Download Unit 7 Water and Minerals Why is water so important? Water

Unit 7
Water and Minerals
Why is water so important?
Water
Comprises ______% of the body
Lean muscle tissue contains ______% water
Fat contains ______% water
Human body has no storage for water
Human body has a poor thirst mechanism
Intracellular and Extracellular Fluid
Intracellular fluid
Extracellular fluid
Osmosis
Osmosis:
Functions of Water
Body temperature regulation
Water absorbs any excess heat
Body secretes fluids via perspiration
Skin is cool as perspiration evaporates
Fluid Intake - Guidelines
Adult
Infants
Water in Foods
Beverages, fruits, and vegetables are _____% water
Potatoes, chicken, and steak are __________% water
Jam, crackers, and fats are ________% water
Water-Deficiency Diseases
Triggers thirst mechanism; not always reliable indicator
What if the Thirst Message is Ignored?
A Closer Look at Dehydration
1 – 2% loss of body weight leads to thirst
Fatigue
4% loss of body weight
Muscles lose strength and endurance
10 – 12% loss of body weight
Decreased heat tolerance and Weakness
20% loss of body weight
Coma and death
Water Toxicity
Too much water without sufficient electrolytes intake
Overwhelms the kidneys
Usually not a problem (people won’t drink that much)
Headaches, blurred vision, cramps, convulsions
Minerals
Two Types of Minerals
Major minerals (macrominerals) Require >
Trace minerals (microminerals) Require <
Major Minerals: Macrominerals
Daily nutritional need <100 mg/d: 7 essential major minerals
Sodium:
Source:
Sodium in Foods
80% intake comes from processes foods (More processes = ____________________)
10% added by individuals
10% naturally present in foods for example milk and dairy products
Functions of Sodium
Major ion in ______________________________________________ which means
it is important in _____________________________________________
Key for retaining body water
Conduction of nerve impulses
Sodium Needs
Adequate intake: 1500 mg/d for adults and 1200 – 1300 mg/d for older adults
Body only needs ~200 mg/d
Minimum requirement is 500 mg/d
Sodium -Deficiency Diseases
Rare
Consequences of deficiency
Treatment
Upper Level for Sodium
UL = 2300 mg/d and ~95% of North Americans exceed UL
Consequences of toxicity
Chloride/Chlorine:
Sources:
Table salt (60%), Chlorinated water, Seaweed, Olives, Rye, Some fruits
and vegetables
Functions of Chloride
Major ion in extracellular fluid which means it is important in water balance like
Na
Chloride Needs
AI = 2300 mg/d and average consumption = 5400 mg/d
Chloride-Deficiency Diseases
Unlikely due to high salt intake and water treatment
Toxicity
UL = 3.6 g/d and a high intake may cause hypertension
Potassium:
Found in fruits, vegetables, milk, grains, meats, dried beans
Generally not added to foods
Functions of Potassium
Potassium Needs
AI = 4700 mg/d
Excess potassium is excreted by the kidneys
No UL (only restricted in kidney diseases) = No Toxicity
Potassium-Deficiency Diseases
Rare
Causes:
Consequences of deficiency:
Calcium:
Calcium in Foods
Kale, collard, mustard greens
Calcium fortified foods
Tofu (if made with calcium carbonate)
Canned fish (with bones)
Functions of Calcium
Bone Mass
During growth, osteoblast exceeds osteoclast activity
More bone mass in areas under higher stress
Peak bone mass reached between the age of 20-30
Bone loss: Mid-adulthood and Menopause
Calcium-Deficiency Diseases
Osteoporosis: Loss of bone
Calcium Supplements
Calcium carbonate (40% calcium)
For those with ample stomach acid and is found in ____________________
Calcium citrate (21% calcium
Enhance absorption due to acidity content and is recommended for elderly
Calcium Needs
Adequate Intake (based on 40% absorption)
1000 - 1200 mg/d for adults and 1300 mg/d for adolescents
Upper Level for Calcium
UL = 2500 mg/d
Consequences of hypercalcemia
Functions of Phosphorus:
Found in every cell
ATP, DNA, RNA and Phospholipids
Phosphorus in Foods
Phosphorus Needs
RDA = 700 mg/d for adults and current intake exceeds RDA (1000 – 1600 mg/d)
Deficiency of Phosphorus
Deficiency highly unlikely
Consequences of deficiency
Upper Level for Phosphorus
UL = 3-4 g/d
Phosphate ions bind calcium
Calcium-phosphorus precipitates in body tissues
May compound bone loss if calcium intake is low
Functions of Magnesium:
Magnesium in Foods
Magnesium Needs
RDA: 310 mg/d for women and 400 mg/d for men
Average intake is lower than the RDA
Magnesium-Deficiency Diseases
Consequences of deficiency
Rapid heart rate
Weakness
Muscle spasms
Disorientation
Seizures
Upper Level for Magnesium
UL = 350 mg
Toxicity is uncommon
Consequences of toxicity
Sulfur:
Functions
Part of vitamins and amino acids
Aids in drug detoxification
