Lecture 7 Flashcards
1
Q
how long can you survive without water?
A
a few days
2
Q
what % of an adults body weight is water?
A
60%
3
Q
water characteristics
A
- found in blood and cells all throughout body
- participates in many chemical reactions
- delivers nutrients and removes waste from cells
4
Q
functions of water
A
- universal solvent
- body’s cleansing agent
- incompressibility
- lubricates
- role in thermoregulation
5
Q
water as a universal solvent?
A
- dissolves amino acids, glucose, minerals etc for transport
- fatty substances get packaged with water-soluble proteins for transport in blood and lymph
6
Q
water as the body’s cleansing agent
A
- nitrogen waste dissolve in blood and must be removed
- kidneys filter these wastes and mix them with water to be excreted as urine
7
Q
waters incompressibility
A
- enables it to act as a lubricant and cushion for joints
- cushions sensitive tissues (spinal cord and fetus)
- fills eye keeping optimal pressure
8
Q
water lubricate function
A
mucus moistens the digestive tract, respiratory tract, and all tissues
9
Q
waters role in thermoregulation
A
- sweat cools the body (evaporation)
- blood routed through capillaries in skin gets rid of excess heat
- cooled blood flows back to body’s core
10
Q
water balance
A
water intake needs to equal water loss
11
Q
what happens if water intake doesn’t equal water loss?
A
dehydration or water intoxication/over-hydration can occur
12
Q
dehydration progression of symptoms
A
- thirst
- weakness
- exhaustion and delirium
- death
13
Q
loss of <5% bodyweight due to dehydration symptoms
A
- headache
- fatigue
- confusion
- forgetfulness
- elevated heart rate
14
Q
what may chronic low fluid increase likelihood of?
A
- bladder and colon cancer
- heart attack
- gallstones
- kidney stones
- urinary tract infections
15
Q
water intoxication
A
very dangerous dilution of body fluids due to excessive water ingestion (gallons or more in few hours)
16
Q
symptoms of water intoxication
A
- headache
- muscular weakness
- lack of concentration
- poor memory
- loss of appetite
- convulsions and death
17
Q
body and sodium
A
- high-salt meals lead to water retention
- water is lost over a 1-2 day period as sodium is excreted
18
Q
bodys water content
A
varies by kilograms at a time
19
Q
hypothalamus
A
- major role in monitoring blood concentration
- high blood concentration (salt) or low blood pressure signals thirst
20
Q
ignoring thirst
A
leads to dehydration
- drink whenever thirsty to replace lost fluids
21
Q
older adults and thirst
A
thirst is blunted in older adults so they should drink regularly throughout the day
22
Q
prolonged vomiting or diarrhea
A
- could result in fluid and electrolyte imbalance
- life-threatening disruption of heartbeat
23
Q
how much water should females drink per day?
A
2.7 L/day
24
Q
how much water should males drink per day?
A
3.7 L/day
25
what does total water intake include?
1. caffeinated and non-caffeinated beverages
2. food
26
27
water content of foods
1. meat and cheese (50%)
2. veggies and fruit (80-95%
28
hard water
water with high calcium and magnesium
29
soft water
water with high sodium
- may aggravate hypertension and heart disease
30
what is left behind upon death?
minerals (about 2.3kg)
31
minerals
1. chemical elements
2. inorganic
3. not energy yielding
4. micronutrients
32
minerals and cooking
not destroyed by cooking or storing
- may leach into cooking water
33
bioavailability of minerals
binders such as phytates in legumes, bind with minerals decreasing their absorption
34
major minerals characteristics
1. essential nutrients
2. amounts exceed 5 grams
35
trace minerals characteristics
1. essential nutrients
2. amounts less than 5 grams
36
the major minerals
1. calcium
2. phosphorus
3. potassium
4. sulphur
5. sodium
6. chloride
7. magnesium
37
calcium
1. most abundant mineral in the body
2. 99% stored in bones and teeth
38
what is the most abundant mineral in the body?
calcium
39
calcium 2 major roles in bones
1. integral part of bone structure
2. bone serves as a calcium reserve
40
what minerals are essential to bone formation?
calcium and phosphorus
41
bone fomation
1. calcium phosphate salts crystallize on collagen, forming hydroxyapatite crystals that add rigidity to bone
2. fluoride may displace hydroxy making fluorapatite
42
fluorapatite
mineral that resits bone-dismantling
43
formation of teeth
similar to bone
- fluoride hardens and stabilizes the crystals of teeth and makes enamel resistant to decay
44
calcium concentration in blood
1. calcium conc is constant in blood
2. blood calcium is regulated by hormones (not daily intake)
45
what happens if calcium intake is inadequate?
normal blood calcium is maintained at expense of the bones
46
what happens when calcium need increases?
