Chapter 9

Intake of sodium and potassium affect our risk for hypertension

Minerals are solid, stable inorganic elements

Minerals are ions Elements with positive or negative charge

Minerals sturcutal function

  • Part of hormones and enzymes
  • Transmit nerve impulses
  • Maintain fluid balance
  • Support the immune system
  • Act with enzymes as cofactors to facilitate chemical reactions
  • Work in partnership with other minerals

Major minerals: >100 mg/day -

  • Sodium
  • Potassium
  • Chloride
  • Calcium
  • Magnesium
  • Phosphorus
  • Sulfur

Trace minerals:

  • Iron
  • Zinc
  • Copper
  • Iodine
  • Selenium
  • Molybdenum
  • Fluoride
  • Manganese
  • Chromium

Bioavailability is affected by nutritional status

  • Deficiency
  • Increased need

Presence of binders in foods

  • Phytates
  • Oxalates
  • Polyphenols
  • Other minerals

minerals found in

  • plants
  • whole unprocced foods
  • animal food
  • tap water

Bone formation and maintenance Calcium Magnesium Phosphorus

Calcium (Ca) is the most abundant mineral in the body

99% in bone and teeth

1% in cells and fluid

Blood levels of calcium are closely controlled through the process of calcium homeostasis

RDA = 1000 mg/day for adults 19 to 50 years of age

Achieving a higher peak bone density decreases the risk of osteoporosis as one ages

to much calcium and fortified

High dietary intakes may cause: Constipation Interference with iron absorption Hypercalcemia

Magnesium (Mg) is a cofactor in more than 300 chemical reactions in the body

  • 50-60% in bones
  • function: transport ions across membrane
  • role in protein production
  • necessary for vitamin d

Approximately 60% of American adults do not meet the magnesium recommendations

do meet require meant: cancer, atherosclerosis, hypertension, osteoporosis

to much: diarrhea, nausea, and abdominal cramping

Phosphorus (P) is present in every cell of the body

function: component of bon and cartilage, phospholipid, DNA and RNA; energy metabolism, regulates enzyme, maintain acid base balance

Sulfur (S) occurs in our diets as a component of other compounds

Present in two amino acids Cysteine and methionine Present in B vitamins Thiamine and biotin

Sodium (Na+), potassium (K+), and chloride (Cl–) are electrolytes that maintain fluid balance in the body

Sodium (Na+) is the primary electrolyte in extracellular fluid

function: regulating fluid balance, blood pressure, nerve impulse, contracting muscles

most sodium is from processed, packaged foods

AI = 1500 mg/day UL for adults = 2300 mg/day Average intake in Unites States = 3400 mg/day 1 teaspoon table salt (sodium chloride) = 2400 mg sodium

Overconsumption of sodium increases risk of hypertension

The DASH eating plan has been found to be an effective approach in helping lower blood pressure and reduce the risk of heart disease

Potassium is the primary electrolyte within cells

function: regulates fluid balance, cofactors certain enzymes, nutrient transport

Mild forms Increase risk of hypertension, stroke, and heart attacks

Potassium toxicity results only from supplement misuse

low heart rate and abnormal heart rhythm

Supplementation prescribed and monitored by a health care provider

Chloride is an electrolyte also found in extracellular fluids

 

Two-thirds of water is intracellular One-third of water is extracellular Water moves by osmosis

Inadequate or excess water intake can have adverse—possibly deadly—effects

Deficiency = dehydration Nausea Dizziness Elevated temperature Concentrated urine

Excess water consumption without electrolytes = hyponatremia Confusion Nausea Vomiting Bloating Swelling around the brain