2. 7-2
Why do you need to know
about nutrition?
• Nutrition:
– The science of certain food substances
• Important terminology
– nutrition - diuretics
– diet - nutrient density
– nutrients - requirement
– deficiencies - recommendations
– over-nutrition
3. 7-3
Basic Principles of Nutrition
• Diet refers to food selection
• Nutrients serve three major roles:
– Growth, repair and maintenance of all body
cells
– Regulation of body processes
– Supply of energy for cells
• Some nutrients can be made by the body
– Essential nutrients must be supplied by an
individual’s diet
4. 7-4
• 6 major nutrients:
– Carbohydrates
– Fats
– Protein
– Water
– Minerals
– Vitamins
• If all necessary nutrients are not brought
into the body, nutritional deficiencies may
develop
Macronutrients
Micronutrients
5. 7-5
• Overnutrition
– Eating too much food or specific nutrients
– Common problem in the United States
– Can lead to obesity
• Energy for the body
– Energy value of food is measured in calories
– Carbohydrates = 4 calories per gram
– Fat = 9 calories per gram
– Protein = 4 calories per gram
– Alcohol = 7 calories per gram
7. 7-7
Carbohydrates (CHO)
• Provides body with energy
– While body will also run on fat and protein,
CHO is preferred source of energy
• 55% of total caloric intake should be
accounted for by CHO
• Classified into simple (sugars) or complex
(starch, glycogen, fiber)
8. 7-8
• Sugars:
– Simple carbohydrates that occur as single or
double-sugar chemical units
– Glucose (blood sugar) is needed to fuel cells
– Must be careful not to consume too much
sugar in diet (empty calories)
• Starches:
– Complex carbohydrates (long glucose chains)
– Found in cereal grains, potatoes, and beans
– Glycogen is broken down and released as
glucose in the body when necessary
9. 7-9
• Fiber:
– Helps individuals avoid constipation
• Low fiber diets are blamed for intestinal problems
– Also may be helpful in lowering blood
cholesterol levels, which are a major risk
factor for cardiovascular disease
– Most forms are complex carbohydrates
– Sources
• Dietary and functional fiber
• Fruits, vegetables, whole grain breads and cereals,
nuts, beans, and peas
10. 7-10
Fats
• Extremely important in one’s diet
• Extra calories consumed as
carbohydrates, proteins and fats can all be
converted into triglycerides and stored for
future use
• Stored fat serves multiple functions:
– Serves to cushion organs
– Provides energy to muscles
11. 7-11
• Saturated vs. unsaturated fats:
– Saturated fats are derived primarily from
animal products
• Found in meat (pork, chicken, beef), eggs, and
dairy products
• Also can be found in coconut and palm oils
• Increase blood cholesterol levels
– Unsaturated fats are liquid at room
temperature
• Contain omega-3 and omega-6 fatty acids
• Found in vegetable and fish oils
• Tend to be better for an individual
12. 7-12
• Cholesterol:
– Fat-related substance found in animal foods
– Believed to be responsible for creating blocked
arteries
– If enough is not consumed, your body will produce it
naturally
• Trans fatty acids:
– Resemble saturated fatty acids
– Results in hardening oils
– Will boost levels of bad cholesterol
– No safe level as there is no health benefit
13. 7-13
• Fat intake:
– Total fat consumption vs. consuming specific
fats
– Makes up 40% of total calories consumed by
Americans
• Recommended levels (25-30%)
– Cholesterol recommended levels = 300mg
– Recommendations on reducing fat intake may
be partially responsible for reducing
cardiovascular deaths
14. 7-14
Protein
• Required for growth, repair and
maintenance of cells
• Major constituent of all structures and
organs of the body
• Not a primary source of energy
• Greater need for protein during periods of
growth, breast feeding, active body-
building
15. 7-15
• Recommendations:
– 0.8 grams/kg of body weight
– Should be approx. 12-15% of caloric intake
• Proteins are composed of smaller sub-units
(amino acids)
– 20 amino acids in the body, 9 must be supplied
by diet
– All are necessary for growth
– Primarily found in animal products, some in
plants
17. 7-17
Water
• Most essential nutrient:
– 60% of the adult body is water
• Required for energy production, maintaining cell
function, and cooling of the body
• Body requires 2.5 liters (10 glasses) daily
• Sports drinks:
– Allows for hydration, electrolyte and energy
replacement
– Better for re-hydrating, water itself can shut off thirst
response and turn on kidney function prematurely
18. 7-18
Vitamins
• Vitamins (13) serve as regulators in many
body processes
• Help to regulate metabolism and energy
production, not a source of energy
• Elderly, alcoholics, and those that restrict
food intake severely are susceptible to
vitamin deficiencies
19. 7-19
• Fat soluble vitamins:
– Vitamins A, D, E, K
– Found in fatty portion of foods and oils
– Not easily eliminated from the body
– Stored in liver and body fat – can make them
potentially toxic
• Water soluble vitamins:
– Vitamin C, B-complex vitamins
– Help to regulate metabolism but cannot be stored
– Each serves a series of roles
20. 7-20
• Antioxidants:
– May prevent premature aging, cancers, heart
disease and other health problems
– Helps protect cells from free radicals
– Includes vitamins A, C, E
– Found in a number of dark green, deep yellow
and orange fruits and vegetables
