Transcript minerals ppt

MINERALS
MAJOR AND TRACE MINERALS
MINERALS
FUNCTIONS
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Components of enzymes  biochemical reactions
Bone, connective tissue formation
Blood formation, function
Metabolism of energy nutrients
Growth, reproduction
Nerve, muscle function
Membrane transport
Regulate body fluid balance
PROPERTIES
• Inorganic – no carbon
• Carry positive or negative charge
• May function together
calcium + phosphorus + fluoride = bone
• May act as individual elements
• Macro minerals essential in amounts
larger than 5 grams
MINERALS IN BODY
CALCIUM
CHARACTERISTICS
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Most abundant mineral in body
99% in the bone
Gives structure
“Bank” or reserve
1% in body fluids
Ionized calcium
Tightly controlled
CALCIUM CONTROL
• If blood calcium increases  bone
• If blood calcium decreases 
GI absorption increases
Bone increases release
Kidneys decrease excretion
• Regulated by hormones and vitamin D:
Parathyroid and thyroid glands
Parathormone  increases blood calcium
Calcitonin  inhibits calcium release from bone
BLOOD
CALCIUM
TOO HIGH
BLOOD
CALCIUM
TOO LOW
FUNCTIONS
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99% in bone and teeth
Contraction, relaxation of muscles
Blood clotting
Transmission of nerve impulses
Secretion of hormones
Activation of enzymes
Blood pressure
FUNCTION
ABNORMALITIES
• High blood calcium levels  calcium rigor
• Low blood calcium levels  calcium tetany
• Abnormalities  not dietary causes
CALCIUM ABSORPTION
• Increased need  growth, lactation, pregnancy
Adults absorb ~30%
Pregnant women ~50%
Infants, children ~60%
Growth hormone
Calcium binding protein (CBP) in intestine  increased
calcium absorption
• Acid environment
• Lactose – milk and milk products
• Vitamin D
BIOAVAILABILITY
CALCIUM SOURCES
COMPARISON
ABSORPTION
Decreased by:
• Phytic acid
oatmeal
whole grains
• Oxalic acid
rhubarb
spinach
• Factors increasing excretion:
excessive protein intake
excessive phosphate (PO4) intake
RECOMMENDATIONS
• Daily intake needed
• Adequate intakes established
Varies according to age
Same for adult male and female
No increase for pregnancy or lactation
• Tolerable upper intake limit established
DEFICIENCY
• Less than peak bone mass
• Osteoporosis in adults
• Rickets in children – bone malformation
BONE MASS
BONE MASS COMPARED
OSTEOPOROSIS
SPINE WITH
OSTEOPOROSIS
RISK
FACTORS
RICKETS
SUPPLEMENTS
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Calcium carbonate 40% (TUMS)
Calcium lactate  13%
Calcium gluconate  9%
Avoid bone meal, dolomite:
Contaminated with heavy metals – unsafe
• Aluminum and magnesium may increase calcium
loss
• Test for absorbability:
6 oz of vinegar, stir occasionally
75% dissolved in ½ hour
PHOSPHORUS
CHARACTERISTIC
• 2ND Most abundant mineral in body
FUNCTIONS
• Bones and teeth – 85% of mineral
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Calcium + phosphorus  hydroxyapatite
Buffer – phosphoric acid
Growth – DNA, RNA
Energy metabolism
activating enzymes and B vitamins
part of ATP, ADP, AMP
Major part of some lipids - phospholipids
Transport of nutrients in and out of cells
RECOMMENDATIONS
• RDA – varies according to age and gender
• Food sources:
all animal flesh foods, processed foods,
milk, milk products, soft drinks
DEFICIENCY AND EXCESS
• Deficiency is rare – bone demineralization
May result from high antacid intake
Preemies on human milk
• Excess – may increase calcium excretion
ELECTROLYTES
SODIUM, CHLORIDE, AND
POTASSIUM
SODIUM, POTASSIUM,
CHLORIDE
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Electrolytes to regulate fluids
Sodium (Na+) – major + ion: extracellular
Potassium (K+) – major + ion: intracellular
Chloride (Cl-) – major – ion: extracellular
SODIUM
FUNCTIONS
• Electrolyte – fluid balance
• Nerve impulse transmission
• Muscle contraction
RECOMMENDATIONS
• Adequate Intake
• Minimum – 500mg (Commission on Dietary
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Allowances)
Upper Level – 2300 mg
1 tsp salt = 2000 mg Na ~40%
Moderation:
Diet and Health Guidelines: 6gm salt = 2400 mg Na
Average intake:
Sodium = 4-6 gm/day
Salt = 10-12 gm/day
SODIUM
SOURCES
DEFICIENCY
• Not usually a problem – abundant sources in food,
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freely absorbed
Vomiting, diarrhea
Kidney disease
Extremely heavy sweating
Blood loss, extensive burns
Restricted intake of protein, salt
Hyponatremia = fatigue, confusion, dizziness
