Download I. People Need Water

I.
People Need Water
 Instructor Resources: Unit 25 Nutrition Scoreboard transparency master; Unit 25 PowerPoint
presentation on Multimedia Manager
A. Water needs
1. Men - 12 cups per day
2. Women - 9 cups per day
3. Only live six days without water
B. Largest component of diet and body
C. Basic requirement of all living things
D. Water’s Roles
1. Water is an essential nutrient
2. Deficiency and toxicity possible
3. Body’s main source of fluoride
4. Medium for chemical reactions
5. Required for energy formation
6. Transports nutrients and waste products
7. Body’s cooling system
 Instructor Resources: Activity 25-1: Evaporation
E. 160-pound person has 12 gallons of water
1. Adults 60-70% water by weight
2. Water is in blood and between and in cells
3. Proportion of water in tissues varies
a. Blood is 83% water
b. Muscle 75%
c. Bone 22%
d. Fat cells are 10% water
II. Foods Contain Water
 Instructor Resources: transparency #70: Water Content of Foods
A. Water content of foods
1. Beverages are 85% water
2. Fruits and vegetables 75 to 90%
3. Meats are 50 and 70%
B. Water in foods contributes to our intakes
1. 31% of intake from plain water
2. 44% from other beverages
3. 25% from foods
III. Health Benefits
A. 10 cups each day associated with decreased risk of
1. Bladder cancer
2. Breast cancer
3. Colon cancer
4. Kidney stone formation
B. People feel and perform better when adequately hydrated
IV. Our Water Supply
A. Nearly 97% of world’s water is salty, only 3% is fresh
1. Of freshwater supply, 25% is available for use; 75% in polar and glacier ice
B. Fresh water available in the U.S., not true in other countries
1. In Russia drinking water dispensers are coin operated
2. Water is viewed as a precious resource
C. Water scarcity
 Instructor Resources: Activity 25-2: Fresh Water Shortages
1.
2.
Demand is increasing 100 to 500% per year in the world
Supply is dwindling; wasteful use of water, groundwater depletion, pollution, and leaky
public water systems contribute to shortages
3. Protection needed, or needs for agriculture and consumption limit food production and
increase incidence of water-borne illnesses
D. EPA sets maximum levels of contaminants
E. Water quality monitored by local water utilities
V. Bottled Waters
 Instructor Resources: Activity 14 in Instructor’s Activity Book: Bottled Water Taste Test
A. “Gourmet” Water
1. In U.S., “mineral,” “spring,” and “seltzer” waters have strong image
2. Mineral water from underground reservoirs and contains more minerals
3. Spring water from freshwater springs on the surface
4. Seltzers are naturally carbonated with CO2
B. Bottled Water Advantages
1. Calorie-free
2. Sodium-free or low in sodium
3. Quenches thirst better than soft drinks
C. Not purer than tap water
1. Some bottled waters contain tap water
2. FDA estimates 25% of bottled water sold in U.S. is bottled tap water
D. Is Bottled Water Safe?
1. FDA regulates the bottled water industry
2. Domestic bottlers must meet standards of safety and labeling requirements
a. “Mineral” or “spring” water must be that
b. Bottled tap water must be labeled as such
3. FDA requires bottlers to test their water
4. Imported waters tested upon entry to U.S.
E. Water Gimmicks
 Instructor Resources: ABC video clip on Multimedia Manager: Mineral Water (4:51)
1.
2.
3.
4.
Producers marketing “enhanced” bottled water fortified with everything from ginseng to
oxygen
Rationale for these products elusive
Safety of combinations of herbs put into bottled water is unclear
Adding oxygen to beverages is not useful
VI. Need for Water
A. Individuals require enough water to replace water lost in urine, perspiration, stools, and exhaled
air
B. Physically inactive people need two cups of water for every 500 calories consumed
1. People consuming 200 calories daily need 8 cups, those consuming 3000 calories need 12 cups
C. Built-in thirst mechanisms protect people from too much or too little
D. People working in hot, humid weather need more
1. Amount varies, often a 50% increase
E. Special Needs
1. Prolonged vomiting, diarrhea, and fever increase water need
2. High-protein and high-fiber diets, and alcohol use, increase water need
a. High protein consumption causes losses, people on high-protein diets drink extra water
b. Fiber increases water loss in stools
c. Increased loss of water with alcohol intake
F. Water Deficiency
1. Deficiency of water leads to dehydration
2. Dehydrated people feel very sick:
a. Nauseated
b. Fast heart rate
c. Increased body temperature
d. Feel dizzy
e. Find it hard to move
3. Fluids produce quick recovery
4. Dehydration can lead to kidney failure and death
G. Water Toxicity
1. People can overdose on water
2. High intake leads to:
a. Hyponatremia -or low blood sodium level
b. Excessive water accumulation in the brain and lungs
c. Consequences of confusion, severe headache, nausea, vomiting, seizure, coma, and death
3. Water intoxication occurred in:
a. Marathon runners who consumed too much water during an event
b. Infants given too much water or over-diluted formula
c. Psychotic patients taking medications that produce cravings for water