Acid-base balance
Part of a natural diet, primarily from protein
Used to preserve foods
NO: RDA, Deficiency, UL and Toxicity
Trace Minerals: Microminerals
Needed in much smaller amounts; daily nutritional need <100 mg/d
9 essential trace minerals
Iron:
Source: Red meats, Enriched grains, Fortified cereals, Milk is a poor source
Functions of Iron
Hemoglobin in red blood cells (Transport oxygen and carbon dioxide)
Myoglobin in muscle cells
Immune function
Drug-detoxification pathway
Iron Needs
RDA :8 mg/d for adult males and 18 mg/d for females (11 to 50 y)
Iron-Deficiency Diseases
Most common form of anemia
Consequences of deficiency: Fatigue, Difficulty breathing, Poor growth
Upper Level for Iron
UL = 45 mg/d
Overdose can be serious: children
Causes: Repeated blood transfusions, Hemochromatosis (Overabsorb
iron→Deposition in tissues)
Consequences of toxicity: Stomach irritation, Increased formation of free radicals,
Death due to respiratory collapse (shock)
Zinc:
Source: Animal products, Shell fish, Legumes, nuts, whole grains
Not part of the enrichment process
Functions of Zinc
Protein and alcohol metabolism
Immune function: ↓ oxidation
Enzyme function: Catalyst or stabalization
Zinc Needs
RDA: 8 mg/d for women and 11 mg/d for men
Zinc-Deficiency Diseases
Consequences depends on severity of deficiency
Consequences of deficiency: Poor growth and learning, Impaired immune function
Acrodermatitis enteropathica (Skin lesions, hair loss, and diarrhea)
Upper Level for Zinc
UL = 40 mg/d
Consequences of toxicity: Inhibits copper absorption, ↓ HDL → ↑ risk of heart
disease, Diarrhea, cramps, Depressed immune function
Copper:
Source: Organ meats, Seafood, Cocoa, Legumes, seeds, nuts, whole-grain
Functions of Copper
Aids in iron metabolism
Forms Enzymes: Superoxide Dismutase (SOD) which is part of antioxidant system
Copper Needs
RDA = 900 µg/d for adults
Copper-Deficiency Diseases
Due to high zinc supplements
Consequences of deficiency: Normocytic, hypochromic anemia, Poor growth
Upper Level for Copper
UL = 10 mg/d
Not common (storage of Cu is tightly regulated)
People with Wilson’s disease accumulate copper in the liver, brain, kidneys, and
cornea; leads to premature death if left undetected
Selenium: Sources
Functions of Selenium
Glutathione Peroxidase System
Thioredoxin enzyme family (Protects the heart and other cells from oxidative
damage)
Selenium Needs
RDA = 55 µg/d
Selenium-Deficiency Diseases
Causes: Low intake due to low soil content
Consequences of deficiency: Muscle pain, Muscle wasting, Cardiomyopathy
Keshan disease: Heart disease in children, Accumulation of fatty acid peroxides in
the
heart, Increase blood clots, Irreversible
Upper Level for Selenium
UL = 400 ug/day
Consequences of toxicity: Garlicky breath, Hair loss, Nausea, vomiting, Weakness,
Rashes, and Cirrhosis of the liver
Iodide ( ) in Foods
Iodized salt (1/2 tsp. meets RDA), Saltwater fish, seafood, molasses, Sea salt is a poor
source (loss during processing), and Plant source
Functions of Iodide
Thyroid hormone synthesis: Metabolic rate, Growth, and Development
Iodide Needs
RDA = 150 µg/d
Iodide-Deficiency Diseases
Causes: Low intake (from low soil content), Consumption of goitrogens (↓ in thyroid
metabolism)
Consequences of deficiency: Growth of the thyroid gland (goiter), Drop in the
metabolic rate
Cretinism (Stunted growth during fetal development)
Upper Level for Iodide
UL = 1.1 mg/d
Consumption of seaweed
Thyroid hormone synthesis is inhibited
Fluoride ( ) in Foods
Fluoridated water (~0.2 mg/cup), Tea, Seafood, seaweed, and Toothpaste
Functions of Fluoride
Essential function has not been described
Role in prevention of cavities
Secreted in saliva, Aids in synthesis of fluorapatite crystals , Increased
mineralization of teeth, Resists acid, and Inhibits bacterial growth
Fluoride Needs
AI = 3.1 -3.8 mg/d for adults
Upper Level for Fluoride
UL: 10 mg/d for adults and 6 mg/d for children
Consequences: Mottling or weakening of the teeth in children, and Skeletal fluorosis
Prevention: Limit toothpaste to pea size for children
Food Sources of Chromium ( )
Eggs, Pork, Whole grains, nuts and mushrooms
Functions of Chromium
Aids insulin in signaling blood glucose to enter tissues
Needs: AI: 25 µg/d for women & 35 µg/d for men
Deficiency: High blood glucose levels
No UL = No Toxicity
Manganese ( )
Source: Oats, nuts, tea
Function: Cofactor for enzymes and in bone formation
Needs: AI:1.8 mg/d for women and 2.3 mg/d for men
No deficiency symptoms
UL = 11 mg/d
Nervous system disorders
Molybdenum ( )
Source: Legumes, nuts, grains
Function: aid enzymes (xanthine dehydrogenase)
RDA = 45 µg/d
Deficiency: NONE
UL = 2 mg/d
Only seen in animals (Poor growth)