Major Minerals Flashcards
The more a food is processed, the greater the ratio of potassium to sodium
true
Bone health involves a variety of minerals. Select all that apply for full mark
Selected Answers:
Phosphorus Vitamin D Vitamin K Magnesium Sulfur
Selected Answers:
Phosphorus
Magnesium
minerals not vitamins
Which of the following is a parameter considered when making the distinction between major and minor/trace minerals?
5.
How much of these minerals are needed by the body?
Chloride is the main _____________
Answers:
1.
Cation in extracellular fluid
- Anion in intracellular fluid
- Electrolyte in interstitial fluid
- Cation in intracellular fluid
Correct5.
Anion in extracellular fluid
5.
Anion in extracellular fluid
In addition to its role in bone development and maintenance, calcium is also required for:
Vitamin D absorption, muscle contraction and neurotransmitter production
- Magnesium absorption, blood clotting function, and blood pressure regulation
Correct3.
Blood clotting, transmission of nerve impulse, muscle contraction
- ATP stabilisation, muscle contraction, and DNA synthesis
- Regulating potassium excretion, kidney function, and regulation of intracellular fluid
Response Feedback:
These are the typical functions of calcium besides in bone health. Look at the pictures in the lecture material that illustrate them.
Blood clotting, transmission of nerve impulse, muscle contraction
The DASH is a prescriptive dietary approach to address primary hypertension. Which of the following best describe the mechanisms of actions of the DASH (select all that apply for full mark):
Low fiber intake to avoid bile excretion and promote entero-hepatic circulation
- High carbohydrate and low fat intake to promote appetite control and weight loss
- A high sodium to potassium ratio to promote water excretion
- A high dietary calcium and magnesium intake for blood vessel vasodilation and relaxation
- A high potassium to sodium ratio to promote water excretion
Correct4.
A high dietary calcium and magnesium intake for blood vessel vasodilation and relaxation
Correct5.
A high potassium to sodium ratio to promote water excretion
acid found in dietary fibre interferes with mineral bioavailability for absorption. All Answer Choices Citric Oxalic Phytic Phenolic Acetic Ascorbic Amino
Correct Phytic acid found in dietary fibre interferes with mineral bioavailability for absorption.
hytic acid in fibre and oxalic acid is green leafy vegetables (but not associated with the fibre in these vegetables)
Match the following anions and cations with the right fluid compartment where they mostly prevail: ECF or ICF
Potassium magnesium Phosphate SUlfur Sodium Calcium CHloride Bicarbonate
Potassium ICF magnesium ICF Phosphate ICF SUlfur ICF Sodium ECF Calcium ECF CHloride ECF Bicarbonate ECF
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On your travel overseas you buy a packet of local crisps. You are curious about the sodium content in a 100 grams of crisps. The NIP is limited on the packaging; it indicates that the 125 g packet of crisps contains 5.35g of salt. How much sodium (in mg) is this equivalent to per 100 g of crisps?
Correct Answer:
Correct 1,682.04
Which of the following is most likely to be secreted first when blood calcium levels drop: [A]
Parathyroid hormone
In the usual diets of populations in developed countries, the sodium content comes from the following sources:
1.
77% from processed /restaurant foods, 12% from naturally occurring in food, 6% from adding salt to the meal, 5% from cooking with salt
- 77% from cooking with salt and soy sauce, 10% from natural food sources, 10% added to the plate, 3% from packaged foods
- 77% from naturally occurring foods, 12 % from processed /restaurant foods, 6% from cooking with salt, 5% from adding salt to the meal
- 77% from cooking with salt and savoury sauces, 12% from naturally occurring in foods, 6% from processed /restaurant foods, 5% from adding salt to the meal
- 75% from processed /restaurant foods, 25% from sauces added to dishes, 25% from natural food sources
Correct1.
77% from processed /restaurant foods, 12% from naturally occurring in food, 6% from adding salt to the meal, 5% from cooking with salt
Which of the following is likely to be secreted first when blood calcium rise above the normal range:
Calcitonin
High potassium diet reduces [A] excretion
Calcium
Calcium homeostasis is tightly regulated by a number of hormones which includes (select all that apply for full mark):
1.
