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Chapter 2
Lecture Slides
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Essential Nutrients and Recommended
Nutrient Intakes
• Foods we eat
– Essential nutrients
– Nonessential nutrients
– Other substances
• Amounts of nutrients recommended
– Dietary Reference Intakes (DRIs)
What are essential nutrients?
• Essential nutrients cannot be produced in adequate
quantities in body and must be consumed in diet
• Six major classes of essential nutrients
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Carbohydrate
Fats
Protein
Vitamins
Minerals
Water
Essential or probably essential nutrients
• Carbohydrates
– Fiber and sugar and starches
• Fats
– Essential fatty acids (Linoleic and alpha-linolenic)
• Protein
– 9 essential amino acids
• Vitamins
– 9 water soluble and 4 fat soluble
• Minerals
– Over 20 minerals
• Water
Essential nutrients
• Macronutrients (gram quantity)
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Carbohydrate
Fat
Protein
Water
• Micronutrients (milligram or microgram quantity)
– Vitamins
– Minerals
Essential nutrients
• Essential for life
• Some foods contain all six classes of nutrients
– Whole wheat bread
• Some foods contain only one class
– Refined table sugar
Figure 2.1
What are nonessential nutrients?
• Nonessential nutrients (Dispensable nutrients)
– Found in food but may also be formed in the body
– Creatine is an example
• Needed for one form of energy production
• Found in food, mainly animal foods
• Produced in the body from amino acids
• Non-nutrients
– Found naturally in or added to foods
• Plant sterols
• Caffeine
Examples of nonessential nutrients and
other substances found in food
• Nonessential nutrients
– Carnitine
• Food drugs
– Caffeine
• Phytochemicals
– Flavonoids
• Extracts
– Ginseng
• Antinutrients
– Tannins
How are recommended dietary intakes
determined?
• Food and Nutrition Board, Institute of Medicine of
the National Academy of Sciences
– 1941: First set of Recommended Dietary Allowances (RDA)
• Dietary Reference Intakes (DRIs) represent the
current standards
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Recommended Dietary Allowance (RDA)
Adequate Intake (AI)
Acceptable Macronutrient Distribution Range (AMDR)
Tolerable Upper Intake Level (UL)
Estimated Average Requirement (EAR)
Estimated Energy Requirement
Estimated Average Requirement (EAR)
• The EAR represents a nutrient intake that is
estimated to meet the requirement of half the
healthy individuals in a population
• The EAR is used to establish the RDA
• The RDA is some multiple of the EAR
Recommended Dietary Allowance (RDA)
• The RDA represents the average daily dietary intake
that is sufficient to meet the nutrient requirement of
nearly all (97%-98%) healthy individuals in a
population.
• The RDA is to be used as a guide for the individual
Acceptable Macronutrient Distribution
Range (AMDR)
• The AMDR is defined as a range of intakes for a
particular energy source (macronutrient).
• The AMDR is expressed as a percentage of total
energy intake.
– Carbohydrate: 45-65%
– Fat: 20-35%
– Protein: 10-35%
Tolerable Upper Intake Level (UL)
• The UL is the highest level of daily nutrient intake
that is likely to pose no risks of adverse health
effects to most individuals in the general population.
• Consider it a maximum for daily intake of a specific
nutrient on a long-term basis.
Estimated Energy Requirement (EER)
• The EER is an estimate of the amount of energy
needed to sustain requirements for daily physical
activity.
• Discussed in detail in Chapter 3.
• Useful for weight control discussed in chapter 11.
Interpreting the DRI
• Used to assess adequacy of dietary intake
• Used to plan diets for individuals and groups
• Designed to ensure adequate nutrition for most
people in a population
– Diet on any day is not necessarily deficient if RDA is not
obtained
– Intake should be averaged over a 5-8 day period
• Does not inform us of what specific foods to eat
• Note: Another term, the Daily Value (DV) is used on
food labels, discussed later.
