chapter 9 book notes Flashcards
1
Q
How much water does the adults body weight constitute?
A
-60%
-& it is higher in a childs body weight
2
Q
How much water in lean tissue? How much water in fat?
A
-lean=75%
-fat=25%
3
Q
What influences how much a person body weight is water?
A
-body composition
4
Q
Proportion of water is generally smaller in who?
A
-Females, people with obesity, and older adults because of their smaller proportion of lean tissue.
5
Q
Functions of water in body fluids (7):
A
-carries nutrients & waste products throughout body
-maintains the structure of large molecules such as proteins and glycogen
-participates in metabolic reactions
-serves as the solvent for minerals, vitamins, amino acids, glucose, and other molecules
-maintains blood volume
-aids in regulation of body temp.
-acts as lubricant and cushion around joints and inside eyes, spinal cord, and amniotic sac surrounding fetus
6
Q
Water balance
A
-balance between water intake and water excretion that keeps the body’s water content constant.
7
Q
Imbalances of water can lead to:
A
-dehydration
-water intoxication
8
Q
Mild dehydration (loss of less than 5% of body weight) symptoms:
A
-thirst
-sudden weight loss
-rough, dry skin
-dry mouth, throat
9
Q
Severe dehydration (loss of more than 5% of body weight) symptoms:
A
-pale skin
-bluish lips and fingertips
-confusion
-rapid shallow breathing
10
Q
In healthy people, what governs water intake?
A
-thirst and satiety
11
Q
When blood becomes too concentrated( having lost water but not salt and other dissolved substances), what happens to the body?
A
-the mouth becomes dry
-the brain center (hypothalamus) initiates drinking behavior
12
Q
With aging what diminishes?
A
-thirst sensations
13
Q
Water intoxication
A
-rare
-excessive water consumption
-kidney disorders that reduce urine production
14
Q
Symptoms of water intoxication:
A
-severe headaches
-confusion
-convulsions
-and even death in extreme cases
15
Q
What does excessive water ingestion (several gallons) within a few hours do the the blood?
A
-dilutes sodium concentration of the blood and contributes to dangerous condition (hyponatremia)
16
Q
What two organs regulate water excretion?
A
-the brain and kidneys
17
Q
The brain & its role in regulation of water excretion when blood is high in sodium, or bp and blood volume is low:
A
-cells in brains hypothalamus, which monitor blood salts, stimulate the pituitary gland to release antidiuretic hormone (ADH). whenever salts are too concentrated.
-ADH stimulates the kidneys to reabsorb water rather than excrete it.
18
Q
The more water you need…
A
-the less you excrete.
19
Q
The kidneys and their role in water excretion regulation:
A
-cells in kidneys respond to low bp by releasing renin. (through complex events of hormone aldosterone).
-this enzyme causes the kidneys to retain more water.
20
Q
On average a person loses how much water daily?
A
-2.5 liters
21
Q
The more a person drinks, the more ? their urine becomes:
A
-dilute
22
Q
Besides urine, how else is water lost?
A
-from lungs as vapor
-some excreted in feces
-and some evaporates from the skin
23
Q
Water needs depend on these factors:
A
-environmental temp. & humidity
-activity level
-what a person eats
24
Q
In the past how was water intake expressed?
A
-in proportion to the amount of energy expended under normal environmental conditions
EX: person expends 2000kcal a day, meaning they are to drink 2-3 liters of water (8-12 cups).
25
DRI adequate intake (AI) for total water for men & women:
-men=3.7
-women=2.7
26
What kind of urine reflects appropriate dilution?
-pale, yellow
27
How much water does veggies and fruits have? What about in meats and cheeses?
-95%
-50%
28
DRI insight on caffeinated drinks and water intake:
"caffeinated beverages contribute to the daily total water intake similar to that contributed by non-caffeinated beverages"
29
Electrolytes
-a salt that dissolves in water and dissociates into charged particles called ions
30
Body fluids contain:
-water and partly dissociated salts
-AKA electrolyte solutions
31
Bodys electrolytes are..:
-vital to life of cells
-must be closely regulated to help maintain appropriate distribution of body fluids
32
major minerals form salts that dissolve in the body fluid;
-the cells direct where these salts go
-movement of salts determines where the fluids flow because water follows salt
33
Cells use what force to move fluids back and forth across their membranes:
-Osmosis
-movement of water across membrane toward the side where concentration of dissolved particles is greater.