Aldosterone
- Calcitriol
- Insulin
- Thyroid hormone
- Calcitonin
- Calcitriol
Calcitriol promotes
bone resorption - Calcitonin
Review the diagram about calcium homeostasis: calcitriol, calcitonin and PTH are the hormone to remember overall for that mechanism
On the nutrition information panel of a bottle of barbecue sauce, you see that there is 1150mg of sodium per 100 mL of sauce. You estimate that you are consuming about 40 mL of sauce with your dinner meal. How much salt ( in mg) is this equivalent to?
Correct Answer:
Correct 1,170
Answer range +/-
10 (1160 - 1180)
Review the calculations to convert sodium to salt and vice-versa
Bone is the main storage of ______________ whilst muscles contain a significant amount of ___________.
Magnesium, calcium and phosphorus; magnesium
Remember the Traditional Mediterranean Diet from your lipid week studies? What do you think: is it overall low in ______________ and high in ______________?
1.
Sodium; potassium
[A] acid found in green leafy vegetables interfere with mineral bioavailability for absorption.
Oxalic acid found in green leafy vegetables interfere with mineral bioavailability for absorption.
The NRVs for sodium include:
Selected Answer:
5.
The SDT of 2000 mg
Answers:
1.
The UL of 3000 mg
- The AI of 2300 mg
- The RDI of 2300 mg
- The EAR of 200 mg
Correct5.
The SDT of 2000 mg
5.
The SDT of 2000 mg
High potassium intake promotes:
Sodium excretion
Both deficiency and excess of _________________ lead to_______________:
Potassium; cardiac arrhythmia
- Chloride; failure to thrive
- Phosphorus; respiratory failure
- Sodium; muscle cramping
- Calcium; decreased magnesium absorptio
Potassium; cardiac arrhythmia
Potassium; cardiac arrhythmia
Mineral absorption is influenced by numerous factors. Which of the following statement is incorrect:
1.
Calcium is best absorbed in the upper duodenum
- Calcitriol increases phosphorus absorption
- Tannins and polyphenols enhance minerals absorption
- Vitamin D deficiency results in impaired calcium absorption
- A valence of 2+ promotes minerals absorption
3.
Tannins and polyphenols enhance minerals absorption
Salt substitutes often contain
Potassium chloride
Mineral essentiality is based on the following EXCEPT:
The fact that the body does not produce minerals endogenously
- The fact that deficiencies, if not addressed early, may lead to permanent health consequences
- How depleted in the specific minerals the soil in the region is
- How crucial these nutrients are to health despite low amounts required
- The fact that deficiencies result in identifiable characteristic symptoms
3.
How depleted in the specific minerals the soil in the region is
All of the following play a role in calcium homeostasis EXCEPT: [A] All Answer Choices 1,25 (OH)2 cholecalciferol Calcitonin Thyroxine Parathyroid hormone Thyroid gland Parathyroid glands
Thyroxine
What are the major minerals
Calcium phosphorus potassium sulfur sodium chloride magnesium
what impairs bioavailability of minerals
Excess fibre (above 38 g/day) may lead to lower mineral status
- Phytic acid found in fibre (phytate in legumes and whole grains): binds to minerals
& results in mineral excretion
- Leavened breads with baker’s yeast may break the bonds between phytates and
the minerals: ↑ bioavailability of minerals
• Oxalic acid in dark green leafy vegetables (not associated with fibre) binds minerals
and makes them less available for absorption
- E.g. calcium in spinach: 5% versus 32% absorbed for calcium from dairy
• Polyphenols and tannins can reduce bioavailability of iron and calcium in particular
- E.g. tea black, dark chocolate, red wine contain high amount of tannins that
interfere with iron absorption
• Consumption of several minerals of the same valence at once can decrease
absorption of each (e.g. in multi-minerals supplements):
- E.g. Zinc (2+ ); iron (2+ ); calcium (2+ ) and other 2+ valences compete for
absorption when taken together
what improves bioavalibility of minerals
Vitamin C: improves non-haem iron absorption within the same meal
• Stomach acidity: assists in converting minerals from 3+ to 2+ : helps their absorption
(because 2+ is the absorption form for minerals)
Therefore antacids may impair bioavailability of minerals, because of reduced
stomach acidity
• Good vitamin D status facilitates dietary calcium absorption (because calcitriol
upregulates expression of TRPV6 (calcium channel proteins), calbindin and calcium
ATPase-pumps)
• In general, human absorption of minerals increases when needs are greater
• NOTE: mineral content listed on labels doesn’t reflect actual absorption, but the
content in the tablet. Before using supplements, a full nutrient status analysis should
be performed.
