Chapter 9: Water & Minerals
Minerals that aid in fluid balance
sodium, potassium, Cl,P, Magnesium
Minerals that aid in muscle contraction & relaxation
sodium, potassium, calcium, magnesium
Minerals that aid in transmission of nerve impulses
sodium, potassium, chloride, calcium
Water is a major _________; many substances, including glucose, dissolve in water
solvent
Simple Diffusion
substances move from high to low concentration
During fetal life, _________ is crucial for normal brain development.
thyroid hormone
When do water toxicity signs & symptoms occur?
when minerals accumulate in the body to such an extent that they interfere with the functioning cells
Is it possible with a well balanced diet to consume all of the vitamins & minerals needed w/o taking a supplement?
yes
Grow retardation & sexual maturation in children are signs of a __________ deficiency.
zinc
Aldosterone
- 1 of the 2 hormones that participate in the body's effort to maintain fluid balance - adrenal glands secrete this - aldosterone signals kidneys to reduce the elimination of sodium in urine, & as a result the kidneys return the mineral & water to the general circulation
Antidiuretic hormone (ADH)
- 1 of the 2 hormones that participate in the body's efforts to maintain fluid balance - in response to dehydration, posterior pituitary gland in brain releases antidiuretic hormone - antidiuretic hormone stimulates the kidneys to conserve water
T/F: Consuming vitamin D with meals that contain iron is the best way to increase your absorption of iron.
- False - vitamin C aids in the absorption of iron & should be consumed at meals when iron rich foods are present to aid in the absorption
Minerals
- group of elements in Earth's rocks, soils, & natural water resources; unlike vitamins, they're indestructible - BUT, they're water soluble & can leach out of food into cooking water - cant be synthesized - plants: obtain minerals from soil/ fertilizer - animals: obtain minerals when they consume plants & other animals or substances that contain them - ex: iron, calcium
The DASH diet used to help lower blood pressure is:
- high in fruits & veggies - low in cholesterol, sodium, saturated fats
Manganese
- important component & activator of many enzymes in the body - role in wound healing, metabolism, bone & cartilage formation & antioxidant function
Hemoglobin
- iron-containing protein in red blood cells that transports oxygen to tissues & some CO2 away from tissues - responsible for the red color of oxygenated blood
Importance of Potassium
- key role in maintaining proper fluid balance - associated with lower BP values - necessary for transmitting nerve impulses, contracting muscles - maintaining normal kidney function
Importance of Sodium
- maintaining normal fluid balance - necessary for transmission of impulses by nerves - transporting small substances (i.e. glucose, amino acids) into cells - functioning of muscles
Compared to plant foods, animals foods tend to be __(more/less)__ reliable sources of minerals, such as iron & calcium. why?
- more - b/c they have higher concentrations of these minerals - plant foods can contain substances that reduce the bioavailability of minerals, particularly calcium, zinc, & iron
Lean muscle tissue contains ___(more/less)__ water than fat tissue. By how much?
- more - lean: about 73% water - fat tissue: about 20% water
What happens if you lose close to 4% of body weight in fluids?
- muscles lose considerable amounts of strength & endurance
Function of zinc
- necessary for wound healing - sense of taste and smell - DNA synthesis - healthy skin - proper functioning of the immune system - essential for growth & development during pregnancy, childhood, adolescence
Fluoride
- not an essential nutrient - strengthens bones & teeth when ingested in small amts.
Increasing bone density when a person is young is the best defense against osteoporosis. This is accomplished by:
- obtaining adequate amounts of fluid - exposing skin to sunlight which stimulates the body's ability to form vitamin D; tho some need to take calcium & vit. D supplements - performing weight bearing exercises
Functions of water
- participates directly in chemical reactions (ex. digesting food) - transporting substances - removing waste products - lubricating tissues - regulating body temp & acid-base balance (proper blood pH) - major component of blood, saliva, sweat, tears, mucus, & fluid in joints
Who requires special solutions of water & electrolytes to prevent dehydration?