1. calcium absorption from intestine increases
2. loss of calcium via the kidneys is reduced
3. percent absorbed increases as dietary intake decreases (with help of vitamin D)
47
bone loss
1. by late 20s peak bone mass is reached
2. after 40 bones begin to reduce density
48
how can bone loss be slowed
1. a diet rich in calcium
2. sufficient physical activity
49
calcium-poor diet during growing years
may prevent a person from achieving peak bone mass
50
insufficient bone calcium
increases risk of osteoporosis
(bones become brittle and fragile)
51
what % of calcium is in the body fluids?
1%
52
1% of calcium in the body fluids role
1. muscle concentration and relaxation
2. nerve functioning
3. blood clotting
53
good calcium sources
1. milk and milk products
2. fortified soy beverages and other fortified milk alternatives
3. fish with bones
4. calcium set tofu
5. broccoli, some leafy greens and legumes
6. fortified juices
54
calcium deficiency adults
bone loss
55
calcium deficiency children
stunted growth and weak bones
56
calcium deficiency
1. consumption of milk has declines
2. consumption of beverages such as soft drinks increased
57
calcium toxicity symptoms
1. constipation
2. kidney stones
3. interferes with absorption of other minerals
58
milk and milk replacements
people who don't drink milk for many reasons must obtain calcium from other sources
59
children who don't drink milk
1. often have lower calcium intakes
2. often have poorer bone health than those who drink milk regularly
60
veggies good sources of calcium
1. rutabaga
2. broccoli
3. beet greens
4. collards
5. kale
61
veggies poor sources of calcium
1. spinach, swiss chard, rhubarb
- binders in some veggies inhibit calcium absorption
62
spinich
1. still good to eat
2. iron, beta-carotene and phytochemicals rich
3. poor calcium source
63
dark greens of all kinds
1. great source of riboflavin
2. indispensable for vegans or anyone else who doesn't drink milk
64
osteomalacia
vitamin D deficiency disease leads to impaired mineralization of bone
65
characteristics of osteomalacia
1. overabundance of unmineralized bone protein
2. ratio of bone mineral to matrix is low
66
symptoms of osteromalacia
1. bending of spine
2. bowing of legs
67
osteoporosis
reduction in bone mass of older persons in which the bone becomes porous and fragile
- bone mineral to matrix ratio is normal
68
are osteoporotic fractures more common in males or females?
women (1 in 3)
69
hip fractures due to osteoporosis
1. most serious - rarely clean break (into fragments)
2. requires major surgery
3. many elderly people never walk or live independently again
4. 1/5 die within a year
70
osteoporosis development
develops silently (silent thief)
- slowly decreasing bone density until many years later, hip gives away
71
high correlation risk factors for osteoporosis
1. age (advancing)
2. sex
3. heavy drinking
4. chronic steroid use
5. rheumatoid arthritis
6. underweight/weight loss
7. removal of ovaries or testes
8. genetics (fam history)
9. race
72
what race is at more at risk for osteoporosis?
white people
73
moderate correlation risk factors of osteoporosis
1. chronic thyroid hormone use
2. smoking
3. type I diabetes
4. insufficient dietary calcium and vitamin D
5. inadequate vitamin K
6. physical inactivity
7. excessive antacid use
74
black people and osteoporosis
more protective against osteoporosis
- black women have denser bones and lose density more slowly than white women
75
sex and osteoporosis
women = 2/3 cases of osteoporosis
- men have greater bone density
76
hormones and osteoporosis
1. women experience greater bone loss during menopause
2. bone loss tapers off after 6-8 years following menopause
3. men produce only little estrogen, yet they resist osteoporosis better than women
77
testosterone and osteoporosis
men experience more fractures with reduced testosterone
ex. after removal of diseased testes or decreased function with aging
78
physical activity and osteoporosis
without PA, bone lose strength
79
muscle use
promote bone strength
- active people have denser bones
80
flexibility and muscle strength
gained through physical activity also improves balance and help prevent falls from occuring
81
what to do to keep bones healthy and to prevent falls?
