Water & Minerals - Chapter 8 Flashcards
Water
- Most indispensable of all nutrients
- Can survive only a few days without water
- Makes up 60% of adult body
weight- Arteries, veins, capillaries, cells, tissues, organs
Functions of Water
- Transport vehicle for nutrients and wastes
- Universal solvent
- Body’s cleansing agent
- Lubricant/cushion for joints
- Protection for sensitive tissue
- Maintenance of body temperature
Water Balance
- Lose water everyday
- Must consume at least the same amount
Water Balance (Thirst)
- Pituitary gland signaled to release hormone – kidney shifts water back to bloodstream (urine output decreased)
- When blood too concentrated, or blood volume/pressure too low,
hypothalamus initiates nerve impulse to brain to trigger thirst - Lags behind lack of water
Water Balance (Dehydration)
- Loss of water
- Symptoms:
- Thirst ↓
- Weakness ↓
- Exhaustion ↓
- Delirium ↓
- Can lead to death
How much Water do we Need?
- DRI ≈ 80% of daily need for water
- Males: 13 cups of fluid from beverages and drinking water
- Females: 9 cups of fluid from beverages and drinking water
- Remaining water need is met from foods consumed
- Body produces water from the breakdown of energy-yielding nutrients
- Needs will vary based on many factors
Just Water?
- Water content of various foods:
- 100% - water, diet soft drinks, plain tea, unflavoured seltzer
- 99-95% - sugar-free gelatin dessert, clear broth, Chinese cabbage, celery,
cucumber, lettuce, summer squash, decaf black coffee - 90-94% - Gatorade, grapefruit, fresh strawberries, broccoli, tomatoes
- 80-89% - soft drinks, milk, yogurt, egg white, fruit juice, low-fat cottage cheese, carrot, fresh apple
Types of Water
- Hard Water
- Soft Water
Hard Water
- High concentrations of Ca and Mg
- May protect against hypertension and heart disease
Soft Water
- Principal mineral is Na
- May aggravate hypertension and heart disease
- May more easily dissolve certain contaminants
What types of contaminants can water contain due to its properties as a universal solvent?
Bacteria, viruses, toxic pollutants, heavy metals, organic chemicals (e.g., pesticides), and spills.
How do public water systems in Canada address water contaminants?
They remove some hazards, typically using chlorine.
What is a boil-water advisory and when is it issued?
Issued by local public health units when water is contaminated with disease-causing bacteria, viruses, or parasites, or when it becomes cloudy at the source.
What are the main types of water available in Canada?
- Tap water:
- Municipal water held to minimum purity standards.
- Home purifying tap water:
- Removes contaminants like lead and chlorine but does not eliminate microorganisms resistant to chlorine.
- Bottled water:
- Federally regulated, but mineral content can vary and may be subject to provincial or territorial regulations.
What has been the history of water quality and access between the Canadian government and Indigenous communities?
There has been a long and harmful history related to water quality and access.
How long have drinking water advisories lasted in some Indigenous communities?
Many communities have faced drinking water advisories lasting over 1 year.
What is an example of a community with a long-term drinking water advisory?
Neskantaga First Nation in Ontario has been under a boil-water advisory since February 1995.
What has the Canadian federal government promised regarding water quality in Indigenous communities?
The federal government has made many promises to end long-term drinking water advisories on public systems and reserves.
Where is most of the body’s water located?
Most of the body’s water is inside the cells, with some on the outside, and the remainder fills blood vessels.
What role do major minerals play in the body?
Major minerals form salts, and water follows salt.
How do cells manage salts?
Cells move salts across their membranes to prevent collapse or swelling
What are electrolytes?
Electrolytes are compounds that partly dissociate in water to form ions (electrically charged particles).
What happens when electrolytes are present in unequal concentrations on either side of a permeable membrane?
Water flows to the side with the more concentrated electrolytes.
What is fluid and electrolyte balance?
It is the proper amount and kind of fluid in body compartments, controlled by the movement of electrolytes.
How does the body control the flow of water?
The body uses energy to move electrolytes across compartments using transport proteins in cell membranes, which act as pumps (e.g., Na outside, K inside).
What can cause an imbalance in fluid and electrolyte balance?
Conditions like vomiting, diarrhea, or severe illness.
Why is electrolyte imbalance a medical emergency?
Severe imbalance can develop quickly, leading to serious illness and can be fatal, especially in eating disorders.
What are the 7 Major Minerals?
- Calcium (Ca)
- Phosphorus (P)
- Potassium (K)
- Sulfur (S)
- Sodium (Na)
- Chloride (Cl)
- Magnesium (Mg)
What are the Trace Minerals?
