Nutrition Chapter 9
Hypercalcemia
various diseases and metabolic disorders can alter our ability to regulate blood calcium; __________ is a condition in which blood calcium levels reach abnormally high concentrations; it can be caused by cancer and by the overproduction of PTH; symptoms include fatigue, loss of appetite, constipation, and mental confusion, and it can lead to liver and kidney failure, coma, and possible death
Scurvy
vitamin C deficiency disease caused by failure of collagen synthesis 312
Cholecalciferol
vitamin D3, a form of vitamin D found in animal foods and the form we synthesize from the sun
prothrombin
vitamin K supports blood health by acting as a coenzyme that assists in the synthesis of a number of proteins that are involved in the coagulation of blood, including _________ and several proteins called procoagulants 311
Cholecalciferol
when UV rays of the sun hit the skin, they react with 7 dehydrocholesterol,; this compound is converted into ________, which is also called provitamin D3; this inactive form travels to the kidneys where it is converted into calcitrol
Parathyroid hormone
when blood calcium levels fall, the parathyroid glands are stimulated to produce _________; _______ stimulates the activation of vitamin D; __________ increases absorption of calcium in the kidneys, while ___________ and vitamin D stimulate osteoclasts to break down bone, releasing more calcium into the bloodstream; in addition, vitamin D increases the absorption of calcium from the intestines
iron status
when iron stores are high, the amount of iron absorbed in the diet is low; however, iron absorption rates are higher in people with poor __________, such as those with iron deficiency, pregnant women, or people who have recently experienced blood loss 304
hydroxyapatite
within our bones, calcium and phosphorus form tiny crystals called ____________ that cluster around the collagen fibers; this design enables bones to bear weight wile responding to our demands for movement 315
regulatory functions of zinc
zinc helps regulate gene expression and thus the body functions that these genes control; for example, without zinc, certain genes that help regulated cell division during fetal development are not expressed 308
enzymatic functions of zinc
zinc is required for more than 300 different enzymes in the body; without zinc, these enzymes cannot function; for example, we require zinc for digestion and metabolism, and to synthezie the heme structure of hemoglobin 307
Structure of bone, nerve impulse transmission, muscle contraction, and blood clotting
Calcium is necessary for several body functions, including
T score
DXA is a very important tool in determining a person's risk for osteoporosis; it generates a bone density score, which is compared to the average peak bone density of a healthy 30- year old; doctors use this comparison, which is known as a ________ to assess the risk for fracture and determine whether the person has osteoporosis 317
Vitamin K
The micronutrient most closely associated with blood clotting is
Rickets
Vitamin D deficiency disease in children, called ________ is caused by inadequate mineralization or demineralization of the skeleton; the classic sign of rickets is deformity of the skeleton, such as bowed legs nad knocked knees; however severe cases can be fatal; _______ is not common in the US because of the fortification of milk products with vitamin D, but children with illnesses that cause fat malabsorption, or who drink no milk and get limited sun exposure, are at increased risk
Osteomalacia
Vitamin D- deficiency disease in adults is called ____________, a term meaning soft bones; with _________, bone beomces weak and prone to fractures; osteoporosis can also result from a vitamin D deficiency
Is essential for the synthesis of collagen
Which fo the following is a function of vitamin C
A fair skinned retired teacher living in a nursing home in Ohio
Which of the following individuals is most likely to require vitamin D supplements
They regulate the absorption of calcium and phosphorus form the small intestine
Which of the following is a function of vitamin D and PTH
It has a faster turnover rate than cortical bone
Which of the following statemens about trabecular bone is true?
About 2/3 of the body's iron is found in hemoglobin, the oxygen carrying compound in red blood cells
Which of the following statements about iron is true?