The Balanced Diet and Nutrient Density
• The balanced diet
– Variety
– Moderation
• Concept
A balanced diet will provide the required amounts of
essential nutrients
The Balanced Diet and Nutrient Density
• The balanced diet
– Variety
– Moderation
The Balanced Diet
• Individuality
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Age
Gender
Health status
Sport
What foods should I eat to obtain the
nutrients I need?
• History
– Basic Seven
– Basic Four
• Current status
– Food Guide for Americans
– Revised every 5 years
– MyPyramid Food Guide (2005)
• First guide to include physical activity
• Other guides
– The Food Exchange System
• American Dietetic and American Diabetes Associations
Current food groups
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Milk, yogurt and cheese
Meat, poultry, fish, dry beans, eggs, nuts
Bread, cereal, rice, pasta
Vegetables
Fruits
Fats, oils, sweets (Not an official food group)
Nutrients in different food groups
• Milk, yogurt, cheese
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Calcium
Protein
Riboflavin
Vitamins A, D
• Meat, poultry, fish, dry beans, eggs, nuts
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Protein
B vitamins
Iron
Zinc
Nutrients in different food groups
• Bread, cereal, rice, pasta
– B vitamins
– Iron
– Fiber
• Vegetables
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Vitamin A (carotene)
Vitamin C
Iron
Fiber
Nutrients in different food groups
• Fruits
– Vitamin A (carotene)
– Vitamin C
– Fiber
• Fats, oils
– Vitamin A
– Vitamin D
– Vitamin E
What is the MyPyramid food guide?
• Steps to a healthier you
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Variety
Proportionality
Moderation
Activity
Gradual improvement
Personalization
Figure 2.3
MyPyramid
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Access at www.MyPyramid.gov
Enter demographic data
Develop an individualized food plan
Use MyPyramid Tracker for detailed assessment
– Excellent dietary assessment tool
– Analyzes current diet and physical activity
• Tracks both for up to a year
• Obtain detailed information about each food group
• MyPyramid for Kids is available
• Information for health professionals
Figure 2.4
Key food group messages from the
Dietary Guidelines and MyPyramid:
Focus on fruits.
Vary your veggies.
Get your calciumcalcium-rich foods.
Make half your grains whole.
Go lean with protein.
Know the limits on fats, salt, and sugars.
MyPyramid serving size
• Milk
– 1 cup of milk or yogurt
– 1.5 ounces of natural cheese
– 2 ounces of processed cheese
MyPyramid serving size
• Meat
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1 ounce of cooked lean meat, poultry or fish
0.25 cup of cooked dry beans
1 egg
1 tablespoon peanut butter
MyPyramid serving size
• Grains
– 1 slice of bread
– 1 ounce of ready-to-eat cereal
– 0.5 cup of cooked cereal, rice, or pasta
MyPyramid serving size
• Vegetable
– 1 cup of raw, leafy vegetables
– 0.5 cup of other vegetables, cooked or chopped raw
– 1 cup of vegetable juice
MyPyramid serving size
• Fruit
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1 medium apple, banana, or orange
1 cup of chopped, cooked, or canned fruit
1 cup of fruit juice
0.5 cup dried fruit
MyPyramid serving size
• Oil
– 1 teaspoon
MyPyramid Tracker
A tool for those
desiring a more
advanced analysis of
their food intake and
physical activity
What is the Food Exchange System?
• Developed by the American Dietetic Association and
American Diabetes Association
• Foods in an exchange contain similar nutrient and
caloric value
• Six food exchanges
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Milk exchange
Meat and meat substitutes exchange
Starch exchange
Fruit exchange
Vegetable exchange
Fat exchange
Food Exchange Groups
Food Exchange
Carbohydrate
Fat
Protein
Calories
Skim/very low fat
12
0- 3
8
90
Low fat
12
5
8
120
Whole
12
8
8
150
Very lean
0
0- 1
7
35
Lean
0
3
7
55
Medium fat
0
5
7
75
High fat
0
8
7
100
Starch (1 oz; ½ cup)
15
0- 1
3
80
Fruit (1 medium; ½ cup)
15
0
0
60
Vegetable (1/2 cup)
5
0
2
25
Fat (1 teaspoon)
0
5
0
45
Milk (1 cup)
Meat/substitutes (1 oz)
Carbohydrate, fat and protein in grams per serving
1 g carbohydrate = 4 Calories; 1 gram fat = 9 Calories; 1 gram protein = 4 Calories
What is the key-nutrient concept for
obtaining a balanced diet?
