Download Nutrients

The Role
of Nutrition
in Our Health
Chapter 1
Test Yourself
1.
2.
3.
4.
A calorie is a measure of the amount of fat in
a food. T F
Proteins are not a primary source of energy
for our bodies. T F
All vitamins must be consumed daily to
support optimal health. T F
The Recommended Dietary Allowance is the
maximum amount of a nutrient that people
should consume to support normal body
functions. T F
What is Nutrition?
Nutrition is a relatively new discipline of science.
Nutrition: the study of food, including
 How
food nourishes our bodies
 How food influences our health
Digestion
Absorption
Utilization Excretion
How Does Nutrition Contribute to Health?
Nutrition contributes to
wellness.
Wellness: more than
absence of disease
Many factors contribute to an
individual’s wellness. Primary
among these are:


Nutrition
Physical activity
How Does Nutrition Contribute to Health?
Healthful diet is part of disease prevention
How Does Nutrition Contribute to Health?
How Does Nutrition Contribute to Health?
Nutrition is so important it has become a national
goal to promote optimal health and disease
prevention.
Goals of Healthy People 2020 – this is a health
promotion and disease prevention plan for the
United States.
Increase quality and years of healthy life
2. Eliminate health disparities
1.
How Does Nutrition Contribute to Health?
Obesity is a growing problem in the U.S.
Note the states in dark “red” which indicates a prevalence
of obesity >30%
What Are Nutrients?
Nutrients: chemicals in foods that our bodies use for
energy and to support the growth, maintenance, and
repair of our tissues. Six groups of nutrients:
1.
2.
3.
4.
5.
6.
Carbohydrates
Lipids
Proteins
Vitamins
Minerals
Water
What Are Nutrients?
Essential nutrients: nutrients for which specific
biological functions have been identified, and which
our bodies cannot make enough of to meet our
biological needs
♦
Essential nutrients must be obtained from our diet
♦
Examples: Vitamin C, Calcium, Thiamin
What Are Nutrients?
Macronutrients: nutrients required in relatively
large amounts.
 Carbohydrates,
lipids, proteins
 Provide energy to our bodies
Micronutrients: nutrients required in smaller
amounts.
 Vitamins
and minerals
What Are Nutrients?
Organic nutrients: nutrients contain an element
of carbon that is an essential component of all
living organisms
 Carbohydrates,
lipids, proteins, vitamins
Inorganic nutrients: nutrients that do not
contain carbon
 Minerals
and water
Energy From Nutrients
We measure energy in kilocalories (kcal).
Kilocalorie: amount of energy required to raise
the temperature of 1 kg of water by 1oC.
On food labels, “calorie” actually refers to
kilocalories.
Carbohydrates
•Primary source of fuel for the body, especially
for the brain and physical activity.
•Provide 4 kcal per gram.
Carbohydrates are found in grains (wheat, rice),
vegetables, fruits, and legumes (lentils, beans,
peas), milk products.
Lipids - triglycerides, phospholipids, sterols
•Insoluble in water.
•Provide 9 kcal per gram.
•An important energy source during rest or
low intensity exercise.
•Stored as adipose tissue (body fat) – major
form of stored energy.
•Foods containing lipids also provide fatsoluble vitamins and essential fatty acids.
Proteins
•Proteins are chains of amino acids.
•Support tissue growth, repair, and
maintenance.
•Proteins can supply 4 kcal of energy per
gram, but are not a primary energy
source.
•Proteins are an important source of
nitrogen.
Vitamins
Vitamins are organic molecules that assist in
regulating body processes:




critical in building and maintaining healthy
bones and tissues
support immune system
ensure healthy vision
Many can be destroyed by heat and oxidation
Vitamins do not supply energy to our bodies;
however, many vitamins act as coenzymes
for energy producing reactions
Vitamins
Type
Names
Distinguishing Features
Fat Soluble
A,D,E, and K
•Soluble in fat
•Stored in the human body
•Toxicity can occur from
consuming excess
amounts, which
accumulate in the body
Water Soluble
C, B-vitamins (thiamin,
riboflavin, niacin, vitamin
B6, vitamin B12,
pantothenic acid, and
folate)
•Soluble in water
•Not stored to any extent
in the human body
•Excess excreted in urine
•Toxicity generally occurs
as a result of vitamin
supplmentation
Minerals
Minerals are inorganic
substances required for body
processes.
Minerals have physiological
functions, such as fluid
regulation, energy production,
bone structure, muscle
movement, and nerve
functioning.
Minerals
Our bodies require at
least 100 mg per day of
the major minerals
such as:
•Calcium
•Phosphorus
•Magnesium
•Sodium
•Potassium
•Chloride.
We require less than
100 mg per day of the
trace minerals such
as:
•Iron
•Zinc
•Copper
•Selenium
•Iodine
•Fluoride
Water
Inorganic nutrient, essential for survival
Involved in many body processes:
 fluid
balance and nutrient transport
 nerve impulses
 body temperature
 removal of wastes
 muscle contractions
 chemical reactions
Determining Nutrient Needs
Dietary Reference Intakes (DRIs): updated
nutritional standards
 Expand
on the traditional RDA values
 Set standards for nutrients that do not have
RDA values
 Dietary standards for healthy people only
 For preventing deficiency diseases and
reducing chronic diseases
Determining Nutrient Needs
Determining Nutrient Needs
Estimated Average
Requirement (EAR)