Cortical bone
_______, aka compact bone, is very dense; it constitutes approximately 80% of the skeleton; the outer surface of all bones is ________; plus, many small bones of the body, suc has the bones of the wrists, hands, and feet, are made entirely of ______________ 316
99%
________ of the calcium found in our body is stored in the hydroxapatite crystals built up on the collagen foundation of bone
50-60%
_________ of our body's magnesium content is found in our bones
teriparatide
_________, which is a synthetic form of parathyroid hormone and is used only in severee cases of osteoporosis, particualry in people with spinal fracture sor people with very low bone density, or when other treatments have not been effective, it helps new bone to form
hormone replacement therapy
__________ combines estrogen with a hormone called progestin and can reduce bone loss, increase bone density, and reduce the risk for hip and spinal fractures 339
80%
approximately ________ of Americans with osteporosis are women
heat and oxygen
because _________ destroy vitamin C, fresh sources of these foods have the highest content; cooking foods, especially boiling them, leaches their vitamin C, which is then lost when we strain them 313
Bioavailability
because iron status, stomach acid, the amount of iron in the diet, the type of iron in the fodos you eat, and other dietary factors alter the amount of iron aborbed, it is estimated that hte _____________ of iron from a vegan diet is approximately 1%-10%, whereas it averages 18% for a mixed-western diet 305
Collagen
because the body cannot form __________ without adequate vitamin C, tissue hemorrhage, or bleeding occurs; the symptoms of scurvy appear after about 1 month of a vitamin C-deficient diet and include bleeding gums, loose teeth, wounds that fail to heal, swollen ankles and wrists, bone pain and fractures, diarrhea, weakness, and depression 313
Remoldeling
bone _____________, the breakdown of older bone tissue and the formation of new bone tissue, occurs throughout adulthood; ________ also occurs during fracture repair, and it strengthens bone regions that are exposed to higher physical stress; cortical and trabecular bones differ in their rate of ___________; trabecular bone has a faster turnover rate than cortical bone 316
Platelets
cell fragments that assist in the formation of blood clots nad help stop bleeding
Osteoclasts
cells that erode the surface of bones by secreting enzymes nad acids that dig grooves into the bone matrix
Osteoblasts
cells that prompt the formation of new bone matrix by laying down the collagen containing component of bone, which is then minzeralized
hemochromatosis
consuming excessive doses of vitamin C can be harmful to poeple with a disease called _________, which causes an excess accumulation of iron in the body and leads to tissue damage and a heart attack 314
microcytic anemia
low iron, copper, and vitamin B6 cause ______________; small red blood cells 307
Meat factor
meat, fish, and poultry also contain a special _________, which enhances the absorption of non-heme iron; in contrast, all of hte iron found in plant based foods in non-heme iron, and no absorption-enhancing factor is present 304
Osteoblasts
new bone is formed through the action of cells called ________ or bone builders; these cells work to synthesize new bone matrix by laying down the collagen containing organic component of bone; within this substance, the hydroxyapatite crystallizes and packs together to create new bone where it is needed
modifiable risk factors of osteoporosis
smoking, low body weight, low calicum intake, low sun exposure, alcohol abuse, amenorrhea in women with inadequate nutrition, estrogen deficiency, testosterone deficiency, repeated falls, sedentary lifestyle 336
iron toxicity
symptoms include nausea, vomiting, diarrhea, dizziness, confusion, and rapid heartbeat; if _______ is not treated quickly, isgnificant damage to the heart, CNS, liver, and kidneys can result in death 306
Megadose
taking a _________ of vitamin C is not fatally harmful; however, side effects of doses exceeding 2000 mg/day for prolonged periods include nausea, diarrhea, nosebleeds, and abdominal cramps 314
RDA for zinc
the ____________ for men is 11 mg/ day and for women is 8 mg/ day 309
blood
the circulation of __________ is critical to life because it transports oxygen and nutrients to our cells, and removes carbon dioxide and other waste products generated from metabolism 303
Bone density
the degree of compactness of bone tissue, reflecting the strength fo the bones 316
Bioavailability