• The key-nutrient concept indicates that obtaining adequate
amounts of 8 key nutrients from natural, wholesome foods
will provide adequate amounts of other essential nutrients.
Eight key nutrients and significant food
sources from plants and animals
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Protein
Vitamin A
Vitamin C
Thiamin
Riboflavin
Niacin
Iron
Calcium
Beans, Peas
Color vegetables
Citrus fruits
Grains
Grains
Grains
Beans, peas
Spinach, kale
Meat, fish
Fortified milk
Liver
Pork, ham
Milk, cheese
Meat, poultry
Meat, liver
Milk
Eight key nutrients and significant food
sources from plants and animals
What is the concept of nutrient density?
• Foods that contain a significant amount of a specific
nutrient compared to its caloric content have a high
nutrient density.
• May be referred to as Quality Calories.
Figure 2.6
Nutrient density
• Yale University has developed an Overall Nutritional
Quality Index (ONQI) which rates foods on a scale
from 1 to 100 based on nutrient content and health
concerns.
• Broccoli scores 100, while soda scores 1.
www.nuval.com
Will use of MyPyramid Food Guide or the Food
Exchange System guarantee me optimal
nutrition?
• Nutritionists indicate that the recommendations in
MyPyramid are remarkably consistent with the
various recommendations to control most chronic
diseases.
• MyPyramid itself does not indicate what specific
foods to eat for health, but does provide specific
guidelines on its website.
• Healthy eating focuses on the total diet, not one
food.
• Select foods with lower amounts of fat and sugar.
Healthy Eating
• Cost of healthy eating
– Energy-dense foods high in sugar and fat
• $1.76 for 1,000 Calories
– Fruits, vegetables and other healthier foods
• $18.16 for 1,000 Calories
• Reducing the cost of healthy eating
– Choose seasonal fruits and vegetables
– Capitalize on store specials on fresh chicken, fish
• Separate into smaller packages and freeze
– Purchase whole grain products in bulk
– Buy bags of frozen vegetables; cheaper and less spoilage
Healthful Dietary Guidelines
• Nutritional guidelines developed to help minimize
the risk of various chronic diseases.
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Coronary heart disease
Stroke
Cancer
Diabetes
Osteoporosis
Obesity
High blood pressure
What is the basis underlying the development of
healthful dietary guidelines?
• Concept that the development of most chronic diseases may
be associated with either deficiencies or excesses of various
nutrients or food constituents in the diet.
• Earlier guidelines based on epidemiological research, which
may have led to some erroneous recommendations.
• Current guidelines are evolving as more long-term
experimental studies are conducted.
• The Optimal Macronutrient Intake Trial to Prevent Heart
Disease (OmniHeart)
– Type of carbohydrate, fat and protein could have favorable effects
• No absolute proof, but prudent recommendations
What are the recommended dietary guidelines
for reducing the risk of chronic diseases?
• Synthesis of various reports from professional and
governmental health organizations
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American Cancer Society
American Diabetes Association
American Dietetic Association
American Institute of Cancer Research
Harvard School of Public Health
United States Department of Agriculture
United States Department of Health and Human Services
Prudent Recommendation
1. Balance the food you eat with physical activity to
maintain or achieve a healthy body weight.
Prudent Recommendation
2. Eat a nutritiously adequate diet consisting of a wide variety of
nutrient-rich foods.
Prudent Recommendation
3. Choose a diet moderate in total fat, but low in saturated and
trans fats and cholesterol.
