General Nutrition
Kathaleen Briggs Early, PhD, RD, CDE
Assistant Professor and Registered
Dietitian
kearly@pnwu.org
Learning Objectives
o Upon completion of this module, the student will
be able to:
1. Define “macronutrients” and identify what the
food sources are for the macronutrients
2. Define “micronutrients” and identify what the
food sources are for the major micronutrients
3. Identify the components of a healthy diet
4. Identify patients at nutrition risk
5. Identify the causes of malnutrition and those
who are malnourished
6. Explain the benefits of breastfeeding during
infancy
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Definitions
o A nutrient is any substance in food that
the body can use to
– obtain energy,
– synthesize tissues, or
– regulate body processes
o Macronutrients
– Carbohydrates
– Proteins
– Lipids
o Micronutrients
– Vitamins
– Minerals
o Water
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Macronutrients: CARBOHYDRATES
o Primary source of calories (energy) and glucose (4 kcal/gm)
– Glucose is the body’s preferred fuel source
– Most people get about half of all their calories from
carbohydrates
o Food sources
– Breads, grains, cereals, rice and pastas are the biggest sources
– Dairy/non-dairy alternatives (milk, yogurt, soy and rice milk)
– Fruits in any form (fresh, frozen, juice, canned, dehydrated)
– Vegetables also have some carbohydrates
• Common vegetable-based carbs in Western diet are Peas, Corn and
Potatoes
– Sweets
• Cakes, cookies, ice cream, pastries, etc.
o No carbohydrates in meats or cheeses
o Carbohydrate-rich foods are also an important source of fiber and
antioxidants
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Macronutrients: FATS
o Essential for health
– Cellular membrane structure and function
– Myelin sheath in nervous system
– Fat tissue keeps us warm, provides some
protection to our organs
o Concentrated source of calories (9 kcal/gm)
– Saturated dietary fats
• Animal-based
– butter, lard, whole and 2% milk, meat, skin
• Plant-based
– coconut and coconut oil, palm kernel oil, palm oil,
cocoa butter
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Macronutrients: FATS
– Unsaturated dietary fat
• Monounsaturated fatty acids (MUFA)
– Olive and canola oils
• Polyunsaturated fatty acids (PUFA)
– Corn, safflower, sunflower, fish oils
– Trans fats
• Very small amount of trans fats are naturally occurring
in dairy foods, meat, and darker-meat poultry
– Cholesterol from the diet
• Only found in animal-based foods
• Whole fat dairy products, egg yolks, meat, poultry
skin and dark poultry meat
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Macronutrients: PROTEINS
o Primary role is to maintain structural and
functional integrity
– Muscle tissue, skin, bone, organs, enzymes,
hormones, neurotransmitters, fluid and acidbase balance, cellular transport, and blood
clotting
o Proteins are made up of amino acids
o Some amino acids are essential, others are nonessential, and still others are “conditionally”
essentially
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Macronutrients: PROTEINS in
Vegetarian Diets
o Vegetarian diets can be a very healthy option
o Complete vs. Incomplete
– Complete proteins contain all 9 essential amino
acids (e.g., milk, egg, chicken, meat, fish)
– Soy is the only plant-based complete protein
– Incomplete proteins are lacking in 1 or more
essential amino acids
– It is not necessary to combine incomplete
proteins at a meal
• More important to eat a variety of foods consumed
throughout the day to provide the most diverse amino
acid and protein sources
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Micronutrients: Vitamins
Water-soluble
o Not stored in the body
o Deficiencies may develop
quickly if inadequate
intake occurs
– B vitamins
•
•
•
•
•
Folic acid (folate)
B12 (cobalamin)
Thiamin (B1)
Riboflavin (B2)
Niacin (B3)
Fat-soluble
o Stored in liver and fat
tissue for long periods of
time
o Deficiencies develop very
slowly
–
–
–
–
Vitamin A
Vitamin D
Vitamin E
Vitamin K
– Vitamin C
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Micronutrients: Major Minerals and
their Common Food Sources
o Calcium
• dairy products, dark leafy green vegetables, tofu
o Phosphorus
• Animal proteins, dairy foods, legumes; wide-spread in
food supply
o Magnesium
• Whole grains, “hard” water
o Sodium
• Processed foods, preserved foods, added salt in
cooking and at the table
o Potassium
• Fruits and vegetables