21. 7-21
Minerals
• More than 20 minerals have essential roles in
the body, including:
– Calcium
– Iron
• Many are stored in liver and bones
• Required for a number of things:
– Bones
– Teeth
– Activating enzymes
– Energy production
– Maintaining water balance
22. 7-22
Production of Energy
• Occurs when cells break down chemical
units of glucose and fats or amino acids
– Must burn energy-supplying nutrients
– Results in heat production and usable energy
for cells to work
– Proportions of nutrients burned depend on
type, duration and intensity of exercise
23. 7-23
Nutrient Dense vs. Junk Foods
• Nutrient dense
– Foods containing considerable amounts of
vitamins, minerals, and proteins in relation to
their caloric content
• Junk foods
– Contain too many calories (through sugar and
fats) in relation to the proportion of vitamins
and minerals
24. 7-24
Nutrient Requirements and
Recommendations
• Requirement:
– Amount of a nutrient that is needed to prevent nutrient deficiency
disease
• Recommendations:
– Takes into account the amount necessary to avoid deficiency
• US Recommended Dietary Allowances (USRDA):
– Allows for comparison of the nutrition of food products
• Dietary Reference Index (DRI)
• Upper intake levels (UL)
• Estimated average requirement (EAR)
• Adequate intake (AI)
25. 7-25
Dietary Guidelines
• Nutrition and health recommendations for
healthy children and adults
• In 2010, more emphasis was placed on helping
consumers build healthier diets
– Emphasizes fruits, vegetables, whole grains, fat-free
or low-fat milk, lean meats/poultry, fish, beans, eggs
and nuts
• Actionable messages include:
– Balance calories
– Foods to increase
– Foods to decrease
26. 7-26
MyPlate
• 2011 campaign that focuses on healthier
eating habits
– Helps consumers build a healthy “plate”
based around fruit, vegetables, grains,
protein, and dairy
– Identifies percentages of different types of
food to eat in a given meal
27. 7-27
Reading Labels
• Lists total calories and
calories from fat per
serving
• Information that is based
on percent daily values
• Provides information on
specific nutrients relative
to % daily values
28. 7-28
What is the role of nutrition in
physical activity?
• Physically active people believe that
certain nutrients can help in achieving
fitness goals/competitive edge
• Sometimes certain foods will be avoided
by athletes
29. 7-29
Nutritional Supplements
• Little evidence that vitamin, mineral or protein
supplementation enhances physical
performance:
– Be a careful consumer
– Generic vitamins and minerals are just as effective
– Don’t be misled by labels
– Consuming more than 150% of the recommended
levels may be unhealthy
– Supplements should not be a substitute for food
30. 7-30
Sugar
• Ingesting large quantities of sugar prior to
activity causes increased glucose in the
blood
• Release of insulin stimulated, allowing
cells to utilize free-circulating glucose,
sparing blood glucose
• Positive effect on performance
• However, some athletes are sensitive to
high CHO feedings and have problems
with increased levels of insulin
31. 7-31
Caffeine
• Central nervous system stimulant found in
carbonated beverages, coffee, tea
• Increases alertness and decreases fatigue
• Too much causes nervousness, irritability,
increased heart rate and headaches
32. 7-32
Alcohol
• Provides energy for the body
• Little nutritional value
• Central nervous system depressant
• Not wise to replace water with alcohol
before, during, or following activity
• Too much alcohol can damage liver and
brain cells
33. 7-33
Herbs
• Safe to ingest as natural medicines with few side
effects (occasional allergic reaction)
• No federal or governmental regulations on
quality or distribution
– Exercise caution with consumption
• Herbs serve as body balancers that work with
functions of the body
• Uses may be general for overall strength and
nutrient support or specific to a condition or
ailment
34. 7-34
The Problem with Eating Fast
Food
• 40-50% of calories consumed in fast food
are fat calories
• Add the “supersize” label and the problem
is compounded
• Some fast food establishments have
worked to broaden their menu to include
healthier options
• Nutritional information is also available for
the consumer
35. 7-35
Pre-event Meal
• Long term food consumption is more
important than immediate consumption
• Purpose should be to provide competitor
with nutrients/energy and fluids for
competitions
– A light (300 calories) meal 2-4 hours before is
encouraged
• Avoid a full stomach and fatty foods
• Preloading with water is also suggested
36. 7-36
Vegetarianism
• Utilizes plants to form foundation of diet
• Economic, philosophical, religious, cultural, or
health reasons
• Diet must be carefully planned
• Total vegetarian (vegan): No animal products
• Lactovegetarian: Consumes plant and milk
products
• Ovolactovegetarian: Consumes plant, milk, and
egg products
• Semivegetarian: Does not consume red meats
37. 7-37
Food Safety
• Must be careful both with food preparation and
consumption
• Foodborne illness:
– Result of bacteria in food
– Raw foods are most common source due to lack of
sterilization
• Can happen in your kitchen if food left out for 2
or more hours at room temperature
• Treatment:
– Increase fluid intake; hospitalization if more serious