32 - Minerals Flashcards Preview

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Flashcards in 32 - Minerals Deck (66):

Describe minerals

- Found on the periodic table
- Not broken down by digestion nor destroyed by heat or light
- Macrominerals: required at amounts >100mg/day
- Trace minerals: required at amounts


How much of minerals do we have of minerals in our bodies?

- More than a pound of calcium and phosphorus
- Also, potassium, sulfur, sodium, chloride, magnesium, etc.


Describe water balance

- Metabolic
- Foods
- Beverages

- Feces
- Lungs
- Skin
- Urine


What is the water intake recommendation?

Male = 3.7 L
Female 2.7 L


Describe water in the body

A decrease of 10% in body water can be life threatening


Describe the functions of water in the body

- Solvent
- Regulate body temperature
- Lubricate joints, digestive tract, eyes
- Transport


Describe the distribution of water in the body

- Body water weight associated with lean body mass
- 60% of body water – intracellular fluid
- 40% of body water – extracellular fluid (32% interstitial, 8% intravascular)


Describe electrolytes in the body

Electrolytes - anions and cations (Na+, K+, Cl-)
- Maintain electrical neutrality
- Help maintain pH
- Deficiencies rarely occur


Describe sodium in the body

- Major cation in extracellular fluid
- Freely filtered by glomerulus
- Regulates fluid movement
- Active reabsorption results in passive reabsorption of chloride, bicarbonate ions, and water (maintain neutrality of extracellular fluid & osmotic pressure


Describe potassium in the body

- Chief cation of intracellular fluid
- Cells: high potassium, low sodium
- Extracellular fluids: high sodium, low potassium
- Requires energy to maintain balance


Describe chloride in the body

- Primary extracellular anion
- Primarily absorbed as NaCl
- Reabsorbed by kidney (follows Na)


Describe the recommendations for sodium and potassium intake

- 1.5 g is adequate
- 2.3-4.5 is typical

Sodium chloride
- 3.8 g is adequate
- 5.8-11.3 g is typical

- 4.7 g is adequate
- 2.1-3.2 g is typical


Describe the dietary guidelines for sodium

The Dietary Guidelines for Americans, 2010 recommend that Americans aged 2 and up reduce sodium intake to less than 2,300 milligrams (mg) per day.

True dietary deficiencies of electrolytes typically not seen; low serum levels more likely to be due to a metabolic problem (e.g. refeeding syndrome leads to hypokalemia)


Describe the potassium to sodium ratio and its effects

- Pre-industrialization diet comprised of meat, vegetables, fruit. Today, largely comprised of processed/packaged foods
- Ratio of K/Na has shifted from 10:1 to 0.4:1


What is the effect of low potassium?

- Increased blood pressure
- Increased salt sensitivity
- Increased bone turnover
- Increased risk of kidney stones


Describe the acquisition of salt sensitive hypertension

- Normal kidneys are okay at handling sodium overlaod
- If any renal injury has occurred, it cannot excrete the sodium it needs to
- High sodium diet then leads to hypertension
- The BP will remain high even after the acute kidney injury has healed
- If they then have a drastic drop in salt intake, they will then experience hypotension because they have become "salt sensitive" in terms of BP control
- Example: get sick and don't eat for 2 days... Hypotension due to low salt will result


What is a salt substitute?

Potassium (sodium free) flavoring

Not good for patients with restricted potassium intake


Describe calcium in the body

Serum concentrations tightly regulated both intracellularly & extracellularly

3 hormones
- Calcitriol
- Calcitonin


What are the funcitons of calcium in the body?

- Bone health
- Muscle contraction
- Blood clotting (with vitamin K)
- Nerve conduction
- Enzyme regulation
- Membrane permeability


Describe bone health in relation to calcium

Approximately 99% of total body calcium is found in bone & teeth

Bone formation
- Calcium, protein, magnesium, phosphorus, vitamin D, potassium, and fluoride
- Other vitamins and minerals needed for metabolic processes related to bone formation
- Manganese, copper, boron, iron, zinc, vitamin A, vitamin K, vitamin C, and the B vitamins


Describe the requirement for calcium over a life span

- Requirement during adolescence is 1300 mg
- Bone mass peaks in 30s then begins to decline
- Declines more in women than in men (hormone changes)


Describe how the diet plays a role in calcium absorption

- Vitamin D has a large role (non-diet)
- Caffeine, alcohol and others can decrease absorption


Can calcium decrease hip fracture risk?