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Micronutrients: Trace Minerals and
their Common Food Sources
o Copper
• Liver, shellfish, lentils, mushrooms, cashews, sunflower
seeds
o Iodine
• Iodized salt, seafood
o Iron
• Most well absorbed: Beef, dark poultry meat, whole eggs,
tuna, salmon, legumes, iron fortified cereals, liver
• Less well absorbed: prunes, raisins, apricots, dark leafy
green vegetables, brown rice
o Selenium
• Brazil nuts, tuna, beef, brown rice
o Zinc
• Oysters, meat, poultry, legumes, shellfish, whole grains
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Micronutrient (vitamin) Deficiency
o Pellagra (Niacin deficiency)
• The 4 D’s: diarrhea, dermatitis, dementia and
death
o Pernicious Anemia (B12 deficiency)
• Caused from autoimmune destruction for stomach
cells needed for intrinsic factor production
o Vitamin A deficiency
• Leading cause of preventable blindness in
children
• Increases the risk of disease and death from
severe infections
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Micronutrient (vitamin) Deficiency
o Scurvy (vitamin C deficiency)
• Collagen breakdown resulting in bleeding gums
and petechiae
o Rickets and Osteomalacia (vitamin D
deficiency)
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Micronutrient (mineral) Deficiency
o Iodine
– Regions at greatest risk include countries of the
former Soviet Union, south Asia and parts of
Africa
– Thyroid enlargement (goiter) is an early and
visible sign of iodine deficiency
o Iron
– Iron deficiency anemia
– Fatigue, rapid heart rate, and rapid breathing on
exertion are the most common signs
o Selenium
– Kashin disease
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Dietary History
o Questions the nurse can ask the patient directly
– Do you eat a wide variety of foods?
– Do you have difficulty obtaining adequate food?
– Do you have any food allergies/intolerances?
– Do you have family? Do you eat alone or with
others?
o Questions the nurse should consider in their
assessment
– Is the patient obviously under or overweight?
– Does the patient have any obvious warning signs
of nutrient deficiencies (see slides 18-27)?
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Optimizing Nutrition
o WHO’s five keys to safer food
– Keep clean
– Separate raw and cooked
– Cook thoroughly
– Keep food at safe temperatures
– Use safe water and raw materials
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Assessing Physical Activity
o With the world-wide obesity epidemic,
addressing physical activity is essential
o Use the FITT principle
– F: How many times per week does the
activity occur?
– I: How vigorous is the activity?
– T: What is the activity? What is its purpose?
– T: How many minutes of the activity are
done per session?
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Anthropometrics
o Height
• A key indicator of chronic malnutrition is stunted growth
o Weight
• Recent weight loss is a very sensitive marker of a patient’s
nutritional status
• Weight loss of more than 5% of usual body weight in 1
month or 10% in 6 months before hospitalization is clinically
significant
o Weight for height
• BMI
o Body fat assessment
o Activities of Daily Living
o Strength
– e.g., grip strength
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Physical Assessment of Nutrition Status
o Orbital fat pads
• should be present
o Triceps skinfold thickness
• 1 cm or less = malnourished
o Anterior lower ribs
• Ribs should not be visible if adequately nourished
o Temples
• should not be sunken
o Clavicle
• should not be overtly prominent
o Shoulders
• Should be rounded or sloped, not squared
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Physical Assessment of Nutrition Status
o Interosseus muscle
– Should be bulging when thumb and forefinger
pinch together
o Scapula
– When hand presses against a wall, back
should be smooth if adequately nourished
o Thigh and Calf
– Should be solid
– Loose skin upon muscle massage indicates
severe deficit
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Physical Assessment of Nutrition Status
o Edema
– In ambulatory patients, no impression should
remain following pressure application
o Ascites
– Should not be present in healthy individuals
– Degree of fluid accumulation in abdominal
cavity can be indicative of nutrition status
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Malnutrition
o When more than 20% of usual body weight is lost,
most physiologic body functions become
significantly impaired
o Malnutrition can also reduce cardiac output, impair