34
Protein pumps & concentration of potassium, sodium, and chloride inside cells:
-sodium and chloride are concentrated outside of cell
-potassium is concentrated inside cell
35
The kidneys filter what out of the blood?
-sodium, then they return to the bloodstream the exact amount the body needs to retain.
36
Sudden loss of fluid and electrolyte requires...
-medical intervention
-severe stresses include vomiting, diarrhea, heavy sweating, fever, burns, and wounds.
37
Electrolytes and acid-base balance:
-act as buffers (substances that accommodate excess acids or bases)
38
what organ plays the primary role in maintaining acid-base balance?
-the kidneys
39
Major minerals:
-essential mineral nutrients required in the adult diet in amounts greater than 100 milligrams per day.
40
What are the major minerals? (7)
-calcium
-chloride
-magnesium
-phosphorus
-potassium
-sodium
-sulfur
41
Trace minerals:
essential mineral
nutrients required in the adult diet
in amounts less than 100 milligrams
per day.
42
What are the trace minerals (9)
-chromium
-copper
-fluoride
-iodine
-iron
-manganese
-molybdenum
-selenium
-zinc
43
Difference between trace and major minerals?
- major minerals are named so because they are present, and needed, in
larger amounts in the body than the trace minerals.
-NOT BECAUSE THEY ARE MORE IMPORTANT
44
Which two minerals are not eaten enough and are linked to chronic diseases?
-calcium & potassium
45
What mineral is overconsumed?
-sodium
46
Which minerals are most noted for their role in the body's fluid balance?
-sodium. chloride, and potassium
47
Which minerals are critical for nerve transmission & muscle contractions?
-sodium
-potassium
-calcium
-magnesium
48
Minerals involved in energy metabolism?
-phosphorous and magnesium
49
Minerals that contribute to structure of bones:
-calcium, phosphorus and magnesium
50
Which mineral helps determine shape of proteins?
-sulfur
51
Sodium:
-principle electrolyte in the extracellular fluid (fluid outside cells)
-primary regulator of extracellular fluid volume
-helps maintain acid-base balance and muscle contraction and nerve transmission
52
When blood concentration of sodium rises, as a person eats salty foods:
-thirst prompts the person to drink water until sodium-water ratio is restored.
53
Too much sodium can lead to
-high blood pressure (hypertension)
54
Average US sodium intake is:
3400 milligrams per day
55
Chronic disease risk reduction intake for adults is set at ? to prevent high blood pressure:
-2300 milligrams per day
=1 teaspoon of salt
56
What % of the US adult population meets or exceeds this amount daily?
-90%
57
Top food contributors of sodium in diet:
-breads and rolls
-cold cut and cured meats
-pizza
-chicken
-soups
58
Which organ system regulates sodium in the body?
-gastrointestinal
59
Nearly what % of US adults have hypertension? What race is the highest?
-50%
-with african americans adults the highest in the world at 54%
60
DASH (Dietary Approaches to Stop Hypertension):
-dietary pattern proven to help people reduce sodium and increase potassium intake to reduce blood pressure
61
DASH food choices:
potassium-rich fruits and vegetables and fat-free or low-fat dairy products;
includes whole grains, nuts, poultry, and fish
62
Chlroide
-major negative ion of the extracellular fluids, where it occurs primarily in association with sodium
-critical in maintaining fluid, electrolyte, and acid-base balances in body.
63
Chloride in the stomach:
-the chloride ion is part of
hydrochloric acid, which maintains the strong acidity
64
Salt & chloride:
-Salt is a major food source of chloride, and, as with sodium, processed foods are a
major contributor of this mineral to people’s diets.
65
Which mineral is high in weight in salt? SODIUM OR CHLORIDE?
-chloride
-chloride recommended intakes are higher than sodium
66
Potassium functions:
-produces proteins
-maintenance of fluid-electrolyte balance
-supports cells integrity
-transmission of nerve pulses and muscles contraction (including heart)
67
During nerve impulse what happens with potassium and sodium?
-During nerve impulse transmission and muscle contraction, potassium and sodium trade places briefly across. the cell membrane.
-The cell then quickly pumps them back into place.
68
Excess potassium loss through severe diarrhea can cause:
-heart failure
69
Potassium deficiency usually happens due to:
-excessive lost rather than not enough being taken in
-diuretics
70
Severe potassium deficiency:
-cardiac arrhythmias, muscle weakness, and glucose intolerance.