Yes - 300 mg/day calcium supplement


Describe phosphorous in the body

- Approximately 85% of body’s phosphorus is in skeleton, 14% in soft tissue, 1% in blood & fluids


What are the functions of phosphorous?

- Major anion within cells
- Contributes to ATP production
- Acid-base balance


Describe the absorption of phosphorous

- PTH & Vitamin D stimulate absorption
- Phytic acid (grains) decreases bioavailability
- Magnesium, aluminum, calcium impair absorption


Describe the excretion of phosphorous

- Balance maintained by renal excretion
- 67-90% excreted in urine; remaining in feces
- Dietary intake and absorption linear to excretion


Describe phosphorous deficiency

- Deficiency is rare
- Phos is present in most foods
- Body adapts to fluctuations by changes in excretion

Who is at risk....
- Premature infants
- Those receiving large amounts of calcium supplements or aluminum antacids (fight for same receptors)
- Malabsorptive disorders (Crohn’s)
- Alcoholism
- Uncontrolled diabetes
- Burns
- Refeeding syndrome


Describe magnesium in the body

Approximately 55-60% in bone, 20-25% in muscles; remaining in extracellular fluids


What are the funcitons of magnesium?

- Bone mineralization (forms the crystal lattice along with phosphorus and calcium)
- Cell membranes – bound to phospholipids
- Enzymes (>300 enzymes require magnesium to function): glycolysis, Krebs cycle, etc.


Describe the absorption of magnesium

- Phytate and fiber impair absorption
- Unabsorbed fatty acids bind magnesium to form soaps (excreted in feces)
- Vitamin D, lactose increases absorption
- Supplement coatings: absorption from enteric-coated magnesium-chloride supplements is about 67% less than gelatin-coated


What are other nutrient interactions

- Needed for PTH secretion; high concentrations inhibit secretion
- Needed for hydroxylation of vitamin D in liver
- Influence balance between extracellular and intracellular potassium
- Be aware that different supplements are formulated differently and you will need to adjust supplementation accordingly


Describe the function of chromium in the body

- Binds to nicotinic acid and amino acids to form glucose intolerance factor (Type 2 diabetes?)
- Glucose & lipid metabolism


What are the interactions of chromium with other nutrients?

May displace iron


Describe deficienicy of chromium

Glucose intolerance, insulin resistance, hyperinsulinemia


Describe supplementation of chromium

Available as inorganic salt (chloride) or as organic complex

Inorganic salt with chloride is better than the organic complex (side effects)

Can decrease fasting glucose in patients with type 2 diabetes


Describe the toxicity of chromium

Inhalation or direct skin contact with hexavalent form of chromium – respiratory disease, dermatitis and ulcerations


What is the most common dietary deficiency and most common cause of anemia world-wide

Iron deficiency


Describe iron in the body

Required for every living cell and organism


Describe the distribution of iron in the body

Hemoglobin contains over 65% of the body's iron
- 20-25% in blood or storage as ferritin
- 10% as myoglobin
- 1-5% as part of an enzyme


Describe the absorption of iron

This is the point of regulation ***
- Heme (animal sources)
- Non-heme (plan sources)

Non-heme enhancers
- Acids and sugars (when getting iron from plants)


What are the functions of iron?

- Center of heme molecule
- Transport of oxygen
- Component of enzymes (mono-oxygenase, dioxygenase, catalase, myeloperoxidase)


Describe the interaction of iron with other nutrients

- Ascorbic acid - enhances non-heme iron absorption
- Copper - iron is dependent on copper to be mobilized from storage
- Zinc - iron decreases absorption of zinc (competition in the gut)
- Vitamin A - iron decreases absorption
- Lead - inhibits activity of heme synthesis

Iron deficiency is associated with decreased selenium concentrations


What is the most common cause of anemia world-wide?

Iron deficiency

Also the most common dietary deficiency


What four groups are most susceptible to iron deficiency in the US?

- Infants and young children (low iron content in milk)
- Adolescents
- Premenopausal women
- Pregnant women
- (Also, those with chronic health conditions)


What are the symptoms of iron deficiency?

