for:
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Part of cell structure
Stored energy
Insulator for body heat preservation
Shock absorption
Supplies essential fatty acids
Carries fat-soluble vitamins (A, D, E, K)
Major types of fats (lipids)
Simple Fats
Over 90% of the weight of
fat in foods and over 95% of
the fat stored in the body
are in the form of
triglycerides
Saturated fats are mainly of
animal origin
Unsaturated are found
mostly in plant products
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Further classified into
monounsaturated and
polyunsaturated fatty acids
Chemical structure of saturated and unsaturated fats
Saturated Fats
Meats, animal fat, lard,
whole milk, cream, butter,
cheese, ice cream,
hydrogenated oils, coconut
oil, and palm oils
Usually do not melt at room
temperature
Coconut oil and palm oils
are exceptions
Raise blood cholesterol
level
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Unsaturated Fats
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Usually liquid at room temperature
Help lower blood cholesterol
Monounsaturated fats (MUFAS)
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found in olive, canola, peanut, sesame oils, avocados,
cashews, and peanuts
Polyunsaturated fats (PUFAS)
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found in corn, cottonseed, safflower, walnut,
sunflower, soybean oils, and fish, almonds, pecans
Fats (Lipids)
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Trans fatty acids
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The result of partial hydrogenation to increase shelf life.
Provide no known health benefit.
The words "partially hydrogenated" and "trans fatty
acids" indicate that the product carries a health risk just
as high as or higher than that of saturated fat.
Found in
 Margarine and spreads, shortening, some nut
butters, crackers, cookies, dairy products, meats,
processed foods, and fast foods
Fats (Lipids)
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Polyunsaturated omega fatty acids
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Essential to human health and have to be consumed in the
diet.
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Omega-3 fatty acids
Polyunsaturated fatty acids found primarily in cold-water
seafood and flaxseeds thought to lower blood cholesterol
and triglycerides
Three major types of omega-3 fatty acids:
EPA, DHA, and ALA
protect against irregular heartbeats and blood clots,
reduce triglycerides and blood pressure, and defend
against inflammation.
Omega-6 fatty acids
LA, GLA, and AA
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Excessive intake tends to contribute to inflammation
– 4 to 1 ratio recommended
Fats (Lipids)
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The canning process for
fish destroys most of
the omega-3 fatty acids
Good sources of
omega-3 ALA include
flaxseeds, canola oil,
walnuts, wheat germ,
and green leafy
vegetables
Fats (Lipids)
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Compound fats
 Lipoproteins transport fats in the blood and
play a large role in heart disease
 Major forms are HDL, LDL, VLDL
Derived fats
 Sterols
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Found in food and manufactured in the body
primarily from saturated and trans fats
Proteins
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Needed for:
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Build and repair tissue
Part of hormones, antibodies, and enzymes
Necessary for normal functioning
Help maintain normal body fluid balance
Source of energy (4 calories/gram) if carbohydrate is
insufficient
Sources are meats and alternatives, milk, and other dairy
products
Excess proteins can be converted to glucose or fat, or
excreted in urine
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Daily consumption of beef, poultry, or fish should be limited to 3
ounces to 6 ounces.
Amino Acids
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The body uses 20 amino acids
to form different types of
protein
9 amino acids are termed
“essential” because the body
cannot produce them
11 amino acids are termed
“nonessential” because the
body can produce them if
food proteins in the diet
provide adequate nitrogen
All amino acids must be
present in the diet for the
body to function normally
Vitamins
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Organic nutrients essential for normal metabolism,
growth, and development
Classified according to solubility
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Fat soluble (A, D, E, and K)
Water soluble (B complex and C)
Most vitamins must be obtained through diet
A, D, and K are formed in the body
C, E, and beta-carotene are “antioxidants”
Minerals
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Inorganic nutrients essential for normal body
functions
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Part of all cells
Help maintain water balance and acid-base balance
Essential components of enzymes
Regulate muscular and nervous tissue impulses, blood
clotting, normal heart rhythms
Water
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Most important nutrient
Studies show people are
getting enough water from
the liquids and the
moisture content of solid
foods.
