NDFS 200 Final Exam- Water and Major Minerals

What factors influence water balance?

• water levels maintained by altering electrolyte concentration (water follows solute to maintain concentration)

• water moves via osmosis to maintain ion concentrations

• ADH pathway

• Angiotensin, renin, aldosterone pathway

What are the functions of water in the body?

• transport/blood volume

• fluid synthesis

• lubricate joints

• solvent

• reactant and product in many reactions

  • hydrolysis

  • condensation

• temperature control

  • sweat

• waste product removal

What are the functions of sodium?

• symport with glucose and amino acids

• muscle and nerve function

• water balance

What are the functions of potassium?

• major cation ECF

• fluid balance

• suppress angiotensin system

• muscle contraction

• calcium excretion

• nerve impulse

What are the functions of chloride?

• balance sodium

• stomach acid (HCl)

• nerve pulse transmission

What are the functions of calcium?

• bone

  • outer shell (compact bone, 75%)

    • replaces itself every 10 years

  • inner shell (spongy bone, add strength w/o weight, where minerals mobilized)

    • osteoclast activation

      • PTH and vitamin D activate Rankl production in osteoblasts

      • Rankl binds and causes osteoclast precusors to mature

• cell metabolism

  • ICF metabolsim

  • binds to calmodulin

  • calcium-calmodulin complex binds and activates enzymes that participate in metabolism

• nerve function

  • brings synaptic vesicles (Ca2+) to presynaptic plasma membrane so the neurotransmitters can be released

• blood clotting

  • prethrombin (+ vitK) → prothrombin (+ Ca2+) → thrombin (+ fibrinogen) → firbrinogen monomer

• muscle contraction

  • activation (Ca2+), cross-bridge, power stroke, ATP binds, release and cock

  • calcium binds to troponin to move trypomyosim and expose myosin to actin

What are the functions of phosphorous?

• bone

• main ICF anion

• ATP

• component of DNA

• hormone activation

• enzyme activation

  • phosphorylate amino acids with hydroxyl groups

What are the functions of magnesium?

• ICF cation

• stabilize ATP

• required by 300 enzymes

• calcium homeostasis

• nerve impulse

• insulin (may protect against diabetes and metabolic syndrome)

What do I need to know about sulfur?

EAT YOUR PROTEIN

What are good food sources of magnesium?

• in chlorophyll

• plants are a good source

What are good food sources of phosphorous?

• milk

• cheese

• cereal

What are good food sources of calcium?

• dark leafy greens

• dairy products

• fortified juices

What are good food sources of sodium?

• 10% comes naturally from food

• 75-80% comes from food processing and added salt

What are minerals?

• essential, inorganic elements needed for function, growth, and maintenance

• cannot be synthesized

• major = > 100 mg/day

• minor = < 100 m/day

• often lost in cooking and processing

What is dehydration?

• lack of water

• causes vomiting, fever, diabetes, diarrhea, exercise, heat

• symptoms:

  • mild to mod: dry mouth, fatigue, deep yellow urine, muscle weak

  • severe: kidney failure, seizures, delirium

What is water intoxication?

• excess water intake

• lead to hypnoatremia: dilutes serum proteins and sodium

• at risk: endurance athletes, infants, those with mental illness

How can nutrition help in preventing and treating hypertension?

• hypertension

  • excess salt can lead to increased BP

  • more common in African Americans

  • risk factor for: CVD, kidney disease, strokes, and decreased brain function

  • primary contributors: obesity, inactivity, alcohol, salt intake

• prevention and treatment

  • DASH diet

    • potassium rich, magnesium, calcium

    • low fat and low sodium

    • high fiber

What is the role of nutrition in bone health and the prevention of osteoporosis?

• diagnosed when bones become fragile

• most common in 50+ asians and caucasians

• more common in women

• better to “stock up” when younger

What are the intake recommendations for sodium?

• AI: 1500

• only 200 mg/day sufficient but it is really hard to get rest of nutrients with only 200 mg of sodium

What are the intake recommendations for potassium?

• 90% absorbed via active transport

• prevent hypokalemia and hyperkalemia

What are the intake recommendations for chloride?

• AI based on amount consumed with sodium (chloride is “heavier” than sodium 60:40 ratio)

What are the intake recommendations for calcium?

• RDA for post menopausal is higher

• UL is reduced for elderly to reduced risk for kidney stones

• bioavailability of food ranges greatly

What are the intake recommendations for phosphorous?

• we often exceed the RDA

• UL set to prevent potential decreased blood levels

What are the intake recommendations for magnesium?

• supplemental Mg is not absorbed well

• UL is set because too much supplementation can cause GI distress