Extreme cases  coma
Only replace water  water intoxication
EXCESS
• Na levels regulated by kidneys – immediate
symptoms – edema and hypertension
• May contribute to but not cause hypertension (HTN)
• Genetic predisposition to HTN
• “Water follows salt”
Increase Na intake  increase blood volume 
increased pressure on vascular system
(Increased blood pressure)
CONTROL HTN
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Salt sensitive
Decrease sodium intake
Decrease weight when appropriate
Medication when necessary
Use salt substitute (KCl) only on advice of
MD
CHLORIDE
CHARACTERISTICS
• Ionic form of chlorine (poisonous)
• Chlorine is added to public water to kill
dangerous micro-organisms
• Chloride is NOT poisonous – is required
FUNCTIONS
• Chief anion in ECF  regulates fluid
balance
• Part of HCl  acts on protein to begin
digestion
• Maintaining acid-base balance
RECOMMENDATIONS
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Adequate Intake
Upper Level 3600 mg
Minimum requirement – 750 mg/day
Sources – abundant in diet
processed foods
table salt (NaCl)
DEFICIENCY
• In sodium depleting conditions
• As a result of human error
Infant formulas
Tube feedings
• Used in sweat test for cystic fibrosis
Increase Cl in sweat means positive tests for
cystic fibrosis
POTASSIUM
FUNCTIONS
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Main cation ICF for fluid balance
Facilitates reactions
Supports cell integrity
Nerve impulses
Contraction of muscles (**Heart)
RECOMMENDATIONS
• Adequate Intake – no upper level
• Food sources – fresh foods
K+ in every cell
fruits, vegetables, legumes
SOURCES
DEFICIENCY
• Muscle weakness  6% loss heart failure
• Can occur with low fruit and vegetable intake
• Abnormal conditions (hypokalemia)
Use of certain drugs:
diuretics
laxatives
steroids
DKA Diabetic ketoacidosis
Dehydration
Diarrhea
Prolonged vomiting
EXCESS
• Supplementation – not food
• Megadoses from pills cause:
muscle paralysis
abnormal heart rhythms – can stop heart
• Injections
MAGNESIUM
FUNCTIONS
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Significant cation in intracellular fluid
Essential to metabolism of CHO and PRO
Bone mineralization
Protein synthesis
Energy metabolism-essential partner in ATP
Muscle contraction, nerve transmission
(antagonistic to Ca)
• Prevents blood clotting (works against Ca)
• Teeth maintenance (works with Ca)
RECOMMENDATIONS
• RDA for males and females
• Food sources
All protein containing foods
Legumes, nuts, seeds, spinach, whole grain breads,
brown rice, seafood, chocolate, cocoa
Food processing decreases Mg content
significantly
• Stored in muscle
• Reservoir in liver and bone
DEFICIENCIES
• Mild – seen in those with:
protein malnutrition
alcohol abuse
renal, endocrine disorders
vomiting, diarrhea
use of diuretics
• Severe
neurological/nervous system
convulsions tetany seizurescoma
heart failure
TOXICITY
• From oral supplements
• When kidney function is impaired –
excretion is regulated by kidneys
TRACE MINERALS
CHARACTERISTICS
• Micro nutrient elements
• Essential in amounts less than 5 grams
• All trace minerals would hardly fill a
teaspoon
• Trace refers to amount - NOT importance
IRON
FUNCTIONS
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Hemoglobin – carries O2
Myoglobin – O2 reserve in muscle cell
Energy metabolism – release of energy
Involved in making of amino acids,
collagen, hormones, and neurotransmitters
IRON
ROUTES
IRON SOURCES
• Breakdown of hemoglobin – recycled
• Body stores – mucosal cells
ferritin
hemosiderin
• Food sources – GI tract
Muscle meats meat, fish, poultry (heme)
Heme sources better absorbed ~23%
MFP factor enhances absorption of non-heme
sources
Non-heme sources – 2-20% absorption
Egg yolks, enriched cereals or grains, vegetables, fruits
SOURCES
POOR SOURCES
• Milk and milk products – not good Fe
sources
• Iron skillets – contamination
• Supplements – absorption lower than food
sources
• Ferrous sulfate and iron chelate absorbed
the best
IRON ABSORPTION
• Body carefully regulates  poor exit route
• Buildup in body
• Increase absorption
Vitamin C – especially non-heme
MFP factor
Stomach acid
• Decrease absorption
Fiber and wheat bran
Antacids
Tannic acid (tea, coffee, nuts)
IRON DEFICIENCY
• Anemia – measure blood hemoglobin and transferrin
• 3 stages:
Fe depletion
Fe erythropoiesis
Fe deficiency anemia
• Population affected:
Women of child bearing age
Children (milk anemia)
Low income
• Symptom - pica