the degree to which the body can absorb and utilize any given nutrient 305
Plasma
the fluid portion of the blood; needed to maintain adequate blood volume so that the blood can flow easily throughout our body
Non heme iron
the form of iron that is not part of hemoglobin or myoglobin; found in animal and plant based foods 304
Heme
the hemoglobin molecule has four polypeptide chains, each with an iron-containing ________ group 303
Heme
the iron containing molecule in hemoglobin 303
Hemoglobin
the oxygen-carrying protein found in our red blood cells; almost 2/3 of all the iron in our body is found in ______ 303
Calcitirol
the primary active form of vitamin D in the body
Resorption
the process by which the surface of bone is broken down by cells called osteoclasts 316
Resorption
the process of remodeling invovles two steps: _________ and formation; bone is broken down through _________
Erythrocytes
the red blood cells, which are the cells that transport oxygen in our blood
1%
the remaining __________ of calcium in our body is found in the blood nad soft tissues
Hypermagnesmia
there are no known toxicity symptoms related to consuming excess magnesium in the diet; the toxicity symptoms that result from pharmacologic use of magnesium include diarrhea, nausea, and abdominal cramps; in extreme cases, large doses can result in acid-based imbalances, massive dehydration, cardiac arrest, and death; high blood magnesium levels, or _______________ occur in individuals with impaired kidney function who consume large amounts of nondietary magnesium, such as antacids
bone growth
through the process of __________, the size of bones increases; the first period of rapid ___________ is from borth to age 2, but growth continues in spurts throughout childhood and into adolescence; most girls reach their full adult height by the age of 18, with most boys continuing to grow up to the age of 21 316
macrocytic anemia
a form of anemia manifested as the production of larger than normal red blood cells containing insufficient hemoglobin; also callsed megaloblastic anemia 307
Iron deficiency anemia
a form of anemia that results from severe iron deficiency 307
Parathyroid hormone
a hormone secreted by the parathyroid gland when blood calcium levels fall; it increases blood calcium levels by stimulating the activation of vitamin D, increasing reabsorption of calcium form the kidneys, and stimulating osteoclasts to break down bone
Megadose
a nutrient dose that is 10 or more times than the recommended amount 314
calcitonin
a pharmacologic preparation of a hormone produced by the thyroid gland, which can reduce the rate of bone loss 339
Trabecular bone
a porous bone tissue that makes up only 20% of our skeletons and is found within the ends of the long bones, inside the simal vertebrae, inside the flat bones, and inside the bones of the pelvis 316
Collagen
a protein that forms strong fibers in the matrix of bone, blood vessels, and other connective tissues 312
Meat factor
a special factor found in meat, fish, and poultry that enhances the absorption of non heme iron 304
Prooxidant
a substance that promotes oxidation and oxidative cell and tissue damage 303
Osteomalacia
a vitamin D deficiency disease in adults, in which bones become weak and prone to fractures
Rickets
a vitamin D deficiency disease in children; signs include deformities of the skeleton, such as bowed legs and knocked knees; severe ________ can be fatal
Dual energy x ray absorptiometry
currently, the most accurate tool for measuring bone density
macrocytic anemia
the resulting condition of a folate or vitamin B12 deficency is sometimes called megaloblastic anemia but is more commonly called ______________ 310
Iron deficiency
the second stage of ___________ causes a decrease in the transport of iron and the production of heme, leading to symptoms of reduced work capacity; the final stage of __________- is true anemia 306
anemia
the term _______ means withou blood; it is used to refer to any condition in which hemoglobin levels are low; some __________ are inherited disorders 307
iron
the trace mineral __________ plays the leading role in enabling blood cells to transport oxygen 303
Remoldeling
the two step process by which bone tissue is recycled; includes the breakdown of existing bone and the formation of new bone 316
Leukocytes
the white blood cells, which protect us form infection and illness
True
True or false? Copper deficiency can result in accumulation of iron in the body
False
True or false? Our body can absorb vitamin D from sunlight
macrocytic anemia
inadequate intakes of folate or vitamin B12 cause ___________ 307
Heme iron
