Week 12: Major and trace minerals & water Flashcards
(50 cards)
1
Q
What are 2 examples of major minerlas
A
calcium and sodium
2
Q
What are 3 examples of minor minerlas
A
Iron, zinc, iodine
3
Q
Describe the 4 roles of calcium in the body
A
- Calcium in bones - Hydroxyapatite are crystals of Ca.
- Calcium in body fluids
-> The body detects changes in extracellular Ca & responds
-> Extracellular Ca participates in blood clotting
-> Intracellular Ca binds to proteins in the cell & activates them - Disease Prevention
-> Calcium may protect against hypertension - Helps with maintaining healthy body weight (Ca2+ from
dairy foods)
4
Q
describe the steps to maintain blood calcium when levels are too high
A
- signals thryoid gland to secrete calcitonin
- calcitonin inhibits activation of vit d and prevents calcium reabsorption in kidneys, limits absorption in intestines and inhibits osteoclast cells from breaking dow bone, prevents release of caclitonin
- all steps lower blood calcium lvls, inhibiting calcintonin secretion
5
Q
describe the steps to maintain blood calcium when levels are too low
A
- singals parathyroig gland to secrete parathyroid hormone
- hormone stims activation of vit d
- vit d + hormone stims ca reabsorption in kidneys and osteoclast cells to break down bone, releasing ca into blood
- vit d enhances absorpption in intestines
- all raise blood ca inhibits parathyroid hormone secretion
6
Q
What are 4 factors that enahcne acalcium bsorption
A
- Stomach acid (solubility)
- Vitamin D > (calbindin)
- Lactose.
- Growth hormones.
7
Q
What 6 factors inhibit calcium absorption
A
- Lack of stomach acid.
- Vitamin D deficiency.
- High phosphorus intake.
- High-fibre diet.
- Phytates (seeds, nuts &
grains) - Oxalates (rhubarb & spinach)
8
Q
What are commo food surces of calcium
A
- dariy foods, brocoli, cauliflower, greens
9
Q
What is the rdi for calcium for men and women
A
- Men (19–70 yr): 1000 mg/day
- Women (19–50 yr): 1000 mg/day
10
Q
What is the UL for calcium
A
: 2500 mg/day
11
Q
How can people maximise bone mass
A
- Children & adolescents need to
consume enough calcium and vitamin D to create denser bones. - With a higher initial bone mass, the
normal losses of bone density that
occur with age will have less
detrimental effects.
12
Q
Descibe osteoporosis
A
- Trabecular bone losses can result in type 1, more common in women
- Can result in compression fractures of the spine
- Hip fractures can develop
- Diagnosis performed using bone density tests
(DEXA)
13
Q
What are the 3 roles of sodium in body
A
- Primary electrolyte in the body
- responsible for maintaining fluid balance (extracellular cation)
- Helps maintain acid/base balance
- essential in muscle contraction and nerve impulse transmission
14
Q
What are 3 common food sources of sodium
A
salt; processed foods;
many ‘fast’ foods;
15
Q
What are 3 symptoms of sodium defiency
A
muscle ‘spasticity’, mental apathy, loss of appetite.
16
Q
What can sodium toxicity/high intake led to
A
oedema and acute hypertension
- assoc’d with Ca excretion & bone loss (Osteoporosis).
17
Q
What is sodium Ai for males adn feamels
A
460-920 mg
18
Q
Where is iron found in body
A
part of haemoglobin and myoglobin.
19
Q
What is the iron rdi for men and women
A
Men: 8 mg/day; women (19–50 yr): 18 mg/d;
20
Q
What is the UL for iron
A
45mg/day
21
Q
What are the 5 roles of iron in the body
A
- Utilisation of energy in cell metabolism.
- Cofactor to enzymes involved in making amino acids, collagen, hormones & neurotransmitters all require iron.
- Forms part of electron carriers(cytochrome) of the electron transport chain
- Part of the protein haemoglobin, which carries oxygen in the blood
- Part of the protein myoglobin in the muscles, which makes oxygen available for muscle contractions.
22
Q
Describe the steps of iron absorption
A
- mucosal cells in the intestine store excess iron in mucosal ferritin ( a storage protein)
- if body doesn’t need iron, its not abrosbred and excreted
- body needs iron-> mucosal ferritin released iron to mucosal transferrin, hands off iron to another transferrin that teavels thru blood to rest of body
23
Q
What does iron defiiceny lead to and 3 synmptoms
A
- anaemia - most common nutrient deficiency worldwide
- Energy metabolism is impaired/neurotransmitter synthesis is reduced
– Fatigue, weakness, headaches, apathy, pallor
– Poor resistance to cold temperatures
– Physical work capacity and mental productivity are reduced (i.e. unmotivated, apathetic, less active)
24
Q
What are 3 common examples where iron is I higher demand
A
- Women in reproductive years due to menstruation.