Anemia corrected in 2-3 months
6-12 months to replete stores
Pregnant women
Hemorrhage
ANEMIAS
EXCESS
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Body controls carefully controls
Rare  super enrichment
Damage to intestine leads to Fe overload
Hereditary defect  hemochromatosis
Increased deposits damage to GI tissue
and liver
RECOMMENDATIONS
• Women –15 mg
Diet provides 6 mg/1000 kcal
Needs unmet even at 12 mg/2000 kcal
Must choose foods carefully
May need a supplement
• Men – 10 mg
ZINC
FUNCTIONS
• Supports work of proteins
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Numerous enzymes in metabolic process
RNA, DNA synthesis  growth
Active form of vitamin A in retina for normal vision
Retinol binding protein for transport of Vitamin A
Taste perception – salt
Wound healing
Sexual development
Fetal development
Blood clotting
Hormones – insulin and thyroid hormone
DEFICIENCY
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Growth retardation
Impaired immune response
Vitamin A deficiency symptoms
General malnutrition symptoms
NOT widespread in developed countries
Population:
Pregnant women
Young children
Elderly
Poor
EXCESS
• Toxic  vomiting, diarrhea, exhaustion, death
• Lowers body’s copper retention 
degeneration of the heart muscle
• Increases cholesterol and lipids 
atherosclerosis
• Lowers HDLs and increases LDLs
• Galvanized containers with high acid foods 
toxic doses of zinc
TOXICITY
RECOMMENDATIONS
• RDA established
• Infants and children higher
• Food sources:
High protein foods – meats, poultry, liver
Whole grains, legumes, fruits, vegetables
• Absorption:
High fiber and phytates  decreased absorption
High copper diet  decreased absorption
• Supplements not recommended except for deficiency
• Zinc as a cold remedy  experimental
SOURCES
IODIDE
IODIDE
FUNCTIONS
• Component of thyroid gland hormones
• Hormones regulate:
BMR
Body temperature
Growth
Blood cell production
Nerve and muscle function
DEFICIENCY AND EXCESS
Deficiency
• Goiter  thyroid gland
• Cretinism – retardation of mental and
physical growth
Excess:
• Enlarged thyroid – increases blood flow to
get rid of excess
RECOMMENDATION
• RDA – small amount needed
micrograms
• Food sources
Seafood, iodized salt
Plants grown on iodide rich sources
FLUORIDE
FUNCTIONS
• Strengthens tooth structure
• Makes teeth resistant to caries
• Bone formation – may help prevent
osteoporosis
Deficiency
• Increase in dental caries
DEFICIENCY
• Increase in dental caries
EXCESS
• Fluorosis
• 8 times amount neededsevere mottling of
teeth, discoloration
• Mottling – 4 times amount needed
• GI distress
EXCESS
RECOMMENDATION
• Adequate intake
• Sources: fluoridated water (1ppm); fish, tea
FLUORIDE PERCENTS
SELENIUM
FUNCTIONS
• Antioxidant – cofactor for enzyme
glutathione peroxidase
• Works with enzyme to convert thyroid
hormone to active form  necessary for
iodide metabolism
DEFICIENCY
• Heart disease – Keshan disease – cardiac
myopathy
• Kashin – Beck – osteoarthritis
• Population affected:
TPN patients
Aids and PKU  low protein diets  low
selenium intake
Fish with high mercury content  decrease
bioavailability of selenium
TOXICITY
• Self – supplementation
• High doses  digestive system disorders
RECOMMENDATIONS
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RDA established – micrograms
Higher for pregnant and lactating
Gender differences
Food sources – organ meats, fish, grains
CHROMIUM
FUNCTIONS
• Maintain glucose homeostasis
Associated with insulin
Part of glucose tolerance factor
• Participates in CHO and lipid metabolism
Deficiency
• Diabetes-like condition
• TPN patients
CHARACTERISTICS
• Chromium picolinate is the best absorbed
form
• We absorb ½ of usual intake
• Deficiencies are difficult to produce
CHROMIUM
Toxicity
• None as a nutritional disorder
• After 6 years of 600 micrograms/day
Recommendations –none
Food sources – liver, unrefined foods, nuts,
whole grains, cheese, Brewer’s yeast,
vegetable oils
CLAIMS
• Chromium builds muscles, enhances energy
Sensitive measures of LBM show NO significant
increase in lean or muscle strength-done on males
in weight training
• Chromium enhances weight loss
Not supported by research. Loss with products
containing chromium picolinate AND high fiber
AND low calorie diet AND exercise
• Chromium retards aging by 25 years
Rat study comparing other forms of chromium
CLAIMS
• Chromium improves glucose tolerance in
diabetes mellitus
May improve glucose tolerance and
decrease dose of insulin or oral agent