review for test 4

o Minerals are micronutrients
o required in small amounts,
o inorganic
o do not provide energy.

> 100 mg/day

• Calcium
• Phosphorous
• Magnesium
• Sodium
• Potassium
• Chloride
• Sulfur

1 mg to 100 mg/day

• Iron
• Zinc
• Manganese
• Copper
• Fluoride

mcg to < 1 mg/day

• Selenium
• Molybdenum
• Iodine
• Chromium
• Boron
• cobalt( vit b12)

o grouped by how much is neede
• macroelements-
 more than 100mg/day/adults
• microelementes
 trace: I mg to 100 mg/day/adult
 ultra trace. < 1 mg sometimes mcg/day
 ultra trace- not proven to be essential

o Ca+ 99% found in bone and teeth
o important for blood clotting
o activates proteins in the cells

o Intestinal absorption, re-absorption by kidney and bone mineral turnover controlled by:
o parathyroid hormone (PTH), ( increase hydroxylation of vit d in to kidney to form calcitriol)
• released when drop in ionized Ca+ in blood –
• increases bone re-absorption and
• conserves kidney excretion
• increases intestinal calcium absorption
• increase Ca re absorption by kidney( less in urine)
• increase bone mineral resorption ( Ca relesased from bone)

o Intestinal absorption, re-absorption by kidney and bone mineral turnover controlled by:
o 1, 25-dihydroxyvitamin D (calcitriol):
o vitamin D by diet or sun,
o hydroxylated 1st by liver and
o 2nd by kidney to form active vitamin D –
o facilitates the absorption of Ca and P

o Milk and dairy products
o Fortified orange juice and ready to eat cereals

o Bone formation- osteoblast
o Bone resorption- osteoclast

o Lactose – increase absortion
o Dietary fiber-decrease absortion
o Phytate-decrease absortion
o Oxalate-binds with calcium and increases excretion.

o Calcium intake is half of what we need

o 2.5 g/day
o set to prevent kidney stones.
o Renal failure
o Calcification of bone tissue
o UL should protect people.

o Best way is bone mineral density: studies have helped to prevent

o Osteoporosis- weak bones, increases franctures can be due to combination of vit D and or low Ca intake.

o White women
o Small stature
o Smokers
o Poor Ca intake
o Lack of exercise.

o Intestinal
• Crohn’s disease, areas in intestine that get infected. Mostly in Jews
• Celiac
• Intestinal resection or bypass (poor fat absorption – vitamin D)
o Chronic liver disease:
• Impaired hydroxylation of vitamin
o Chronic renal failure
• Reduced synthesis of 1, 25 vitamin D

o Hypercalcimia
• Sarcoidosis: high calcitrol
• Hyperparathyroidism : high calcitrol
• Renal calcium stones : increased absortion
• Tumor production of a PTH like compound that increases calcium reabsorption and bone resorption

o second most abundant intracellular cation (K, Mg)

o Inversely proportional to the amount ingested
o 30-50% normally absorbed
o absorbed along the small and large intestine
o maximum absorption distal jejunum and ileum

o fiber from fruits, vegetable, grains decrease absorption but these foods are rich in Mg so not a problem
o phytates reduce absorption
o high phosphorus diet reduces absorption
o Low absorption if diet is low protein

o Kidney conserves Mg, when dietary intake is low, less than 12-24 mg excreted per day
o When Mg intake is high, rapid excretion in the urine
o High calcium or high sodium diets increase excretion of Mg
• Absortion-excretion=balance (kidney)

o UL is 350 mg/day of supplementary Mg
o Food sources no problem
o Mg salts as laxative- cause diarrhea.

o The ions of Na, K and CL are the principle electrolytes of body fluids.
o Play a role in;
• Electrolyte balance and current
• Osmotic control( how much water inside and outside cell)
• Transport of metabolites by cells

Electrolyte --intracell extracell
Na 12 145
Cl 2 110
K 150 4-5

o Sodium:
• 70% in the extracellular fluid
• controls osmotic effect

o Sodium
o hyPERnatrimia

o Low serum sodium can occur secondary to diuretics, vomiting, diarrhea, and can lead to dehydration as sodium is lost so is fluid.

o Salt (major source of Na)

Recommend salt intake is 6 grams per day or 2400 mg of Sodium.