- Pregnant women due to the needs of the infant, increases in blood volume, and loss of blood during birth.
- Infants and young children due to rapid growth.
25
What disease does iron toxicity lead to and 3 symptoms
- Haemochromatosis.
– From repeated blood transfusions (bypass intestinal defence).
– From massive doses of supplemental iron.
- Symptoms include apathy, lethargy and fatigue
- infections thrive on iron high blood
- linked to cancer and heart disease.
-i ron poisoning (large doses from iron supplements) can cause constipation, nausea, vomiting and diarrhoea
26
What are 3 common foos sources of iron
- oysters, liver, meats, legumes
27
What is the rdi of zinc men and women
Men: 14 mg/d;
Women: 8mg/d
28
What is the UL for zinc
40mg/day
29
What are 4 symtpoms of zinc defieincy
- Occurs in pregnant women, young children, the elderly and the poor.
– Growth retardation.
– Delayed sexual maturation.
– Impaired immune function.
– Hair loss, eye and skin lesions.
30
What are 4 symptoms of zinc toxicity
Causes loss of appetite, impaired immunity, low HDL, Cu/Fe deficiencies
31
What a re 3 common food sources of zinc,
oysters, sirloin steak, minced meat
meat fish, pultry
32
What does iodine become in the body
iodide
33
Waht is the rdi for iodine and the UL
- RDI (adults): 150 μg/day.
- Upper Level: 1100μg/day
34
What are 3 common food sources of iodine
Iodised salt, seafood, plants from iodine rich soil
35
Iodine is a essential compartment of what hormone? Explain the roles of the hormone
- Component of two thyroid hormones (T3 and T4)
–control the rate at which the cells use oxygen, therefore influencing the amount of energy released during basal metabolism
– Regulates body temperature, growth, development, metabolic rate, nerve and muscle function, reproduction and blood cell production.
36
What are 2 deficiency symtpoms of iodine
- Goitre
- Cretinism (From severe def.inpregnancy)
37
What are 3 reasons for iodine toxicity and 3 symtpoms
- Supplement use,medications and excessive iodine from foods.
- Symptoms include underactive thyroid gland, elevated TSH and goitre.
38
Describe intracellular and extracellular fluid
- Intracellular fluid makes up about two-thirds of the body’s water.
- Extracellular fluid has two components – the interstitial fluid, lymph and plasma.
39
What is water intoxication
is excessive water contents in all body fluid compartments – rare occurrence.
40
What is dehydration
ccurs when water output exceeds input due to an inadequate intake or excessive losses.
41
Describe the dehyrdation symptoms corresponding to the amount of body weight lost (4)
1–2 per cent loss of body weight – thirst, fatigue, weakness, vague discomfort and loss of appetite.
3–4 per cent loss of body weight – impaired physical performance, dry mouth, reduction in urine, flushed skin, impatience and apathy.
5–6 per cent loss of body weight – difficulty in concentrating, headache, irritability, sleepiness, impaired temperature regulation, and increased respiratory rate.
7–10 per cent loss of body weight – dizziness, spastic muscles, loss of balance, delirium, exhaustion, and collapse.
42
What are 5 roles of water in the body
- carries nutrients and waste products.
- Solvent for minerals, vitamins, amino acids, glucose and others.
- Lubricant and cushion around joints, inside the eyes, the spinal cord and in amniotic fluid during pregnancy.
- Regulation of body temperature.
- Maintains blood volume.
43
What are common sources of water
Water and other beverages.
* Fruit, vegetables, meat & cheese.
* By-product of metabolism.
44
How does water losses occuer, and how much water output per day
through urine output, water vapour from the lungs, sweating and faeces.
- output of 1450 to 2800 millilitres of water
45
What is the Ai for water for males and femaels
- Adequate Intake for males:3.4L/day.
- Adequate Intake for females: 2.8L/day.
46
What are the 2 health effects of water
- Protects the bladder, prostate and breast against cancer.
- Protect against kidney stones.
47
Describe fluid and electrolyte baalnce
– Dissociation of salt in water into ions = electrolytes.
– Electrolytes attract water.
– Movement occurs via ‘Osmosis’.
* Proteins regulate flow of fluids and ions.
48
Describe how fluid/electrolye balance is regulated
- Digestive juices of GI tract contain minerals and these are reabsorbed as needed.
- Kidneys maintain fluid balance using antidiuretic hormone (ADH).
- Kidneys maintain electrolyte balance using aldosterone.
- Medications and medical conditions may interfere with fluid and electrolyte balance.
- Vomiting and diarrhoea causes sodium losses.
49
What are the 3 systems that defend the body against pH fluctuations.
- Regulation by the buffers – Carbonic acid and bicarbonate can neutralise acids and bases.
- Respiration in the lungs – Respiration speeds up and slows down as needed to restore homeostasis.
- Excretion in the kidneys – The urine’s acidity level fluctuates to keep the body’s total acid content balanced.
50