To avoid dehydration, use
the thirst signal
Exception is exercise
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Balancing the American Diet
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National Academy of
Sciences created
guidelines for a wellbalanced diet
The ranges allow for
flexibility in planning
diets for individual health
and physical activity
needs
The source of fat calories
is critical
Dietary Reference Intakes describe nutrition standards
1. Estimated Age Requirement (EAR)
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Amount of nutrient meeting the dietary need for half the
people in a specific age and gender group
2. Recommended Dietary Allowance (RDA)
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Daily amount of a nutrient considered adequate to meet
known nutrient needs of almost 98% of all healthy people
in the United States
3. Adequate Intake (AI)
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Recommended amount of intake when EAR and RDA aren’t
available
4. Tolerable Upper Intake Level (UL)
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Highest level of nutrient intake that seems safe for most
healthy people, beyond which exists an increased risk of
adverse effects
Nutrition Standards
Daily Values
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Reference values for nutrients and food
components listed on food-packaging labels
Based on a 2,000 calorie/day diet
Need to be adjusted based on an individual’s
Estimated Energy Requirement
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Average dietary energy intake 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
Food Label with
U.S.
Recommended
Daily Values
Nutrient Analysis
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Keep a 3-day record of all foods and
beverages consumed
 Includes measurements of calories,
carbohydrates, fats, protein,
cholesterol, sodium, vitamins, and
minerals.
Use the food tracker on
choosemyplate.gov
Nutrient Analysis
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Most revealing information
learned in a nutrient analysis
is the source of fat intake
Average daily fat
consumption in the U.S. diet
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About 34% of the total caloric
intake
Much of it from saturated fat
and trans fatty acids, which
increase the risk for chronic
diseases
Achieving a balanced diet
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Vegetables, fruits whole grains and dairy provide
base for healthy diet
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Vegetables and fruits are the sole source of
Phytonutrients which prevent and fight cancer
• When increasing
nutrients from above
food groups, reduce the
intake of low-nutrient
foods
Choosing Healthy Foods
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Learn the nutritive value of
typical foods you eat by
reading food labels
Be aware that there is label
misinformation as the FDA
does not have the
manpower to regularly
check food labels
Healthy eating requires
proper meal planning and
adequate coping strategies
Choosing
Healthy Foods
Vegetarianism
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Diet consisting of foods with vegetable or plant
origin
Five types of vegetarians
1. Vegans – eat no animal products
2. Ovovegetarians – allow eggs in their diet
3. Lactovegetarians – consume foods from the milk
group
4. Ovolactovegetarians – include egg and milk
products in their diet
5. Semivegetarians – do not eat red meat, but eat
fish and poultry, milk products and eggs
Vegetarianism
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Nutrient concerns
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Strict vegans need B12 supplements
Eat foods that possess complementary proteins
Vegetarian diets may also lack vitamin D, riboflavin,
calcium, iron, zinc
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But can be found in certain foods…
Approaches to avoid nutrient deficiency in a
vegetarian diet
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Vitamin D – moderate exposure to the sun or
supplementation
Riboflavin – consume green, leafy vegetables,
whole grains and legumes
Calcium – consume fortified soybean milk or
orange juice, calcium-rich tofu and some cereals
Iron – consume whole grains, dried fruits, nuts
and legumes
Zinc – consume whole grains, wheat germ, beans,
nuts and seeds
Soy products contain antioxidants
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Soy consumption is recommended as a
replacement to meat consumption, but further
research is needed to understand impact of soy
on women
Current recommendations in the University of
California at Berkeley Wellness Letter:
1. Do not exceed 3 servings per day