- Iodine (I)
- Iron (Fe)
- Zinc (Zn)
- Copper (Cu)
- Selenium (Se)
- Fluoride (F)
- Chromium (Cr)
- Manganese (Mn)
- Molybdenum (Mo)
Electrolytes (Functions of Minerals)
- Na, K, Cl
- Maintain water balance in cells and blood
- Na & K:
- Used in muscle contractions and nerve transmission
Body Structure (Functions of Minerals)
- Ca, P, Mg, F, Zn
- Bones and teeth
Structure of DNA, RNA phospholipids, and ATP (Functions of Minerals)
- P
- Energy Molecule
Protein Structure (Functions of Minerals)
- Fe, Zn, Ca, Se, I
- The protein and the element are bound to make a specific shape and thus
function, e.g., Fe and hemoglobin, I and thyroid hormone
- The protein and the element are bound to make a specific shape and thus
Cell Signaling & Communication (Functions of Minerals)
- Ca, Na
- Ca moves across cells as a messenger, stimulating proteins and cell activity
Antioxidant Defense (Functions of Minerals)
- Zn, Cu, Mn, Se, S
- Components of defense enzymes
What percentage of calcium is found in fluids inside and around cells?
1% of calcium is found in fluids in and around cells.
What are the main functions of calcium in the body?
- Transport of ions over cell membranes
- Nerve transmission
- Maintenance of normal blood pressure
- Muscle contraction (including heartbeat)
- Blood clotting
- Secretion of hormones, digestive enzymes, and neurotransmitters
- Activation of cellular enzymes
Where is 99% of calcium stored in the body?
99% of calcium is stored in bones and teeth.
What is the role of calcium in bones and teeth?
Calcium is an integral part of bone structure and serves as a storehouse for calcium, which can be released when needed.
What are the recommended daily intake values for calcium?
- DRI: 1,000 mg/day
- TUL: 2,500 mg/day
- Recommendations for children and adolescents are higher for peak bone mass.
What are some food sources of calcium?
- Milk products
- Some leafy green vegetables
- Calcium-set tofu
- Canned sardines/salmon (with bones)
Does calcium absorption vary by food source?
Yes, calcium absorption varies from different foods.
What does the body prioritize when regulating calcium?
The body prioritizes maintaining blood calcium concentration over calcium stores in bones.
What happens when blood calcium concentration decreases?
- The body adapts by:
- Mobilizing calcium from bones
- Increasing absorption of calcium by the small intestine
- Preventing calcium loss from the kidneys
How much calcium is absorbed by children from their diet?
Children absorb 60% of ingested calcium.
How much calcium is absorbed by pregnant individuals?
Pregnant individuals absorb 50% of ingested calcium.
When is peak bone mass typically attained?
Peak bone mass is typically reached by the late 20s to early 30s.
How much calcium is absorbed by healthy adults?
Healthy adults absorb 25% of ingested calcium.
What happens to bone mass after age 40?
After age 40, bone mass begins to decrease, but the loss can be minimized.
Why is sufficient calcium intake important in children and adolescents?
Sufficient calcium intake is important to help build peak bone mass during childhood and adolescence.
What is a result of calcium deficiency?
Calcium deficiency can lead to osteoporosis, which causes weak, brittle bones and increased risk of fractures.
Importance of Peak Bone Mass
Even though Adult A and B lost bone mass at the same rate, because Adult A had a higher peak bone mass, she
did not enter the bone mass danger zone by age 70. Adult B had a lower peak bone mass and had osteoporosis
by age 60.
What are the main functions of phosphorus in the body?
- Maintenance of acid-base balance of cellular fluids
- Part of DNA and RNA for tissue growth and renewal
- Metabolism of energy-containing nutrients
- Helps enzymes and vitamins extract energy from nutrients
- Structural part of phospholipids
- Present in some proteins
What are the recommended daily intake values for phosphorus?
- DRI: 700 mg/day
- TUL: 4,000 mg/day
Where is most of the phosphorus stored in the body?
Most of the phosphorus is stored in the bones and teeth.
What are symptoms of phosphorus deficiency?
Phosphorus deficiency (very rare) can cause muscular weakness and bone pain.
What is a potential toxicity of phosphorus?
Phosphorus toxicity can lead to calcification of soft tissues, particularly in the kidneys.
What are some food sources of phosphorus?
- Milk products
- Canned salmon
- Lean beef
What are the main functions of magnesium in the body?
- Assists with enzyme operation
- Release and use of energy from nutrients
- Affects metabolism of potassium, calcium, and vitamin D
- Forms part of protein-making machinery
- Affects muscle function (Ca: contraction, Mg: relaxation)
- Promotes resistance to tooth decay
Where is most magnesium stored in the body?
Over 50% of magnesium is stored in the bones.