include weight bearing activities every day
- calisthenics, dancing, jogging, vigorous walking, weight training
82
body weight and osteoporosis
1. being underweight increases risk
2. heavier body weights and higher fatness stress the bones and promote their maintenance (but obesity may have negative effect)
83
tobacco smoke, alcohol and osteoporosis
1. smokers have less dense bones
2. people with heavy alcohol use experience more frequent fractures
84
high protein diet and osteoporosis
1. excess protein causes body to excrete calcium is urine
2. sufficient dietary protein is essential to bone health
85
sodium and osteoporosis
1. high sodium intake associated with urinary calcium excretion
2. lowering sodium intakes seems to lessen calcium loss
86
diet to lower sodium and increase potassium intake
1. rich in unprocessed foods (fruits and veggies)
2. restricted in highly processed, convenience, or fast foods
87
caffeine and osteoporosis
link between heavy consumption of caffeine and osteoporosis
88
89
soft drinks and osteoporosis
high conc of fructose from pop or phosphoric acid may cause calcium loss
- displace milk from diet
90
vitamin K and osteoporosis
plays important roles in production of at least one bone protein (osteocalcin) that participates in bone maintenance
- people with hip fractures often have low vitamin K
91
magnesium and bones
helps maintain bone density
92
vitamin A and osteoporosis
1. needed in bone-remodeling process
2. too much may be associated with osteoporosis
93
what is the second most abundant mineral in the body?
phosphorus
94
where is the majority of phosphorus found?
bones and teeth
95
phosphorus function
1. helps maintain acid-base balance (buffers)
2. part of DNA and RNA
3. part of molecules of phospholipids
4. metabolism of energy yielding nutrients
5. assist many enzymes and vitamins in extracting energy
96
phosphorus needs
easily met by almost any diet
97
phosphorus toxicity
calcification of soft tissues
98
phosphorus sources
1. animal proteins are best sources
2. cola drinks
99
where is magnesium stored
1. half of body's magnesium in bones
2. remainder in muscles, heart, liver and other soft tissues
3. only 1% in body fluids
100
how do you maintain concentration of magnesium in the blood?
1. magnesium can be taken from bones
2. kidneys can act to conserve magnesium
101
magnesium functions
1. assists in functioning of more than 300 enzymes
2. release and use of energy from energy-yielding nutrients
3. works with calcium for functioning of muscles
102
calcium and magnesium relationship
1. calcium promotes contraction
2. magnesium helps muscles relax afterwards
3. magnesium is involved in bone mineralization and promotes resistance to tooth decay by holding calcium in tooth enamel
103
sources of magnesium
1. nuts and legumes
2. whole grains
3. dark green veggies
4. seafood
5. chocolate
- easily washed and peeling away from foods during processing
104
best source of magnesium
unprocessed foods
- most canadians reach EAR but not RDA
105
what may a magnesium deficiency occur as a result of?
1. inadequate intake
2. vomiting
3. diarrhea
4. alcoholism
5. protein energy undernutrition
106
magnesium deficiency symptoms
1. muscle weakness
2. could relate to CVD, heart attack, high blood pressure
107
magnesium toxicity
1. rare but can be fatal
2. only occurs with high intakes from non-food sources such as supplements or magnesium salts
108
magnesium laxatives and antacids
can cause diarrhea and acid-base imbalance
109
sodium function
1. fluid and electrolyte balance
2. acid-base balance
3. muscle contraction and nerve transmission
4. 30-40% stored in bone crystals - easily accessible to maintain blood levels
110
sodium deficiency
unlikely - generally eat more salt than needed
111
strict low-sodium diet
used for hypertension, kidney diseases or congestive heart failure
112
causes of sodium deficiency
1. vomiting
2. diarrhea
3. extremely heavy sweating
113
endurance athletes and sodium
endurance athletes can lose so much salt and drink so much water they become hyponatremic
114
symptoms of hyponatremic
1. headache
2. confusion
3. stupor
4. seizures
5. coma
115
maintenance of sodium
1. body absorbed sodium freely
2. kidneys filter excess sodium out of blood into urine
3. kidneys conserve sodium
4. small sodium losses occur in sweat
5. amount of sodium excreted in a day = amount ingested that day
116
salt and "water weight"
1. as blood sodium rises, a person get thirsty to drink until sodium-to-water ratio to restored
2. kidneys excrete extra water to remove excess sodium
- not fat gain, excess water which healthy body will excrete
117
how do you keep body salt and water weight under control?