wound healing, and depress immune function
o Nutritional repletion can often reverse these
processes and significantly improve patient
outcomes
o Difficulty is identifying individuals at risk so that
appropriate interventions can be made
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Protein Energy Malnutrition (PEM)
o Most common form of malnutrition
o Most often seen in the western hospitalized patient
with
–
–
–
–
–
–
End-stage liver or renal disease
Cancer cachexia
HIV/AIDS wasting disease
Severe eating disorder
Neglect
Long-term recovery from multiple trauma
o Outside industrialized countries, more often seen in
areas of severe drought, infectious disease, and war
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Kwashiorkor
o “Pot Belly” appearance due to hepatic edema
and fatty liver
o Increased extracellular fluid (edema) and low
plasma albumin levels
– Increase in extracellular fluid may mask
underlying weight loss
o Rapid onset; may develop in a few weeks
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Marasmus
o Significant deficit of total body fat and body
protein with a slight increase in extracellular
water
o Obvious body wasting
– Skin and bones appearance
o Eyes may be sunken
o Skull and cheekbones may be prominent
o Plasma albumin is often in the low-normal
range
o Usually takes months or years to develop
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Comparison of the features of
kwashiorkor and marasmus
Feature
Kwashiorkor
Marasmus
Growth failure
Present
Present
Wasting
Present
Present, marked
Edema
Present (sometimes mild)
Absent
Hair changes
Common
Less common
Mental changes
Very common
Uncommon
Dermatosis, flaky-paint
Common
Does not occur
Appetite
Poor
Good
Anemia
Severe (sometimes)
Present, less severe
Subcutaneous fat
Reduced but present
Absent
Face
May be edematous
Drawn in, monkey-like
Fatty infiltration of liver
Present
Absent
FAO/WHO
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Assessing Malnutrition
o Temples (temporalis muscles)
should be visualized
for evidence of
wasting
o Dull hair, easily
plucked = protein
energy deficiency
o Brittle hair, breaks
easily suggests
micronutrient
deficiencies
http://meded.ucsd.edu/clinicalimg/head_temporal_wasting2.htm
http://meded.ucsd.edu/clinicalimg/index.htm
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Causes of Malnutrition
o Hunger
– Due to poverty and food insecurity
o Micronutrient or protein deficiency
– More common in elderly
o Disease
– Infectious disease (e.g., malaria, TB, see
next slide)
– Chronic disease (e.g., HIV AIDS, cancer,
emphysema, etc)
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Defining a Healthy Diet
o
o
o
o
o
o
o
Aids in maintaining a healthy body weight
Promotes general well-being
Satisfies hunger and appetite
Culturally and age appropriate
Suitable to personal preferences
Prevents chronic disease
Adequate in overall nutrition and balance
– High consumption of fruits & vegetables
– Low consumption of red meat & fatty foods
– Whole and fresh foods are preferred to processed or
refined foods
– Protein primarily from fish, dairy products, and/or legumes
– Limited in added salt, sugar, and alcohol
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World Health Organization’s
Five Keys to a Healthy Diet
o Give baby only breast milk for the first six
months of life
o Eat a variety of foods
o Eat plenty of vegetables and fruits
o Eat moderate amounts of fat and oils
o Eat less salt and sugars
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Benefits of Breastfeeding
For infants
o favorable balance of
nutrients
o improve cognitive
development
o protects against
infections
o protect against chronic
diseases
– Impacts gene expression
o protects against food
allergies
For mothers
o contracts the uterus
o delays return of regular
ovulation (especially in
exclusively-breastfeeding
moms)
o conserves iron stores
o protects against breast
cancer (especially premenopausal forms)
o aids in return of prepregnancy weight
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Recommendations for Breastfeeding
o World Health Organization:
– Exclusive breastfeeding for first six months
– Introducing age-appropriate and safe
complementary foods at six months
– Continuing breastfeeding for up to two years
or beyond
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Contact Information
Kathaleen Briggs Early, PhD, RD, CDE
kearly@pnwu.org
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