functions of sodium
Maintenance of intra and extracellular fluid volume (including plasma and interstitial fluid) 2. Assists in the absorption of glucose and amino acids in the small intestine (e.g: SLGT for glucose) 3. Muscle and nerve function: membrane potential of cells 4. Note: salty taste is appetizing. Promotes food intake in anorexia
calculating sodium salt
Table salt = NaCl; 39.3% of salt is sodium
• Multiply by 0.393 the amount of salt to know how much sodium is contained in a
given amount of salt
• Divide amount of sodium by 0.393 to find out to how much salt this is equivalent to
• E.g: SDT for sodium = 2000 mg / 0.39= 5 128 mg = ~5 g = ~1 small teaspoon of salt (all
inclusive throughout the day)
sodium deficiency
Deficiency
• Hyponatremia: headache, nausea, vomiting, muscle cramps, fatigue, disorientation,
cerebral edema fainting and coma if left untreated rapidly
• Occurs when losses exceed intake: with excessive diarrhea and vomiting, or
excessive sweating (>2% of total body weight)
excess sodium
Toxicity
• Hypernatremia due to excessive water losses => low blood pressure, fainting, stupor,
convulsions
Other effects in high intake:
• >2 g /day can increase urinary calcium losses
• Salt-sensitive people: primary hypertension (25-50%) and thus increased risk of heart
disease and stroke
Potassium
Major cation in intracellular fluid
2. Contractility of smooth, skeletal and cardiac
muscle, and excitability of nerve tissue: responsible
for changing the electrical potential during
depolarisation / repolarisation of nerve/muscle
cells for conduction of impulse
3. High (dietary) potassium intake reduces serum
calcium excretion
4. High potassium intake promotes sodium + H20
excretion: resulting in reduced blood volume, and
reduced blood pressure in HTN.
This is the main mechanism of action of the DASH
(see further)
potassium deficiency
Deficiency
• Hypokalemia leads to cardiac arrhythmia, muscle weakness, fatigue, hypercalciuria,
glucose intolerance
• Usually due to profound fluid loss rather than lack of intake: vomiting, diarrhea, use of
diuretics, eating disorders, alcoholism (poor diet), athletes with excessive sweating
Potassium toxcicity
Toxicity
• Hyperkalemia results in cardiac arrhythmia and cardiac arrest, muscle weakness and
temporary paralysis, gastrointestinal ulceration and perforation.
Does not occur from dietary intake, but through supplements use, or use of salt
substitute: potassium chloride (to replace salt in low-salt diets)
In chronic kidney disease: potassium is not well excreted; restriction of dietary potassium
is required, which affects quality of life because many foods are limited or excluded. Use
of potassium binders may also be prescribed.
Chloride
- Electrical neutrality: balancing sodium positive charge
- Main anion for ECF
- Fluid balance
- Acid/base balance
- Nerve impulse transmission
- Component of:
- NaCl
- HCL
chloride deficiency
Deficiency
• Loss of appetite
• Failure to thrive
• Muscle weakness, lethargy, convulsions
• Severe metabolic alkalosis on blood test
Deficiency is usually rare as it is consumed as part of salt. Has occurred in infants fed
chloride deficient formula. May occur in GIT disorders with excessive diarrhea and
vomiting.
CALCIUM HOMEOSTASIS
ELEVATED - calcitonin
function of calcium
1- Bone development and maintenance:
• Forms calcium-hydroxyapatite with phosphate:
• Strong lattice-like structure that binds to collagen
• Hydoxyapatite allows strength of bone
• Collagen allows flexibility
• Bone remodeling: total skeleton replaced every
10 years through the activity of:
- Osteoblasts: build bone
- Osteoclasts: break bone
2- Blood clotting: calcium involved in the blood clotting factors formation cascade.