controlling sodium intake and increasing water intake
118
adequate intake of sodium
1500 mg/day (14 and up)
119
CDRR for sodium
2300 mg/day (14 and up)
120
hypertension
salt (NaCl) seems to have a greater effect on blood pressure than either sodium or chloride alone
121
excess sodium intake and sex
males consume more excess sodium than females
122
sodium and blood pressure
1. more salt = higher blood pressure
2. increasing blood pressure = increasing risk of death from CVD
123
sodium and salt sensitivity
in salt-sensitive people, the more salt they eat the higher their blood pressure
124
salt-sensitive people
1. people with diabetes, hypertension or kidney disease
2. african descent
3. fam history of high BP
4. over age 50
125
reducing salt for high BP
only really need to if salt-sensitive
- try reasonable weight loss, adding fruits and veggies, fatty fish, milk/milk products
126
what diet approach may hep salt-sensitive and non-salt-sensitive people?
DASH diet
127
DASH meaning
Dietary Approaches to Stop Hypertension
128
DASH diet
1. increase veggies and fruits
2. nuts, fish, whole grains, low-fat dairy products
3. occasional red meat, butter and other high-fat foods and sweet s
4. salt and sodium greatly reduced
129
sodium and potassium relationship
1. low potassium intake found to raise BP
2. high potassium intake appears to both help prevent and correct hypertension
130
PA and BP
PA lowers BP
131
stroke and sodium
older people can die of stroke
- reducing sodium may lower blood pressure enough to reduce stroke risks
132
excessive salt
1. stresses a weakened heart (congestive heart failure)
2. aggravates kidney problems
3. may be potential contributor to stomach cancer
133
contributors to sodium in the diet
1. unprocessed foods (15%)
2. salt (10%)
3. processed foods (75%)
134
sources of sodium (processed foods)
1. canned soup and dried soup mixes
2. cured meats, deli meats, hot dogs
3. cheese
4. foods in brine (pickles, coleslaw)
5. TV dinners ans fast food
6. canned pasta sauce
135
how much sodium in 1 tsp of salt
2300 mg sodium
136
other sources of sodium
1. salt
2. soy sauce
3. onion salt
4. garlic salt
5. worcestershire sauce
137
chloride
major negative ion in the body
138
chloride function
1. acid-base balance
2. electrolyte balance
3. component of hydrochloric acid
139
sources of chloride
salt: both added and naturally occuring
140
chloride deficiency
no known diet lacks chloride
141
potassium
principle positively charged ion inside the bodys cells
142
potassium functions
1. maintenance of fluid balance
2. maintenance of electrolyte balance
3. maintenance of heartbeat
143
potassium deficiency and heart failure
may cause sudden death that occur with:
1. fasting or severe diarrhea
2. children with kwashiorkor
3. people with eating disorders
144
potassium loss
1. could be due to dehydration or diuretics
2. makes hypertension worse
145
sources of potassium
1. richest sources of potassium are fresh, whole foods
2. oranges (juice), bananas, potatoes, tomatoes, avocados, strawbs, spinach, cantaloupes
146
food processing and potassium
food processing reduces the potassium in foods
147
potassium toxicity
1. potassium from food is safe
2. potassium injected into vein can stop the heart
3. salt substitutes often contain high amounts
4. usually not life-threatening as long as the excess potassium is taken orally (vomiting reflex)
148
over the counter potassium chloride pills
should not be used except on a physicians/nurses advice
149
function of sulphur/sulphate
required for synthesis of many important sulphur-containing compounds
- sulphur containing amino acids
150
sulphur-containing amino acids
1. help strands of protein assume their functional shape
2. skin, hair and nails proteins with high sulphur
151
sources of sulphur/sulphate
protein containing foods
152
sulphur/sulphate toxicity symptom
diarrhea