- people who are sick: esp. kids w/ fever, vomiting, diarrhea, increased perspiration
The AI of 1500mg/day for sodium does not apply to who:
- people who perspire heavily (ex. marathon runners) - people who work in extremely hot conditions
Sources of Magnesium
- plant foods are the richest sources - spinach, green leafy vegetables, whole grains, beans, nuts, seeds, chocolate
Describe the thirst response
- primary regulator of fluid intake - alerts you to the need to replenish water that was lost by sweating, etc. - stimulates people to drink fluids before severe dehydration occurs - people who are dehydrated & older than 60 dont sense thirst as accurately as younger adults - most people meet their water AI's by letting thirst be their guide
Dehydration
- rapid weight loss is a sign - very 16oz. (~0.5L) of water that the body loses represents 1lb. of body weight
Function of Kidneys
- remove drugs & metabolic waste products (i.e. urea) from bloodstream
Importance of Iodine
- required for normal thyroid function & for production of 2 thyroid hormones (collectively referred to as *thyroid hormone*)
Other food additives that contain sodium include:
- sodium nitrate - sodium citrate - monosodium glutamate (MSG): seasoning thats often added to foods served in chinese restaurants
__________ colored urine can indicate adequate hydration, whereas ______ colored urine may be a sign of dehydration.
- straw colored (light yellow) - dark
What can you do to enhance the absorption of a calcium supplement?
- taking only 500mg of calcium - ingesting it with meals - choose a supplement with vitamin D
Iodine Deficiency
- thyroid produces insufficient amounts of thyroid hormone & goiter develops - as a result of lack of thyroid hormone, iodine deficient people generally have low metabolic rates & elevated blood cholesterol levels - signs/ symptoms: fatigue, difficulty concentrating on mental tasks, weight gain, intolerance of cold temperatures, constipation, dry skin
Copper
- used to make several enzymes that act as antioxidants - involved in iron metabolism, immune function, collagen production
What are some foods that are among the richest sources of calcium?
- whole grain total cereal - cheese - yogurt - sardines - soy milk - milk - turnip greens - kale - tofu - black beans - ice cream
Sources of Iron
- whole grain total ready to eat cereal, baked beans, yosters, beef liver, pumpkin seeds, clams, peas, kidney beans - some of the iron is meat is present as hemoglobin & myoglobin; these forms are collectively referred to as *heme iron* - the remaining iron in meat, as well as iron in veggies, grains, supplements is *nonheme iron*
Sources of Zinc
- widespread in foods - red meat & poultry supply most of the zinc in the typical American diet
Minerals with known or possible roles in the body
1. major minerals: Ca, Cl-, Mg, P, K, Na, S 2. trace minerals: Cr(chromium), F, Cu (copper), I, Fe, Mn (manganese), Molybdenum (Mo), Selenium (Se), Zn (zinc) 3. Possible essential minerals: Arsenic, Boron, Lithium, Nickel, Silicon, vanadium (V)
Essential minerals are classified into what groups
1. major minerals: we require 100mg or more 2. trace minerals: less than 100mg 3. possible essential: body contains v v small amts. of these
Rank where water is lost in the body in order from the greatest source of loss to the least.
1. urine 2. insensible perspiration & sweat 3. expired air 4. feces
If extracellular fluid has an excess of sodium ions, what occurs?
1. water moves out of cells 2. as a result, cells shrink & die b/c they lack enough intracellular fluid to function
In the U.S., iron deficiency is the most common nutritional deficiency. An estimated _________ American children & adolescents have iron deficiency anemia.
16 million
What is the RDA for iron for adult women
18mg/ day
An average healthy adult consumes & produces ~_____mL of water & eliminates about ______mL of water daily.
2500mL
According to the World Health Organization, over _____% of the world's population suffers from anemia, & many cases of the condition are due to iron deficiency.
30%
About _____% of our total water intake is from water & other beverages; food supplies the remaining amount of our water intake
80%
Safety standards for bottled water are similar to those established by the _______ for tap water.