iron that is a part of hemoglobin and myoglobin; found only in animal-based foods, such as meat, fish, and poultry 304
Iron deficiency anemia
Abnormally small red blood cells are characteristic of
T score
a comparison of an individual's bone density to the average peak bone density of a 30 year old healthy adult
Hypocalcemia
a condition characterized by an abnormally low concentration of calcium in the blood
Hypomagnesmia
a condition characterized by an abnormally low concentration of magnesium in the blood
Hypercalcemia
a condition marked by an abnormally high concentration of calcium in the blood
Hypermagnesmia
a condition marked by an abnormally high concentration of magnesium in the blood
Fluorosis
a condition, makred by staining and pitting of the teeth, caused by an abnormally high intake of fluoride
Cortical bone
a dense bone tissue that makes up the outer surface of all bones as well as the entirety of most small bones of the body 316
Osteoporosis
a disease characterized by low bone mass and deterioration of bone tissue, leading to increased bone fragility and fracture risk 335
stomach acid
adequate amounts of stomach acid are necessary for iron absorption; people with low levels of stomach acid have a decreased ability ot absorb iron; this population includes many older adults and people who take medications that inhibit stomach acid production 304
Scurvy
adequate intake of vitamin C prevents __________ because it is critical to the synthesis of collagen; vitamin C acts as a coenzyme to specific enzymes that are required to convert collagen's precursor, procollagen, to collagen 312
Bone density
although the size and shape of our bones do not change signfiantly after puberty, our _____________, or the compactness of our bones, continues to develop into early adulthood 316
Myoglobin
an iron containing protein similar to hemoglobin except that it is found in muscle cells 303
Magnesium
__________ is a critical cofactor for more than 300 enzyme systems; it is necessary for the productio nof ATP, and it plays an important role in DNA and protein synthesis and repair; _________ supplementation has been shown to improve insulin sensitivity, and there is epidemiologcial evidence that a high magnesium intake is associated with a decrease in the risk for colorectal cancer; ______________ supports normal vitamin D metabolism and action is necessary for normal muscle contraction and blood clotting 323
thalassemia
__________ is a gnetic disorder in which red blood cells are small and short lived 307
Heme iron
__________ is a part of hemoglobin and myoglobin and is found only in animal based foods, such as meat, fish, and poultry; ____________ is more absorbable than non-heme iron; the iron in animal-based foods is about 40% ____________ 304
Hypocalcemia
__________ is an abnormally low level of calcium in the blood; _________ does not result from consuming too little dietary calcium but is caused by various diseases, including kidney disease, vitamin D deficiency, and diseases that inhibit the production of PTH; symptoms include muscle spasms and convulsions
Scurvy
__________ is thought to have caused more than half of the deaths that occurred on sea voyages centirues ago; during long votages, the crew ate all of the fruits and vegetables early in the trip, then had only grain and animal products available until they reached land to resupply 312
Iron deficiency
__________ progresses in stages, beginning with depletion of iron stores; during this first stage, there are generaly no physical symptoms because hemoglobin levels are not yet affected; 306
hemorrhagic anemias
__________ result from blood loss 307
Erythrocytes
__________, or red blood cells are the cells that transport oxygen 302
Leukocytes
__________, or white blood cells, are the key to our immune function; they defend against infection and the progression of cancer 302
bisphosphonates
__________, such as alendorate, which decrease bone loss and can increase bone density nad reduce the risk for spinal and nonspinal fractures; however, tehy do not appear to reduce the risk for a postmeonpausal woman's first ostepoorotic fracture, suggesting these medications may not be effective for primary prevention of fractures in postmeonpausal women
Platelets
___________ are cell fragments that assist in the formation of blood clots and help stop bleeding 302
vitamin C deficiencies
___________ are rare in developed countries but can occur in developing countries; scurvy is the most common ____-_______; anemia can also result form ___-________; people most at risk are those who eat few fruits and vegetables, including impvoerished or homebound individuals, and people who abuse alcohol and drugs 314
vitamin C