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Choose plant oils or other healthy fats
Eat less meat with high fat content; choose lean poultry
Eat more fish
Eat only several eggs per week
Eat fewer high-fat dairy products
Eat less butter; use soft or specialty margarines
Eat fewer commercial baked goods
Limit consumption of fast foods
Use food labels to help you select foods low in fat
Broil, bake or microwave instead of cooking in oil
Prudent Recommendation
4. Choose a plant-rich diet with plenty of fruits and vegetables,
whole-grain products, and legumes, foods which are rich in
complex carbohydrates, phytochemicals, and fiber.
Fruits and Veggies: More matters
Prudent Recommendation
5. Choose beverages and foods to moderate your
intake of added sugars.
– Moderate intake
• Sodas
• Juice drinks
• Fruit juices
– Drink more
• Tap water
Prudent Recommendation
6. Choose and prepare foods with less salt and sodium.
– Get rid of your salt shaker
– Reduce the consumption of obviously high-salt foods
– Check food labels for sodium content
– Eat more fresh fruits and vegetables
– Use fresh herbs or spices that do not contain sodium
– Use lite salt
Prudent Recommendation
6. Choose and prepare foods with less salt and sodium.
Prudent Recommendation
7. If you drink alcoholic beverages, do so in moderation.
Prudent Recommendation
8. Maintain protein intake at a moderate, yet adequate level,
obtaining much of your daily protein from plant sources
complemented with smaller amounts of fish, skinless
poultry, and lean meats.
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Current protein intake in the United States is
• 70 percent animal protein
• 30 percent plant protein
Recommended protein intake is
• 30 percent animal protein
• 70 percent plant protein
Prudent Recommendation
9. Choose a diet adequate in calcium and iron. Individuals
susceptible to tooth decay should obtain adequate fluoride.
Prudent Recommendation
10. Practice food safety, including proper food preservation and
preparation.
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Store foods properly
Wash hands thoroughly
Avoid charring of meats
Prudent Recommendation
11. Consider the benefits and risks of food additives and dietary
supplements.
Prudent Recommendation
12. Enjoy your food! Eat what you like, but balance it within
your overall healthy diet.
Vegetarianism
What types of food does a vegetarian eat?
• Vegan
– No animal products at all
• Ovovegetarian
– Eats eggs
• Lactovegetarian
– Eats dairy products
• Ovolactovegetarian
– Eats eggs and dairy products
• Pescovegetarian
– Eats fish
• Semivegetarian
– Eat fish and white poultry meat
What are some of the nutritional concerns
with a vegetarian diet?
• Calories
– Inadequate Calories
• May be a problem for children and athletes
• May be advantage for weight control
• Vitamins
– B12 not found in natural plant foods
• Minerals
– Diets may be low in iron, calcium and zinc
• Protein
– Grains low in lysine; legumes low in methionine
– Vegan diet should contain complementary proteins
Combining foods for protein complementarity
Is a vegetarian diet more healthful than a
nonvegetarian diet?
• Nutrient density
Is a vegetarian diet more healthful than a
nonvegetarian diet?
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Low fat and cholesterol
High fiber content
Low caloric content
High vitamin
High phytochemical content
– Nutraceuticals
Potential health benefits of antioxidants
and phytochemicals
Eating the colorful way
How can I become a vegetarian?
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Eat more fruits, vegetables and whole grains
Become a part-time vegetarian. Eat less red meat.
Become a semivegetarian.
Become an ovolactovegetarian
Eat a vegan diet a couple of days each week
Use these websites
– www.Goveg.com
– www.Thevegetariansite.com
– www.Vegan.com
Will a vegetarian diet affect physical
performance potential?
• Limited research with vegetarian diets and exercise
performance
• Some world class athletes have been vegetarians
• Pros
– Rich in carbohydrates
– Fortified foods may provide adequate vitamins and minerals
– Plant and animal protein appear to be adequate
• Cons
– At risk for non-anemic iron deficiency or iron deficiency anemia
– Lower muscle creatine levels may possibly affect performance
Consumer Nutrition: Food Labels and Health Claims
What nutrition information do food labels provide?