The average daily intake
level of a nutrient that will
meet the needs of half of
the healthy people in a
particular category

Used to determine the
Recommended Dietary
Allowance (RDA) of a
nutrient
Determining Nutrient Needs
Recommended Dietary
Allowances (RDA)

The average daily intake
level required to meet the
needs of 97 – 98% of
healthy people in a
particular category
Determining Nutrient Needs
Adequate Intake (AI)
 Recommended
average daily intake level for a
nutrient
 Based on observations and experimentally
determined estimates of nutrient intakes by
healthy people
 Used when the RDA is not yet established:
calcium, vitamin D, vitamin K, fluoride
Determining Nutrient Needs
Tolerable Upper Intake Level (UL)
 Highest
average daily intake level likely to pose
no risk of adverse health effects to most people
 Consumption of a nutrient at levels above the
UL, the potential for toxic effects and health
risks increases
Determining Nutrient Needs
Vitamin C (adult age 19-70)
Example
Nutrient
DRI
UL = 2,000 mg/d
RDA = 75 mg/d (female)
90 mg/d (male)
EAR = 60 mg/d (female)
75 mg/d (male)
Amount needed to prevent
Deficiency = ~10 mg/d
Determining Nutrient Needs
Estimated Energy Requirement (EER)
 Average
dietary energy intake (kcal) to
maintain energy balance in a healthy adult
 Based on age, gender, weight, height, level of
physical activity
Determining Nutrient Needs
Acceptable Macronutrient Distribution Ranges
(AMDR)

Describes the portion of the energy intake that should
come from each macronutrient
 Carbohydrates: 45-65%
 Fats: 20-35%
 Proteins: 10-35%
Potential for
increased chronic
disease risk if
nutrient intake falls
above this range
AMDR
Potential for
inadequate nutrient
levels if nutrient
intake falls below
this range
Malnutrition
Nutritional status is out of balance: Individual is
getting too much or too little of a particular nutrient or
energy over a significant period of time
Undernutrition: too little energy or too few nutrients,
causing weight loss or a nutrient deficiency disease
Overnutrition: too much energy or too much of a
given nutrient over time, causing obesity, heart disease,
or nutrient toxicity
Assessing Nutritional Status – A,B,C,D’s
A – Anthropometric Data
♦
Weight, Height, Muscle Mass, Fat Mass
B – Biochemical Data
♦
Cholesterol, Glucose, Albumin, Sodium, Liver
Enzymes, Kidney Enzymes
C- Clinical Data
♦
Disease history, Socioeconomic Status, Physical Exam
D – Dietary Data
♦
Nutrient intake, supplement use
Dietary Intake Tools
Dietary Intake Tools
24-Hour Recall
Diet History
Food Frequency
Questionnaire
Diet Records
Twenty-four Hour Recall
Recalls all food and beverages consumed in the previous
24-hour period
Accurate recall includes serving sizes, food preparation
methods, and brand names of convenience foods or fast
foods
Limitations:

may not be typical intake
 rely on memory
 ability to estimate portion sizes
Diet History
Information from interview or questionnaire:

Weight (current and usual weight, goals)
 Factors affecting appetite and food intake
 Typical eating pattern (time, place, dietary restrictions,
frequency of eating out, etc.)
 Disordered eating behaviors (if any)
 Education and economic status
 Living, cooking/food purchasing arrangements
 Medication and dietary supplements
 Physical activity
Food Frequency Questionnaires
Determine typical dietary pattern over a predefined
period of time
Include lists of foods with the number of times these
foods are eaten
Some assess only qualitative information (typical foods
without amounts)
Semiquantitative questionnaires assess specific foods
and quantity consumed
Diet Records
List of all foods and beverages consumed over a specific
time period (3-7 days)
Kept by person seeking nutritional advice
More accurate with:


foods are weighted or measured
labels of convenience foods and supplements
People may change food intake to simplify record
keeping
Analyses are time consuming and costly
Nutrition Deficiencies
Primary deficiency occurs when a person does not
consume enough of a nutrient, a direct consequence of
inadequate intake
Secondary deficiency occurs when…
a
person cannot absorb enough of a nutrient in
his or her body
 too much nutrient is excreted from the body
 a nutrient is not utilized efficiently by the body
Primary or Secondary Deficiency?
Jane and John were both told by their primary care physicians that
they had a type of anemia called “pernicious anemia” which is
caused by a deficiency of vitamin B12 in the body. What type of
deficiency do Jane and John have based on the evidence below?
Jane is a strict vegetarian and
does not consume any
animal-based foods and does
not consume a
vitamin/mineral supplements.
John consumes a regular diet
consisting of all major food
groups but has a condition
called “gastritis” preventing
his production of intrinsic
factor, which is needed to
help absorb vitamin B12
Deficiency Symptoms
Subclinical deficiency occurs in the early stages,
few or no symptoms are observed
Covert symptoms
are hidden and require laboratory
tests or other invasive procedures to detect
Symptoms
of nutrition deficiency that become
obvious are referred to as overt
Nutrition Deficiencies
What happens in the body:
Which assessment
method reveals changes:
Physical deficiency caused by
inadequate diet OR secondary
deficiency caused by problem inside
the body
Diet history
Health history
Declining nutrient stores
Laboratory tests
Abnormal functions inside the body
Laboratory test
Physical (outward) signs and
symptoms
Physical examination and
anthropometric measures
Registered Dietitians (RD)
Requirements:



Bachelor’s degree in nutrition
Completion of supervised clinical experience
Passing a national registration examination
Work in a variety of settings:

Hospitals, clinics, nursing homes
 Sports nutrition
 Food-service management
 Community and public health nutrition
 Nutrition research
Nutrition Advice:
Who Can You Trust?
Nutrition is a new science
Increased interest in nutrition
Overwhelming amount of health claims
Reliability of nutrition information
Misinformation
Potential harmful quackery
Trustworthy Nutrition Experts
Registered Dietitian (RD)
Licensed Dietitian meets the credentialing
requirements of a given state
Nutritionist has no legal definition
Professional with advanced nutrition degree
(masters-MS, MA; doctoral-PhD)
Physician
Government Information Sources
Centers for Disease Control and Prevention
(CDC)
National Health and Nutrition Examination
Survey (NHANES)
Behavioral Risk Factor-Surveillance System
(BRFSS)
National Institutes of Health (NIH)
Reliable Nutrition Information
American Dietetic Association
American Society for Nutrition Sciences
American Society for Clinical Nutrition
Society for Nutrition Education
American College of Sports Medicine
North American Association for the Study of
Obesity
Evaluating Research
•
Case Control Studies
•
Clinical Trials
•
Randomized
• Single Blind
• Double Blind
• Placebo
Evaluating Media Reports
•
Questions to ask?
•
•
•
•
•
•
Who conducted/paid for the research?
Who is reporting the information?
Is it based on reputable research studies?
Is the report based on testimonials?
Are the claims too good to be true?
Is someone profiting?
Activity
Calculate the Nutrition
Fat = 18 grams
Carbs = 6 grams
Protein = 7 grams
Total Calories: _________
____% Fat _____ % Carbs ______% Protein
Calculate the Nutrition
Fat = 18 grams
Carbs = 6 grams
Protein = 7 grams
Total Calories: 214
76% Fat
11% Carbs
13% Protein
Calculate the Nutrition
Fat = 8.4 grams
Carbs = 23.4 grams
Protein = 4.2 grams
Fat = 2 grams
Carbs = 0 grams
Protein = 28 grams
Calculate the combined calories, protein, fat, carbs
and the percentage.
Calculate the Nutrition
Fat = 10.4 grams (93.6 calories)
Carbs = 23.4 grams (93.6 calories)
Protein = 32.2 grams (128.8 calories)
Total Calories: 316
~30% Fat
~30% Carbs
~40% Protein
Calculate the Nutrition
Total Calories: 680
Fat: ______
Carbs: 71 grams
Protein: 44 grams
Calculate the Nutrition
Total Calories: 680
Fat: 24 grams
Carbs: 71 grams
Protein: 44 grams
Calculate the Nutrition
The doctor has recommended his patient eat a
1600 calorie diet that is 50% carbs, 25%
protein and 25% fat.
How many grams and calories will the patient be
eating from each of the three macronutrients?
Calculate the Nutrition
Answer:
Calories: 1600
Carbs: 200 grams (800 calories)
Protein: 100 grams (400 calories)
Fat: 44 grams (400 calories)
Evaluating Research
Health Benefits of Chocolate
A Look at Goji Juice – Scam or Super Fruit
High Fructose Corn Syrup