2. Limit intake to a few servings per week if you
have or have had breast cancer
3. Avoid soy supplements because they may
contain more isoflavones than soy foods
Probiotics
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Healthy microbes (bacteria) that help break down
foods and prevent disease-causing organisms
from settling in the intestines
Example:
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Yogurts with Lactobacillus bifidus, Lactobacillus
acidophilus and inulin
Avoid yogurt with added fruit jam, sugar, and
candy
Advanced Glycation End Products (AGEs)
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Derivatives of glucose-protein and glucose-lipid
interactions that are linked to aging and chronic
diseases
Decrease consumption of AGEs
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Limit cooking meats at high temperature
Avoid high-fat foods
Increase intake of fruits, vegetables, grains, fish
and low-fat milk products
Cook at home using fresh, unprocessed foods
Avoid browning (frying, broiling and grilling)
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French fries have 8 time the amount of baked
potatoes
Diets from other cultures
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Mediterranean diet
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Focuses on olive oil, red
wine, grains, legumes,
vegetables and fruits, with
limited amounts of meat,
fish, milk and cheese
Reduces rates of heart
disease and cancer
Other ethnic diets also
provide health benefits by
emphasizing intake of
complex carbohydrates and
limited fat-intake
Diets from
Other
Cultures
Nutrient supplementation
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A healthy diet of 1,500 calories contains the
necessary nutrients
Many people take supplements even though
their diet contains sufficient nutrients
Groups who may need nutrient supplementation
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Adults over 60
Individuals on low-calorie diets
Individuals with nutrition deficiencies
Avoid megadosing vitamins – consuming 10
times more than the RDA
Anitoxidants
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Compounds such as vitamins C and E, betacarotene and selenium that prevent oxygen from
combining with other substances in the body to
form harmful compounds
Work best as prevention and progression of
disease, but cannot repair damage that has
already occurred
More research is required to understand the
impact of antioxidants
Antioxidants
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Free radicals attack and damage proteins, lipids, cell
membranes, and DNA
Free radical formation is
enhanced by solar radiation,
cigarette smoke, air pollution,
radiation, some drugs, injury
or infection, chemicals (such
as pesticides), and other
environmental factors
Vitamin supplementation
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Vitamin E
Found in oil-rich seeds and vegetable oils
Little to no research demonstrates benefit
Vitamin C
May offer benefits against heart disease, cancer, and cataracts
Body absorbs the first 200 milligrams per serving or dose and the
rest is excreted
Beta-Carotene
Can be obtained from sweet potatoes, pumpkin, cantaloupe,
squash, kale, broccoli, tomatoes, peaches, apricots
Preferable to receive through food rather than supplementation
Selenium
Take 100-200 mcg daily
One Brazil nut (unshelled) provides 100 mcg
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Top antioxidant foods
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Fruits and vegetables are the richest sources of
antioxidants and phytonutrients
Vitamin supplementation
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Multivitamins
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Vitamin D
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No solid scientific evidence that they decrease risk of
cardiovascular disease or cancer
May be able to fill deficiencies, but don’t provide
energy, fiber, phytonutrients
Best source is 15 minutes of sunshine daily
Vitamin D levels in the blood should be between 50
and 80 ng/mL throughout the year
Folate
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B vitamin that is recommended for all premenopausal women
Benefits of Foods
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Choosing a wide variety of food is the
best strategy to gain nutritional benefits.
Supplements do not supply all of the
nutrients and other beneficial
substances present in food and needed
for good health.
Wholesome foods contain vitamins,
minerals, carbohydrates, fiber, proteins,
fats, phytochemicals, and other
substances not yet discovered.
Many nutrients work in synergy,
enhancing chemical processes in the
body.