o Minimum intake is 500 mg/day

o 40Na% and 60Cl%

o Heart muscle particularly vulnerable to low levels of K (hypokalemia)

o Potassium is the most intracellular cation

o meat, fish and dairy products
o fruits and vegetables

o Chloride is the most abundant extracellular anion

o Chloride required to form gastric acid

o Pyloric stenosis
o Spasms of the pyloric valve cause vomiting
o Loos of HCL
o Low blood chloride

o Major role is in the transport and metabolism of oxygen
o Hemoglobin and myoglobin – iron carriers

o Hemosiderin storage form of iron
o Can be detrimental to body if in large amt

o ---iron
o For women due to increased loss – 2.84 mg iron needed (unlikely to get adequate iron from diet)

Heme
o Hemoglobin and myoglobin

o Polyphenols (coffee and tea)
o Phytates( phosphorous containing compounds found in outer kernel of grain vegetables and legumes
o Calcium

o Gastric acid reduces ferric to ferrous ion, which improves absorption(ferric high in pH in duodenum)
o Factors that improve rate of absortion
• Adecuate HCL in stomach
• Vitamin C
• Heme iron eaten at the same time.

o Iron deficiency is the most common mineral deficiency in the US

o iron

hypochromic, microcytic RBCs, reduced O2 carrying capacity of blood
o pale

o In infants adverse psychomotor development
o Reduced work performance
o Adverse pregnancy outcome
o Reduced immune competence

o Iron overload – hemosiderosis
• Reported to occur in people heating food in iron pots or supplement overdose
• Today mainly due to hereditary problem
 Autosomal recessive inheritance

o water supply 0.05-6 ppm (most > 1.0 ppm)
o city water 0.7-1.2 ppm optimal range

o opacities and discoloration if the teeth endemic
o happens before the teeth erupt
o first called “Colorado brown stain”, now called dental fluorosis
o cosmetic problem not a health risk

o prevents dental caries: by Increasing resistance of enamel to acid
o prevents fluorisis

o Probable Toxic Dose (PTD) 5 mg/kg
o 3 year old drank a fluoride solution at the dentist containing 24-35 mg died
o another 3 year old died after eating 200, 1 mg tablets
o a 27 month old died after eating about 100 mg
o nausea and vomiting

o Trace elements

o Metallothionein may bind Zn in enterocyte
• Prevents Zn uptake to cells
• Sloughed off into intestine
o Diet high in zinc stimulates metallothionein production

o Inhibited by phosphate rich phytates
o Calcium and phytate at the same time enhance the effect
o High dietay calcium

o Seafoods (oysters)
o Meats (red and organ)
o Whole grain products and fortified grain

o Loss of appetite first sign
o Loss of taste sensation
o Growth retardation
o Described with high dietary phytate consumption and low meat intake
o Alopecia
o Hyperkeratinization of the skin
o Reproductive abnormalities

Zn

o Transported to liver and converted to ceruloplasmin, transported to tissues as ceruloplasmin
o Entire length of SI ( jejunum)

o Neutropenia
o Anemia

• Genetic disease
• Copper accumulation in the brain
• Lens of the eye
• Penacillamine is the treatment.
 Poor growth
 Abnormal bone
 Impaired glucose intolerance
 Poor reproduction
 Malformations in offspring

• Genetic defect – X-linked recessive , 1:300,000
• Low serum copper
• Low ceruloplasmin (copper transport protein)
• Low copper in liver and brain
• Increased copper in intestinal mucosa, muscle, spleen and kidney
• Hair is “Steely”
• Progressive cerebral degeneration

o Synthesis of thyroid hormone
o Sets metabolic rate for the whole body!

o Most reliable source is fortified salt-76 mcg/g salt

o Enlargement of the thyroid gland, goiter
o Decrease production of thyroid hormones
o Low levels of thyroid hormone in blood(t4) and increased TSH
o Leads to hyperplasia of thyroid gland ( goiter) and better uptake of urine.

o Cretinism
• Deficiency during the first trimester of pregnancy
• Neurological symptoms
• Mental retardation
• Deaf
• Spastic diplegia

o Hypothyroidism

o Selenium
o Cofactor for glutathione peroxidase
o Glutathione peroxidase is an anti-oxidant

o First recognized in China called Keshan disease
o Cardiomyopathy

needed to synthesize a cofactor for sulfite oxidases….discovery of an inborn error of metabolism proved the essential nature of Mo

• Iodine
• Molybdenum (no deficiency symptoms)
• Selenium

chromium