EPA
The body increases fluid conservation by producing hormones. The ______________ hormone forces the kidneys to conserve water. The kidneys respond by reducing urine flow.
antidiuretic hormone (ADH)
Functions of calcium
blood clotting, bone building, muscle function
According to the FDA guidelines, who is responsible for producing safe water products?
bottled water manufacturers
Sources of Selenium
brazil nuts, oysters, fish, egg noodles, turkey, sunflower seeds, ground beef, egg, baked beans, whole wheat bread, yogurt, soy milk, mushrooms
Leading Sources of Dietary Sodium In the United States
breads & rolls, deli meats, pizza, soups, cheese, salty snacks, dishes made with meat (ex. meatloaf w/ tomato sauce)
Minerals that aid in blood clotting
calcium
Minerals that aid in bone health
calcium, phosphorus, iron, zinc, copper, manganese, fluoride, magnesium
Minerals that aid in growth & development
calcium, phosphorus, zinc
Many minerals are components of various enzymes, hormones, or other organic molecules, such as:
cobalt in vitamin B12, iron in hemoglobin, & sulfur in amino acids methionine & cysteine
Some minerals, such as copper and magnesium, work as ____________, enabling various proteins, such as enzymes, to function.
cofactors
What drinks often contain caffeine of caffeine related compounds
coffee, tea, energy drinks
What happens if you lose 20% of body weight in fluids?
coma & death are likely
After RBCs die, the body breaks them down and:
conserves the iron from hemoglobin
Symptoms of iron toxicity include:
diarrhea & vomiting
Caffeine is a ________, which is a substance that increases urine production.
diuretic
Overall, minerals from animal products are better absorbed than those from plants b/c binders such as ____________ are not present to hinder absorption
fiber
What 3 foods provide most of the calcium in American diets?
fluid milk, yogurt, cheese
Most of the sodium Americans consume is from:
foods available from restaurants & the salt that is added to food during processing (including curing, pickling, canning)
Hereditary Hemachromatosis
genetic disease that causes people to absorb too much iron, resulting in iron overload
A high- sodium diet is associated with increased risk of ___________
hypertension
In what country was zinc deficiency first discovered
iran
Minerals that aid in cellular metabolism
iron, calcium, phosphorus, magnesium, zinc, chromium, iodine, copper, manganese
Bok Choy is a good source of minerals, especially _____, _____, & _____. the vegetable also contains high amounts of vitamin C.
iron, calcium, potassium
Minerals that aid in RBC formation
iron, copper
Myoglobin
iron-containing protein in muscle cells that controls oxygen uptake from RBCs
The water consumed in caffeinated beverages __(is/is not)___ completely lost in urine, do drinking these fluids may still contribute to meeting your water needs.
is not
Sometimes, minerals & waste products settle out of urine & collect into crystals. If the crystals enlarge & form a hard mass, the object is called a __________. These often contain the mineral calcium.
kidney stone
Magnesium toxicity most likely results from consuming excess _________
laxatives, antacids, or dietary supplements that contain it
Some ions, such as _______ and ______ are cofactors.
magnesium & copper
Groups of minerals work together to:
maintain good health
The body's ability to absorb & use minerals (bioavailability) depends on _________
many factors
_____ is a poor source of iron
milk
Many medical researchers think some people are genetically "sodium sensitive". A person who is sodium sensitive is:
more likely to develop hypertension as a result of consuming a high sodium diet than an individual who lacks this sensitivity
Many minerals have a __(wide/narrow)__ range of safe intake; therefore it's easy to consume a toxic amount, especially by taking supplements that contain only a particular mineral.
narrow
Describe "hard" water
naturally contains a variety of minerals: calcium, magnesium, sulfur, iron & zinc
Obtaining adequate amounts of calcium from foods and performing weight bearing exercises are good ways for a young person to prevent _________ later in life.
osteoporosis
Signs & Symptoms of Iron Deficiency Anemia
pale skin, fatigue & weakness, irritability, difficulty concentrating and thinking, brittle nails, headache
What happens if you lose 7- 10% of body weight in fluids?
results in severe weakness
Minerals that aid in Antioxidant Defense
selenium ,zinc, copper, manganese
Tips to reduce your sodium intake
- Read the Nutrition Facts panels before purchasing packaged foods to determine sodium contents of the items. - Prepare homemade meals and snacks as much as possible so you have control over your salt intake. - Do not add salt while preparing foods, even though instructions tell you to "add salt." - Taste your food before salting it - Adjust to eating foods with less salt in them. - Do not keep a salt shaker on your table. - When ordering items in restaurants, request that no salt be added to your food while it is being prepared.