• Nutrition Facts
Figure 2.7
Consumer Nutrition: Food Labels and Health Claims
What nutrition information do food labels provide?
• Nutrition Facts
How can I use this information to select a
healthier diet?
• The Daily Value (DV)
– Based on some of the DRI values
– Those listed based on 2,000 Calorie intake (Adult female)
• The % of the DV on the label is for a 2,000 Calorie intake
– Some information for 2,500 Calorie intake (Adult male)
– Some DV values are outdated as they are based on earlier
RDA values (U. S. RDA)
Daily Value
• The DVs are based pm certain minimum and
maximum allowances, including the following for a
2,000 Calorie diet:
Figure 2.10
Definitions for comparative and absolute
nutrient claims on food labels
Definitions for comparative and absolute
nutrient claims on food labels
Definitions for comparative and absolute
nutrient claims on food labels
Definitions for comparative and absolute
nutrient claims on food labels
Definitions for comparative and absolute
nutrient claims on food labels
Definitions for comparative and absolute
nutrient claims on food labels
Definitions for comparative and absolute
nutrient claims on food labels
Definitions for comparative and absolute
nutrient claims on food labels
Definitions for comparative and absolute
nutrient claims on food labels
Definitions for comparative and absolute
nutrient claims on food labels
Cool Website
• www.Cfsan.fda.gov/labelman
The FDA provides a program, Make Your
Calories Count, featuring the animated
character Labelman, to help people read food
labels to plan a healthy die while balancing
caloric intake.
What health claims are allowed on food
products?
What are functional foods?
• Functional foods are food products designed to
provide health benefits beyond basic nutrition, the
benefits being attributed mostly to vitamins,
minerals, phytochemicals, and herbals.
• Natural foods may be fortified
– Example: Calcium-fortified orange juice
• The ADA indicates some may have a beneficial effect
if consumed within a varied diet on a regular basis.
• Some products may not be healthful
– Example: Sugar drink with added vitamins
Consumer Nutrition: Dietary Supplements
and Health
What are dietary supplements?
Defined by the Dietary Supplement Health and Education Act
(DSHEA) of 1994, a dietary supplement is a food product,
added to the total diet, that contains at least one of the
following ingredients.
– Vitamin
– Mineral
– Herb or botanical
– Amino acid
– Metabolite
– Constituent
– Extract
– Combination of any of these ingredients
Dietary Supplements
• Like foods, dietary supplements must carry labels, or
Supplement Facts.
Will dietary supplements improve my
health?
• Best nutritional advice is to obtain nutrients through
natural, wholesome foods.
• Some may benefit from dietary supplements
– Example: Vitamins for elderly, women of childbearing age
• Most herbals not adequately researched
• Products often are mislabeled
• Supplements may carry structure/function claims
– This statement has not been evaluated by the FDA.
• Burden of proof is on the FDA
• Improvements in labeling expected in 2010
Dietary Supplements
Can dietary supplements harm my health?
• Possibly. Users of dietary supplements may
– disregard other very important lifestyle behaviors.
– provide a false sense of security, thus one may not eat
right
– take excessive dosages, which may be harmful.
– may use supplements as alternative medicine, and not
seek proper medical advice.
– take supplements that are contaminated.
– take potentially harmful supplements, such as ephedra.
Dietary Supplements
• Some general safeguards by Consumers Union
– Before trying a supplement to improve your health, try
changing your diet and lifestyle first
– Check with your doctor, especially with herbals.
– Buy standardized products; USP rating is helpful
– Use only single ingredient supplements
– Be alert to positive and negative effects
– Stop taking the supplement if you experience problems;
report problems to physician or local health authorities.
Cool Website
http://dietarysupplements.nlm.nih.gov
Check dietary supplements by specific brands or
active ingredients. Indicates uses for the product.
Provides list of research studies regarding
effectiveness.