71
Potassium toxicity:
-results from overconsumption of potassium salts or supplements, certain disease or medications.
72
Potassium toxicity symptoms:
-muscular weakness
-vomiting
-if given directly in vein, can stop the heart.
73
Potassium food sources
-fruits, vegetables, meats, milk
-BANANAS
74
Potassium and hypertension
-regular intake of potassium helps maintain a normal BP thus reducing risk of hypertension, heart disease, and stroke.
75
Calcium:
-develops a healthy skeleton and prevents bone disease
-most abundant mineral in body (99% is stored in bones and teeth).
76
2 roles calcium plays in bones:
-integral part of bone structure
-serves as calcium bank available to body fluids should a drop in blood calcium occur.
77
Active growth phase of bone:
-from birth to age 20
-bones are actively growing by modifying length, width, and shape.
78
Peak bone mass development:
-ages 12-30
-skeletal mass increases
-bones grow thicker and denser
79
Bone loss development:
-30 to 40 years of age and continues throughout remainder of life
-bone loss exceeds new bone formation.
80
When blood calcium is too high:
-a system of hormones,
including vitamin D, promotes its deposition into bone.
81
When blood calcium falls too low, 3 locations in the body act to rise it:
1)small intestine absorbs more calcium
2)bones release more calcium into blood
3)kidneys excrete less calcium
82
A deficiency of calcium only affects:
-the bones not the calcium in blood
83
Calcium deficiency symptoms:
-stunted growth in children
-osteoporosis (adult bone loss)
84
In the US about ? of all adults 50 years or older develop osteoporosis:
-1/4
-most are women, due to be smaller, consume less calcium, and menopause causes 20% bone loss
85
? million of people break a hip, leg, hand, etc. due to osteoporosis:
-2 million
86
How much calcium does each person absorb?
Infants & children=
Adults=
Pregnant women=
-60%
-20-30%
-50%
87
Calcium in foods:
-dairy products (most abundant)
-oysters
-tofu
88
Phosphorus function:
SECOND MOST IMPORTANT MINERAL IN BODY
-mineralization of bones & teeth
-cell's genetic material
-phospholipids
-energy transfer
-buffer system
89
phosphorus deficiency:
NONE
90
Phosphorus is part of what in genetic material?
DNA & RNA
91
Phosphorus foods:
animal sources (meat, fish, eggs, milk)
92
Magnesium function:
-bone mineralization
-production of proteins
-enzyme action
-nerve impulses
93
how much magnesium is present in a 130lb person?
1 ounce, more than half in bones
94
Magnesium and calcium in muscle action:
-work together for proper functioning of the muscles: calcium promotes contraction, and
magnesium helps relax the muscles afterward.
95
Magnesium deficiency:
-low blood calcium
-cramps, confusion
-seizures, hallucinations
96
magnesium food sources:
-nuts, legumes, whole grains, chocolate, seafood
97
Sulfate is the oxidized form of
-sulfur
98
Sulfate functions:
-shape proteins
-component of amino acids biotin & thiamin and insulin
99
Sulfate deficiency:
-NONE
100
Sulfate foods:
-all protein containing foods
101
IF all trace minerals were removed from body..
-you would only have a bit a dust, hardly enough to fill a teaspoon.
102
Iron function:
-hemoglobin
-myoglobin
-utilizes energy
103
Protein hemoglobin
-in red blood cells
-iron in hemoglobin helps carry oxygen from lungs to tissues throughout the body.
104
Protein myoglobin:
-hold oxygen for muscles to use when they contract
105
When a red blood cell dies...
-the liver saves the iron and returns it to bone marrow, which uses it to build new red blood cells.
106
The body loses iron from..
-tiny amounts:
-digestive tract
-nail and hair trimmings
-shed skin cells
-BLEEDING=EXCESSIVE LOST IN IRON
107
Iron is a powerful:
-oxidant that increases oxidative stress and inflammation that can damage body tissues.
-SO NEEDS TO BE MAINTAINED
108
Because the body does not excrete excess iron..
-regulation of adsorption plays a critical role in iron homeostasis.
109
How much of dietary iron is absorbed?
10-15%
110
Transferrin
-a special protein in intestinal cells captures iron and holds it in reserve for release into body as needed.