Sulfur
- a component of several organic compounds, including amino acids methionine & cysteine, & the vitamins biotin & thiamin - essential for activity of many enzymes & as part of antioxidant molecules - protein rich sources are the best food sources of sulfur
Major Risk Factors of Hypertension
- advanced age - African Am. ancestry - obesity - physical inactivity - smoking cigs - excess alc & sodium intakes
Calcium
- all cells need it - more than 99% of the body's Ca is in an inorganic compound that forms the structural component of bones & teeth
Who specifically needs to stay properly hydrated to avoid dehydration & heat related illnesses such as heat exhaustion
- athletes - ppl who work/ exercise outdoors (esp. in hot conditions)
Why is advanced age a risk factor of hypertension
- b/c BP usually increases w/ age, probably in part b/c plaque builds up in arteries (atherosclerosis) & interferes w/ normal functioning of the blood vessels - healthy arteries are flexible tubes that expand w/ each heartbeat & recoil in b/w beats
Why do vegetarians have a higher risk of iron deficiency- related disorders than people who eat meat?
- b/c meat provides heme iron - combining a small amt. of meat w/ plant foods improves the bioavailability of the plant's nonheme iron - some plants contain high amounts of oxalic acid & phytic acid- substances that can depress iron absorption - on the other hand, vegetarian diets are usually rich in vitamin C, a factor that increases nonheme iron absorption
Perspiration
- body water that is secreted by sweat glands in skin - when it reaches the skin's surface, it evaporates into the air - this process helps cool the body & maintain its normal temp
Water intoxication
- can occur when an excessive amount of water is consumed in a short time period or kidneys have difficulty filtering water from blood - excess water dilutes the sodium conc. of blood, disrupting water balance - as a result of the imbalance, too much water enters cells, including brain cells - signs/ symptoms: drowsiness, nausea, vomiting, confusion, inability to coordinate muscular movements, weight gain
Fluorosis
- caused by long term consumption of too much fluoride - skeletal fluorosis: excess fluoride builds up in bones, causing joint stiffness & bone pain
What happens if you lose 1-2% of your usual body weight in fluids?
- causes fatigue & thirst - ex: if you weigh 150lbs, & u drop 3lbs after exercising in hot conditions, you've lost 2% of your body weight, primarily as water weight
Osteoporosis
- chronic disease characterized by loss of bone mass & reduced bone structure - people w/ this have weak bones that are susceptible to
Cretinism
- common in infants that are born to iodine deficient women - babies w/ this have permanent brain damage, reduced intellectual functioning & growth retardation - not treatable
Hypercalcemia
- condition characterized by a higher-than-normal concentration of calcium in blood - symptoms/ signs: bone pain, muscle weakness, fatigue; people w/ this can develop kidney stones
Hypertension
- condition characterized by persistently elevated blood pressure - serious public health problem in the U.S
Osmosis
- diffusion of a solvent (water) thru a selectively permeable membrane - concentration of substances dissolved in water influences osmosis - water moves from low solute concentration to high solute concentration
As a food additive, what does salt do?
- enhances flavors - can prevent the growth of microorganisms responsible for food spoilage
Importance of Chloride
- essential for maintaining proper fluid & acid-base balance - needed for transmission of nerve impulses & production of HCl in the stomach
Factors that influence bioavailability of zinc include:
- excess dietary copper - excess dietary iron - the body's need for zinc
Sources of Water
- fruit juice, milk, soup, coffee, tea, soft drinks, flavored bottled water - most solid foods contain some - fruits & veggies: contain 60-95% water weight
Iron
a component of hemoglobin & myoglobin - primary function: aid in O2 transportation
Cofactor
a metallic ion or small molecule that activates certain chemical reactions
Adequate Intake (AI) for total water intake is:
a. young women: ~11 cups (2.7L) b. young men: ~15.5 cups (3.7L)