Consumer Nutrition:
Food Quality and Safety
• FDA Center for Food Safety and Applied Nutrition
– Regulates food quality and safety
– However, foods not necessarily risk free or high quality
• Food safety is in 2005 Dietary Guidelines for
Americans
Is current food biotechnology
effective and safe?
• Historical aspects
– Breeding of plants and animals for higher quality foods
• Genetic engineering; genetic modification (GM)
– Rice designed to contain more beta-carotene
– Salmon engineered to grow faster and larger
• Foods regulated by FDA, USDA and EPA
• 70% of foods in typical supermarket contain at least
one GM ingredient
• GM foods generally recognized as safe
– Not labeled in US except under certain circumstances
Do pesticides or herbicides in food present
significant health risks?
• Plants contain natural phytochemicals that function
as herbicides and pesticides
• Synthetic herbicides and pesticides
– Used to protect plants
– Function differently in the human body
– May cause health problems
• Occupational exposure (farm workers)
• Current scientific reports
– Trace amounts in foods not harmful to adults
– Chronic exposure may cause health problems in children
Pesticides and Herbicides
Advice based on current research:
• Avoid direct skin contact or breathing
• Prepare foods carefully; wash thoroughly
• Eat less animal fat and fish from contaminated
waters
• Buy fruits and vegetables locally in season
• Eat a wide variety of foods
• Buy certified organic foods
Pesticides in Foods
The Dirty Dozen and the Clean Dozen
Are organic foods
safer and healthier choices?
• Foods that are 95-100%
organic can carry the
USDA organic label.
• Foods that contain at
least 70% organic
ingredients may use
Made With Organic
Ingredients, but cannot
use the label.
Organic Foods vs Conventional Foods
• Pesticides
– Organic foods contain fewer pesticides
– Significance of the difference, however, is questionable
• The clean dozen have few pesticides
• Bacteria
– Bacteria levels in organic fruits, vegetables and chicken
similar to conventional foods
– Organic does not mean safe
• Nutritional value
– Differences are questionable
– Organic junk foods, such as organic soda
Does commercial food processing
affect food quality and safety?
• Potential beneficial effects
– May preserve high nutrient value (flash frozen)
– Nutrients may be added (enriched; fortified)
• Potential harmful effects
– Adding too much sugar and fat
– Addition of questionable additives
– Removing essential nutrients such as vitamins and
minerals
– Inadvertent inclusion of bacteria
Does home food processing
affect food quality and safety
• Tips for food processing at home
– Keep most fruits and vegetables in the refrigerator
– Keep frozen foods frozen until ready for use
– Keep milk, grains in opaque containers
• Prevent destruction of riboflavin
– Steam or microwave vegetables in little water
– Avoid cooking with high temperatures
• Loss of water-soluble vitamins in boiling water
– Avoid excess cooking of foods
• Formation of acrylamide and heterocyclic amines (HCA)
What is food poisoning?
• Food poisoning is caused primarily by consuming
foods contaminated with certain bacteria.
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Salmonella
Escherichia (E. coli)
Staphylococcus
Clostridium
Campylobacter
Listeria
• Food poisoning is the major health problem
associated with home food processing.
Food poisoning
• Most common commercial sources of bacteria
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Raw and undercooked meat and poultry
Raw or undercooked eggs
Raw or undercooked shellfish
Contaminated produce
Improperly canned foods
• Most common home sources of bacteria
– Improper food preparation
– Poor sanitation
Food poisoning
• Consumers Union
– 83 percent of whole chicken broilers bought nationwide,
even premium and organic broilers, harbored
Campylobacter or Salmonella
– Major outbreak associated with fresh spinach and E. coli;
31 cases of kidney failure and 3 deaths
1. Food poisoning
• Most common symptoms
– Nausea
– Vomiting
– Diarrhea
• More severe symptoms. Seek medical help.