-carries iron in blood to tissues around body
-more iron =more transferrin
111
Additional iron storage proteins:
-ferritin
-hemosiderin
112
hepcidin
-a hormone secreted by the liver in response to elevated blood iron.
-Hepcidin reduces iron’s absorption from
the intestine and its release from
storage.
113
What is the most common nutrient deficiency?
-iron deficiency; small, pale red blood cells
114
Iron intake is especially important to
-women in their reproductive years
-pregnant women
-infants & toddlers
-adolescents
115
Causes of iron deficiency:
- intake of iron-poor food choices
-lack of food
116
3 stages of iron deficiency:
1) iron stores and ferritin levels diminish
2)decrease in transport iron
3)lack of iron limits hemoglobin production
117
most common tests used to evaluate iron status:
-hemoglobin and hematocrit tests
118
Iron deficiency and iron deficiency anemia are:
-not the same thing
-some people may be iron deficient without being anemic
119
Iron deficiency
refers to depleted body iron stores without regard to the degree of depletion or to the
presence of anemia.
120
iron deficiency anemia
refers to the severe depletion of
iron stores that results in a low hemoglobin concentration
-cant carry enough oxygen from lungs to tissues
121
people with anemia only feel fatigue when they..
-exert themselves
122
iron defiency symptoms:
-weakness, pallor, headaches, inability to concentrate, lower cold tolerance
-impaired cognitive function (children)
123
Pica
-curious behavior in some iron deficient people
-craving for and consumption of ice, chalk, clay.
124
Iron toxicity:
-iron overload
125
Most likely cause of iron overload:
-disorder known as hemochromatosis: genetic failure to prevent unneeded iron in the diet from being absorbed.
126
Symptoms of iron overload
-similar to those if iron deficiency
-infections, liver injury, bloody stools
127
Iron poisoning
-rapid ingestion of massive amounts of iron can cause death
-as few as 5 iron tablets have caused death in a child
128
Iron occurs in two forms of food:
-heme (10x more absorbable and bound to hemoglobin and myoglobin in meat fish and poultry)
-nonheme (absorbed at a lower rate and found in meats and plants
129
Iron absorption can be maximized by two substances:
-MFP factor
-Vitamin C
130
cooking in a iron skillet can
add iron to the diet
131
Zinc function
-part of insulin & enzymes
-makes genetic material
-transports vitamin A
-taste/smell
-sperm production & fetal development
132
Zincs main transport vehicle: in blood:
-protein albumin
133
When was zinc deficiency first reported?
-1960s
-children and males in egypt, turkey, and iran
-dwarfism and severe growth restriction
134
Zinc deficiency symptoms:
-delayed growth
-delayed sexual maturation
-loss of taste
-poor wound healing
135
Zinc foods:
-protein containing foods (meat, fish shellfish)
136
selenium function:
-assists groups of enzymes that break down reactive chemicals that harm cells.
-ANTIOXIDANT NUTRIENT
137
Selenium deficiency:
-Keshan disease (heart disease in children and women in China where soil and foods lack selenium)
138
Iodine function
-component of two thyroid hormones which regulate body temp, reproduction, growth, etc.
139
iodine defciency:
-goiter, cretinism
140
Goiter
-earliest and most obvious sign
-enlargement of thyroid gland due to the cells wanting to trap iodide.
-become sluggish and gain weight
141
Cretinism
-severe iodine deficiency during pregnacy
-causes extreme and irreversible intellectual disabilities and physical stunting.
142
What is the worlds major source of iodine?
-the ocean
143
Iodine food sources:
-iodized salt
-seafood
-bread
144
copper function:
-necessary for absorption and use of iron in formation of hemoglobin
-part of several enzymes
145
body contains about ? milligrams of copper:
-100
-1/4 is in muscles
-1/4 is in liver, brain and blood
146
copper deficency
-RARE
-anemia, bone abnormalities
147
Consuming too much of what mineral will block coppers absorption?
Zinc
148
Fluoride function:
-element involved in formation of bones and teeth
-prevents dental carries
149
fluoride deficiency:
-dental problems/carries
150
fluoride toxicity:
fluorosis (pitting and discoloration of teeth)
151
Fluoride food:
-drinking water (if fluoride containing)
-tea
-seafood
152
chromium function:
-carb and lipid metabolism
-enhances activity of insulin and improves glucose tolerance
153
chromium deficiency:
-diabetes like condition
154
chromium foods:
-meats, whole grains
