chapter 9: water and minerals

Water makes up how much of the human body

50-70%

Diuretic

A substance that increases urinary fluid excretion

Metabolic water

Water formed as a by product of carbs, lipid, and protein metabolism

How much water comes from food

2 cups

4 routes in which water is lost

Urine, perspiration, respiration, and feces

Sensible water loss

Water loss via urine

Insensible water loss

Water loss that cannot be measured

Antidiuretic hormone

A hormone that is secreted by the pituitary gland when the blood concentration of solutes is high, it causes the kidneys to decrease water excretion which increases blood volume

Angiotensin

A hormone produced by the liver and activated by enzymes from the kidneys. It signals the adrenal glands to produce aldosterone and also direct the kidneys to conserve sodium and water, both of these actions have the effect of increasing blood volume

Aldosterone

A hormone that is produced by the adrenal glands when blood volume is low, it acts on the kidneys to conserve sodium and water to increase blood volume

Increasing blood volume will increase

Blood pressure

How does liver make urea

When proteins are broken down nitrogen portion of amino acids cannot be used so it converts it to urea to be excreted in urine

Typical urine output ranges from

1-2 liters per day

Percentages of energy released in metabolism

40% energy cells can use atp

60% body heat

How does water regulate body temperature

Water resists rapid changes in temperature

Through evaporation, water releases heat into surrounding environment- increased body temperature causes vessel dilation and perspiration releases heat

Synovial fluid

Lubricant found in knees and other body joints

Hemoconcentration

Decrease in plasma volume, causing an increase in the concentration of red blood cells and other constituents of the blood

Inadequate fluid intake can cause

Kidney stones, when you’re in production is lower than 500ml (2 cups) per day, urine is concentrated, form from minerals and other substances that precipitate out of urine and accumulate in kidney

General guideline for athletes

Consume 2-3 cups of fluid for every pound lost

AI for water intake in females

Total water including food is 11 cups

Excluding food is 9 cups

AI for water intake in males

Total including food is 15 cups

Only fluid is 13 cups

Hard water

Water that contains high calcium and magnesium, 85% of homes have this

Soft water

Water that has high sodium

Artesian water

Comes from confined aquifer

Spring water

Must flow naturally to the surface

Mineral water

Comes from a ground source that is naturally high in minerals

Purified water

Produced through an approved process such as distillation or reverse osmosis

Water intoxication or hyponatremia

High intake of water, severe dilution of blood

Low blood sodium

Minerals make up about how much of body weight

4%

Major minerals

If we require more than 100 mg per day

Calcium, phosphorus, magnesium, sulfur, sodium, potassium, and chloride

Trace minerals

Required at levels less than 100mg per day

Iron, zinc, copper, iodine, selenium, molybdenum, fluoride, manganese, and chromium

Ultratrace minerals

Mineral present in diet but has not been shown to be essential

Arsenic, boron, nickel, silicon, and vanadium

Components of fiber can

Limit absorption of some minerals by binding to them

Phytic acid

Part of plant fibers that binds positive ions to its multiple phosphate groups

Oxalic acid

Acid found in spinach, rhubarb, and sweet potatoes that can depress the absorption of certain minerals present in food such as calcium

A large zinc intake will

Decrease copper absorption

Minerals from what products are better absorbed

Animal products

What minerals are stored in bones

Calcium, phosphorus, magnesium, and fluoride

What minerals are stored in liver

Iron, copper, zinc, and other trace

Vegetables are a source of

Magnesium and potassium

Fruits are a source of

Boron and potassium

Dairy is a good source of

Calcium, magnesium, phosphorus, and zinc

Salt composition

40% sodium and 60% chloride

Fluid in body percentages

63% intracellular fluid

37% extracellular fluid (interstitial fluid or plasma)

Four predominant electrolytes

Na+ and Cl- in extracellular fluid

K+ and PO4- in intracellular fluid

Sodium main functions

Served as electrolyte to maintain fluid balance

Contributes to nerve impulse conduction

Aids in absorption of certain nutrients (glucose)

Aids in maintenance of optimal calcium status

Fluid balance is regulated by

Pumping sodium ions where more water is needed

At rest nerve cell is

Polarized slightly negative inside

When nerve cell is stimulated then

Cell depolarizes and positively charged sodium ions rush into the cell

Hyponatremia

Low blood sodium

AI for sodium

14 and older is 1400 mg

Younger than 1200 mg

Reduce intake to 2300 mg

Potassium helps _______ bp

Lower

When sodium is pumped out of a cell, potassium

Enters the cell attempting to balance the loss of positively charged sodium ions

Intracellular fluid contains _________ of the potassium in the body

95%, potassium is the principal positively charged ion inside cells

Hypokalemia

Low blood potassium

AI for potassium

Males 3400 mg

Females 2600 mg

Suboptimal intakes of potassium may lead to

Cardiovascular disease

Does potassium have UL

No

Functions of chloride

Regulate fluid balance, responsible for bp increase

Component of HCl acid in stomach for acid-base balance, used during immune responses as wbc attack foreign cells, nervous system function

Good sources of chloride

Seaweed, celery, tomatoes, and olives

AI and UL for chloride

2300 mg

UL: 3600 mg

Second most abundant mineral in body

Phosphorus

Functions of phosphorus

Supports structure of bones and teeth

Serves as a portion of RNA and DNA and contributes to cellular replication and growth

Serves as a primary component of ATP

Contributes to cell membranes as a primary component of phospholipids, works with B vitamins, buffer

Most of dietary phosphorus comes from

Milk, cheese, meat, and bread

Vitamin D enhances

Phosphorus absorption

RDA for phosphorus

700 mg and 1250 for ages 9-18

Average daily consumption of phosphorus is

1200-1600 mg

UL for phosphorus

4000 mg per day

Too much phosphorus can

Mineralization of soft tissues, kidney problems, bone loss if calcium is low but phosphorus is high

Calcium represents what percentage of minerals present in body

40% and equals 2.5 pounds

All cells require

Calcium to function, more than 99% is used for growth, development, and maintenance of bones

Hydroxyapatite

Crystal compound containing calcium, phosphorus, and sometimes flouride, aka bone mineral

Responsible for structure and hardness of bone

Muscle contraction is activated by

Calcium release

Calcium functions

Bone growth, maintenance and repair

Normal muscle and nerve function

Regulates metabolism via various enzymes and hormones

Maintains cell membrane integrity, normal bp, glucose concentration, and cellular differentiation, blood clotting

How does calcium reestablish normal calcium level if decrease

Bones release calcium, small intestine absorbs more calcium, kidneys excrete less calcium into the urine