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Headache and stiff neck
Bloody or prolonged diarrhea (3 days)
Fever more than 24 hours
Sensations of weakness, numbness, tingling in legs
Preventing food poisoning
• Commercial food preparation
– Use of food preservatives
– Irradiation
Preventing food poisoning
• Home food preparation
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Wash hands thoroughly before and during food prep
Treat all raw animal foods as if contaminated
Wash all fruits and vegetables thoroughly
Clean thoroughly all utensils used in food preparation with
hot soapy water; microwave sponges and other utensils
Use a clean preparation surface
Do not use canned foods that are damaged or bulging
Cook all meat, poultry, seafood and eggs thoroughly
Store heated foods promptly in the frig or freezer
Use leftovers in a few days; if in doubt, throw it out
Are food additives safe?
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More than 40 purposes for the use of additives
Add flavor
Enhance color
Improve texture
Preserve the food
Food additives
• Generally recognized as safe (FDA approval)
– Acceptable Daily Intake (ADI) developed for some foods
– Additives may used only In specific foods for specific
purposes
– The Delaney Clause
• In general, most food additives are regarded as safe.
However, some consumer protection groups stress
caution with some.
Cool Website
www.cspinet.org/reports/chemcuisine.html
• The Center for Science in the Public Interest has
developed a guide to safety of food additives,
including the following five categories:
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Safe
Cut back
Caution
Certain people should avoid
Everyone should avoid
Healthful Nutrition: Recommendations for
Better Physical Performance
• Purposes of food for sport performance
– Provide energy
– Regulate metabolic processes
– Promote growth and development
• Nutrition for training
• Nutrition for competition
What should I eat during training?
• Ron Maughan indicates that the main role of
nutrition for the athlete may be to support
consistent intensive training.
• Chris Carmichael notes that athletes need to match
their nutritional intake to the demands of training.
Diet during training: Some considerations
• The Prudent Healthy Diet
– May serve as the basic diet plan
• The chronic training effect
– Focus on adequate intakes of nutrients in early training
• Timing of nutrient intake
– John Hawley notes that the beneficial effects of training
are believed to occur during the recovery period
• Breakfast is an important meal for the athlete
Breakfast for the athlete
• A balanced breakfast provides a significant amount
of Calories and other nutrients in the daily diet
– Skim milk, whole grain cereal, poached egg, toast, OJ
• May help maintain feeling of satiety in the morning
• Skipping breakfast is comparable to a small fast
– Possible hypoglycemia
• May enhance academic performance
When and what should I eat
just prior to competition?
• Major goals of the precompetition meal involve
timing and composition
– Allow the stomach to be relatively empty at the start.
– Help to prevent or minimize gastrointestinal distress.
– Help avoid sensations of hunger, lightheadedness, or
fatigue
– Provide adequate energy supplies, primarily carbohydrate,
in the blood and muscles.
– Provide an adequate amount of body water.
Examples of precompetition meals
Some meal plans for competition
What should I eat during competition?
• In most sports, only fluids and carbohydrates may be
necessary
• Specific nutrients will be discussed throughout the
course as merited
What should I eat after competition?
• In general, a balanced diet will meet nutritional
needs of most athletes.
• Carbohydrate and fluids may be important,
particularly for competition on the same or following
day.
• Protein intake will be discussed in chapter 6.
Should athletes use
commercial sports foods?
• Sports foods may be convenient and appropriate
before, during and after competition or training
• Should not be used as a substitute for a healthy diet
• Types of products
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Liquid sports meals
Sports bars
Sports gels and candy
Sports supplements
How can I eat more nutritiously while
traveling for competition?
• Carry your own food
How can I eat more nutritiously while
traveling for competition?
• Select healthful foods at restaurants, supermarket take-out
buffets, and fast-food establishments
How do gender and age influence nutritional
requirements for enhanced physical performance?
• Gender
– Few differences in nutritional needs of male and female
athletes
– Female endurance athletes may oxidize more fat
– Adolescent and young females need more iron
– Eating disorders more common in females
• Age
– Young athletes may need more Calories, protein, calcium
– Older athletes need fewer Calories, more vitamins B12 and
D, and calcium
– Both need to use caution with exercise in the heat
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