Download Chapter 9

Spencer A. Rathus
Jeffrey S. Nevid
Chapter 9
Nutrition for Life
Vicki L Boye, PhD • Concordia University – Nebraska
Chapter 9
Nutrition for Life
Learning Outcomes:
 Describe tips for eating right based
on the Dietary Guidelines for America
 Describe the functions and sources
of protein
 Describe the functions, types, and
sources of carbohydrates
 Describe the functions of fats and health implications of excess fat intake
 Describe the functions of vitamins and how to obtain them
 Describe the functions of minerals and how to obtain them
 Describe the nutritional roles of water and electrolytes and the risks of
excess sodium intake
Eat to Live – Don’t Live to Eat
Nutrients
Essential – body cannot produce, required for
proper function and structure of the body and
ultimately survival
Six classifications of nutrients
proteins, carbohydrates, fats - energy supplying
vitamins, minerals, and water
Proteins (4 cal/gr) 10-15% of diet
• Basic building blocks of body tissues
muscle, bone, hair, blood, fingernails, antibodies,
enzymes, hormones
• Composed of 22 amino acids
•
9 essential amino acids: must be obtained from food
or dietary supplements
• Sources
•
Complete proteins: animal sources (meat & dairy)
•
Incomplete proteins (lacking 1+ essential amino acid)
• Need variety
• Excess protein stored as fat
Carbohydrates (4 cal/gr) 55-70% of diet
• Provide body with its major and first energy source
• Types:
 Simple carbohydrates (sugars) (1/4 of total carbs)


“Empty calories” – lacks nutrient density
#1 source of excess sugar – Pop/Soda
 Complex (starches) nutrient dense, steady flow of
energy, found in vegetables, cereals and grains

Dietary fiber – helps with digestion, lowers risk of
colorectal cancer, cardiovascular disease, diabetes
 Recommended 20-35 grams a day
 Sources: whole grains, fruits, vegetables,
legumes
Fats (9 calories per gram)
20-35% of diet
 Essential roles in the body: nourish skin, aid in
absorption of certain vitamins, help in formation of
cell membranes and hormones, provide stamina,
insulate the body
 Most concentrated source of energy - Most
Americans consume excessive amount
 contributes to obesity, heart disease, certain types of
cancer
Types of Fat
• Saturated Fats – animal and tropical oils
• Greater risk of raising blood cholesterol levels (LDL)
• Increases risk of cardiovascular disease/cancer
• Should comprise 10% or less of diet
• Unsaturated Fats – plant sources
Polyunsaturated – soybean, corn, safflower, sunflower
• Lowers total cholesterol and LDL, but may also
lower HDL
Monounsaturated – olive, canola, avocado, peanut
• Lowers total cholesterol and LDL
Trans-fats - produced by hydrogenating vegetable oils
• raises blood cholesterol as much as saturated fats
Cholesterol
A natural fat-like substance in the body cells of humans
and animals that is used to produce hormones and cell
membranes.
• Body produces all we need – body converts dietary
cholesterol into blood cholesterol, excess can result in
formation of fatty deposits in artery walls
LDL “bad cholesterol” is what allows build-up
HDL “good cholesterol” clears away deposits, sending
them to the liver will they are processed and excreted
from the body
• Limit dietary cholesterol, trans fat, saturated fat – choose
a healthier alternative
Cholesterol
Vitamins
Organic substances needed in minute amounts to
serve vital roles in metabolism, growth, and
maintenance of bodily processes
Fat-soluble vitamins: A,D,E,K
•
Carried by fats we eat, stored in liver and fatty
tissues until needed – excess can lead to toxicity
Water-soluble vitamins: B Complex, C
•
Travel freely in bloodstream, not stored, excess is
excreted in urine and sweat
You can get all the vitamins you need from a
balanced diet – food is better than supplements
Health Benefits of Vitamins
• Prevents vitamin deficiency syndromes (rare in U.S.)
• Reduce health risks
• Vitamin D – osteoporosis
• Vitamin B6 – relieves symptoms of PMS, asthma,
enhances immune system
• Folic Acid – prevention of neural tube defects
• Antioxidants
• prevent or inhibit oxidation reducing the build-up of free
radicals – linked to cancer and age-related disease such
as cataracts, heart disease, stroke
• Vitamin C, Vitamin E, and Beta-carotene
• Phytochemicals and flavonoids
Minerals
Inorganic compounds obtained from food that assist
in the formation of bones and teeth, transmission of
nerve signals, and the manufacture of hemoglobin
Consume from foods – absorbed by the body easier
Key Minerals: Health risks with too little or too much
Calcium – bone health, prevention of osteoporosis
• Build-up bone density now
Iron – forms part of the make-up of hemoglobin
• Deficiencies can lead to anemia, weakness,
reduced physical performance, immunological
functioning - women at higher risk
Water and Electrolytes
Water – most important nutrient
• transports nutrients, removing wastes through the blood,
regulating body temperature
• water depletion can lead to heat exhaustion, heatstroke
Electrolyte: conducts electricity
sodium, potassium, chloride – principle ones
Sodium:
• attracts water into blood vessels, helps maintain
normal blood volume and blood pressure
• excess intake increases blood pressure
• less than 1 tsp. of salt (added or in processed food)
a day recommended