Ca binds to the gamma carboxy-glutamic acid in prothrombin (activated through the
gamma carboxylation with vitamin K as cofactor)
3- Muscle contraction:
• Calcium ions released when nerve impulse
reaches myocytes
• Calcium triggers muscle proteins to
contract
• When calcium is transported back into
the intracellular storage site: relaxation of
muscle fibre
Tetany= spontaneous nerve impulses from
too little calcium, results in muscle spasms
4- Transmission of nerve impulses: influx
of calcium ions when nerve impulse
reaches cell
• Trigger vesicles recruitment to
presynaptic membrane
• Vesicles release neurotransmitters
which carry the impulse across the
synapse into target cell
5- Other function:
• Helps decrease blood pressure by
smooth muscle relaxation in blood
vessels
BONE HEALTH
Bone health: Bone building nutrients include more than just calcium: protein, vitamin D, vitamin K, vitamin C, potassium, magnesium, phosphorus, copper, fluoride Active lifestyle with weight bearing exercise at critical age (until 25-30 years is ”bone building age”)to build maximum bone mass Drug therapy to reduce osteoclasts activity = bisphosphonates
calcium deficiency
Deficiency
• Hypocalcemia: muscle cramp, paresthesia, confusion, fatigue,
anxiety
• Low and very low bone mass: osteopenia and osteoporosis
calcium toxcicity
Toxicity
• Hypercalcemia can lead to kidney stones, high blood pressure
(calcification of blood vessels), renal calcification and failure
• High risk of toxicity with supplements: at above 1500 mg daily=>
risk of calcium deposit in coronary artery.
• If using supplements: calcium carbonate and calcium citrate
appear best; mays be combined with vitamin D3 or calcitriol
(prescription). Limit to 500 mg dose and take with food
• Risk of interference with absorption of other minerals : e.g. iron,
zinc, magnesium
DASH DIET
High potassium to sodium ratio*: high K intake promotes sodium and water
excretion, reducing blood volume and thus HTN.
*The DASH is about the combination of both high K and low Na (or “high K/Na ratio”;
or “low Na/K ratio”)
2- High in magnesium intake, high calcium intake: magnesium and calcium act as
smooth muscle relaxant and vasorelaxant e.g. blood vessels elasticity is maintained,
thus allowing for adaptation to blood volume and reducing HTN.
3- Low in sodium (down to 1500-2300 mg): for salt sensitive individuals, this will reduce
water retention, e.g. blood volume and thus HTN.
In overweight subjects, high salt intake tends to promote more food intake because it
is appetizing, worsening the energy balance and struggles to lose weight. Excess
weight is a risk factor for HTN. So if relevant for that person, weight loss can assist in
reducing HTN.
4- Moderate total fat, low saturated fat and low cholesterol intake: improvement of
blood lipid profile, reducing the risk of LDL build up and peroxidation, and thus risk of
arteriosclerosis which hardens the arterial wall, and narrows the lumen leading to HTN.
5- High fibre: can assist in appetite control to avoid over-snacking where over-weight is
an issue, and the resulting weight loss can reduce HTN.
Fibre also contributes to reduced cholesterol “re-absorption” via bile reabsorption,
which results in reduced blood cholesterol when new bile is made by the liver. This
improves the lipid profile and reduces arteriosclerosis risk, thus reducing the risk of HTN
via the hardening of blood vessels.
6- Avoid added sugar: improves blood glucose management which reduces the risk of
endothelium damage due to inflammation, and thus the risk of arteriosclerosis
development and the related effect on HTN.
7- High in vegetables and fruit provides plant sterols. What is the mechanisms that may
prevent HTN?
How are phosphorus, calcium and magnesium involved in bone health specifically?
phosphorus - 85% found in bones and teeth as hydroxyapatite
• The rest is in all other cells and ECF
Magnesium- 50% found in bone: as part of calcium-hydroxyapatite
Calcium- - Bone development and maintenance:
• Forms calcium-hydroxyapatite with phosphate:
• Strong lattice-like structure that binds to collagen
• Hydoxyapatite allows strength of bone
• Collagen allows flexibility
describe steps when calcium up or down
a- When blood calcium levels drop
parathyroid releases parathyroid hormone to 1. Stimulate calcium release from bones 2. Increase calcium uptake in intesitnes 3. Increase calcium retention in kidneys
b- When blood calcium levels rise to excess
calcitriol 1. Decrease calcium release from bones 2. Increase calcium excretion in kidneys