Functional Foods
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Foods or food ingredients containing
physiologically active substances that provide
specific health benefits beyond those supplied by
basic nutrition
Different than fortified foods which have been
modified by the addition or increase of nutrients
that either were not present or were present in
insignificant amounts, with the intent of
preventing nutrient deficiencies
Organic Foods
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Is not more nutritious than non-organic food, but
contains fewer pesticides
Created under strict governmental regulations
Cannot use genetically-modified organisms
during the growth process
Genetically modified crops
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Genetically modified food (GM)
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Basic genetic material is manipulated by inserting
genes with desirable traits from one plant, animal
or microorganism into another one to either
introduce new traits or enhance existing ones
No evidence indicates that GM foods are harmful,
but no compelling evidence guarantees that they
are safe
Energy substrates for physical activity
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Two main fuels
Glucose derived from foods is stored as glycogen in
muscles and the liver.
 Fatty acids, the product of the breakdown of fats,
stored as fat in the body
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Amino acids from proteins are used as an energy
substrate when glucose is low.
Energy substrates for physical activity
The body uses Adenosine triphosphate (ATP) for
immediate energy. It is resynthesized in 3 ways:
1. ATP-CP System
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Used in the first few seconds of all-out exercise
2. Anaerobic or lactic acid system
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Used during maximal intensity exercise from 10180 seconds
Produces lactic acid which leads to muscle fatigue
3. Aerobic system
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Used during slow, sustained exercise and requires
glucose, fatty acids and oxygen
Nutrition for athletes
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Supplementation is not required for most
athletes, but increased food intake may be
needed
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Increased protein:
Nutrition for athletes
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Carbohydrate loading replenishes glycogen
storage, used for sustained exercise, greater than
90 minutes
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For exercise 60 minutes or less, 60 percent of
carbohydrate intake should be maintained for the
rest of the day
For exhaustive exercise of several hours a day, 70
percent of carbohydrate intake should be
maintained
Within 30 minutes after exercise, a snack of protein
and carbohydrate enhances re-storage of glycogen
Nutrition for athletes
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Protect against hyponatremia by ingesting extra
sodium prior to the event and replace with 1
gram of sodium per hour during an event
Creatine supplementation
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Creatine is a higher-energy compound that the
cells use to resynthesize ATP during all-out
activities of very short duration
Loading: 20-25 grams/day for 5-6 days split into
four or five doses
Maintenance: 2 grams/day
Bone Health and Osteoporosis
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A condition that leads to
softening, deterioration, or loss
of bone mineral density
Causes disability, fractures, and
even death from medical
complications
About 22 million women in the
U.S. suffer from this condition (16
million do not know they have it)
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Women are especially
susceptible after menopause
when estrogen is no longer
produced
One in 2 women and one in 8
men will suffer from osteoporosis
Bone health and osteoporosis
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Promote bone health through adequate calcium intake
and sufficient physical activity
Calcium supplementation
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Calcium carbonate – not well absorbed without food
Calcium citrate – absorbed without food
Avoid eating an iron-rich meal with calcium supplement
Excessive protein discourages rebuilding of bones
Hormone replacement therapy (HRT)
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Originally provided to decrease bone loss after
menopause
HRT relieves acute symptoms of menopause and
decreases risk of hip fractures and colorectal cancer
HRT was found to increase risk for developing breast
cancer, blood clots, strokes and heart disease
Alternative therapies:
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Synthetic calcitonin
Nonhormonal medications
Selective estrogen receptor modulators
Iron deficiency
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Iron is carried by hemoglobin:
The protein-iron compound in red blood cells that
transports oxygen in the blood
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Deficiency more common in women, endurance
athletes, children and teenagers
Iron levels are assessed through measurement of
blood ferritin:
The form of iron stored in the body
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RDA for adult women is 15-18 mg per day
RDA for adult men is 8-11 mg per day
Iron Deficiency
2010 Dietary Guidelines for Americans
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Two key concepts
1. Balance calories with physical activity to sustain
a healthy weight
2. Focus on consuming nutrient-dense foods and
beverages
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Fruits and vegetables
Whole grains
Fat-free and low-fat dairy products
Seafood
Visit: www.dietaryguidelines.gov
2010 Dietary
Guidelines for
Americans