- Pallor
- Dizziness
- Palpitations
- Pica (eat non-food)
- Fatigue
- Dyspnea
- Angular stomatosis


What are the lab findings with iron deficiency?

- Decreased hemoglobin
- Microcytic anemia
- Decreased serum iron
- Increased serum TIBC
- Decreased serum ferritin

Note: iron deficiency CAN occur without anemia


Describe an iron overlaod

- Iron is very tightly conserved by the body and is constantly recycled
- Can lead to vomiting, diarrhea, eventually tissue damage
- Overdose of iron-containing vitamins common in children (acute overload)
- As for chronic overload, we see this in hemochromatosis, hemolytic anemia, idiopathic hereditary cases and iron-loading anemias such as thalassemia and sideroblastic anemia
- The treatment is frequent phlebotomy and chelation


Describe zinc in the body

Found in all organs and tissues, but mostly in liver, kidney, muscle, skin

Important for wound healing and skin integrity***

Antacids (H2 receptor blockers) and PPIs decrease the absorption of zinc from the diet


What are the functions of zinc?

- Component of enzymes
- Tissue and cell growth
- Skin integrity
- Bone formation
- Wound healing
- Immunosupression
- Carb methabolism (in insulin)
- Taste


Describe the use of dietary consultation in non-healing wounds (ASPEN)

- Can consult dietary with a non-healing wound
- Will determine nutrient or mineral deficiency
- Evaluate the patient
- If normal healthy patient, encourage high protein diet
- If the patient is low weight, low BMI or if they are not eating, they encourage calorie intake and also high protein, but also administer multi-vitamin and mineral pill
- If wound still does not heal, try vitamin C and zinc supplementation (huge role in skin integrity and wound healing)


What is the role of zinc supplementation in immunological status

- Beta-keratin, vitamin C and vitamin E all increase when taking zinc supplement
- This could be due to increase absorption or decreased excretion
- CD4 and CD9 lymphocytes are increased as well
- Zinc increases immunity ***


Describe the interactions zinc has with other nutrients

- Vitamin A - zinc deficiency is associated with decreased mobilization of retinol from liver
- Excessive zinc intake leads to decreased copper absorption
- Diminished calcium absorption occurs with suppleemnts
- Cadmium disrupts zinc functions by binding to the site
- Folate digestion requires zinc enzymes
- Lead may replace zinc in enzymes necessary for heme synthesis


Describe a zinc toxicity

- Metallic taste, nausea, vomiting, diarrhea
- Chronic supplementation of zinc (sickle cell anemia) can lead to a copper deficiency which can lead to iron deficiency


Describe a zinc deficiency

- Body reserves are quickly exhaused
- Growth retardation
- Skeletal abnormalities
- Poor wound healing


Describe the case of the man with pica ate coins

- Ate coins
- Gave him a zinc toxicity
- Surgically removed
- He had a zinc level well above normal
- Lead to a copper deficiency well below normal range
- Ceruloplasmin was therefore decreased as well (copper containing enzyme)


Describe the two oxidation states of copper

Cu+ and Cu++


What are the functions of copper?

- Enzyme cofactor (accepting and donating electrons)
- Gene expression by binding to transcription factors


What are the interactions of copper with other nutrients?

Zinc and iron implicate copper excretion and absorption

Also, molybdenum and selenium


Describe copper deficiency

Rare in US


What do we see when copper deficiency does occur?

- Hypochromic anemia
- Neutropenia
- Hypopigmentation
- Impaired immune function
- Demineralization of bone


What genetic disease are related to copper metabolism?

- Wilson's disease
- Menkes syndrome


Describe Wilson's disease

Wilson’s disease: defect in transporter required for biliary excretion (but not uptake); leads to accumulation in liver, brain, and kidney causing mental degeneration and liver damage


Describe Menkes syndrome

Menkes syndrome: defect in transporter that transports Cu to the fetus or through the intestine after birth, resulting in deficiency; symptoms appear in infancy and include slow growth, mental degeneration, kinky white hair


Describe copper toxicity

- Rare
- Usually occurs by water contamination, accidental ingestion
- Leads to nausea, vomiting, diarrhea, hematuria, jaundice


Describe the relationship between processing of foods and nutrient content

The more processed the foods, the less nutrients present