___________ in plant foods may enhance the absorption of non-heme iron in the food 304
Collagen
___________ is a fibrous protein present in the matrix of connective tissues; the most abundant protein in the body, it provides structure to bone, teeth, skin, tendons, and blood vessels, and many other tissues and organs 312
Sickle cell anemia
___________ is a genetic disorder in which the red blood cells have a sicke or half-moon shape 307
peak bone density
___________ is the point at which our bones are strongest because they are their highest density; the following factors are associated with a lower _____________: late pubertal age, inadequate calcium intake, low body weight, physical inactivity during adolesence 316
bone modeling
___________ is the process by which hte shape of our bones is determined, form the round pebble bones that make up our wrists to the uniquely shaped bones of our face, to the long bones of our arms and legs 316
Plasma
___________ is the watery matrix of blood in which the cells and platelets flow 303
Trabecular bone
___________ makes up 20% of the skeleton; it is found within the ends of the long bones, the spinal vertebrae, the sternum, the ribs, most bones of the skull, and the pelvis; ____________ is sometimes referred to as spongy bone because to the naked eye it looks like a sponge with cavities and no clear organization 316
selective estrogen receptor modulators
___________, such as raloxifene, which have an estrogen like effect on bone tissue, slowing the rate of bone loss and cprompting some increase in bone mass 339
vitamin K
____________ is a fat soluble vitamin important for a number of metabolic functions, including functions involved in blood and bone health; research has also revealed roles for ____________ in inflammation, hormone regulation, and defense against cancer 311
Dual energy x ray absorptiometry
____________ is considered the most accurate assessment tool for measuring bone density; this method can measure the density of the bone mass over the entire body; the ________ procedure is simple, painless, and noninvasive, and it is considered to be of minimal risk; it takes just 15 to 30 minutes to complete; the person participating in the test is scanned fully clothed through the use of a very low level of X ray
Hypomagnesmia
____________, or low blood magnesium, results from magnesium deficiency; this condition may develop secondary to kidney disease, chronic diarrhea, or chronic alcohol abuse, or as a result of low dietary intake magnesium; low blood calcium levels are a side effect of ___________
megaloblasts
_____________ contain inadequate hemoglobin; thus, their ability to transport oxygen is diminished; symptoms of macrocytic anemia are therefore similar to those of other types of anemia, and include weakness, fatigue, difficulty concentrating, irritability, headache, shortness of breath, and reduced exercise tolerance 310
Non heme iron
_____________, which is not a part of hemoglobin or myoglobin, is found in both plant-based and animal-based foods; ________ is not as absorbable as heme iron; since the iron in animal-based foods is about 60% non-heme iron, animal-based foods are good sources of absorbable iron 304
Fluorosis
consuming too much fluoride increases the protein content of tooth enamel, resulting in a condition called _____-___; because increased protein makes the enamel more proous, the teeth beocme stained and pitted; teeth seem to be at higher risk for ________ during the first 8 years of life, when the permanent teeth are developing; to reduce the risk for _________, children shold not swallow oral care products that are ment for topical use only, and children under 6 years should be superivsed while using fluoride containing products
megaloblasts
deficiency of either folate or vitamin B12 can impair DNA synthesis, which decreases the ability of blood cells to divide; if they cannot divide, differentiate, and mature, the cells remain large nad immature precursors to RBCs, knwon as _______________ 310
Osteoclasts
during resorption, cells called _____________ erode the bone surface by secreting enzymes and acids that dig grooves into bone matrix
fluorohydroxapatite
during the development of both baby and permanent teeth, fluoride combines with calcium and phosphorus to form __________, which is more resistatn to destructio nby acids and bacteria than is hydroxyapatite; even after all of our permanent teeth are in, treating them with fluoride, whether at the dentist's office or by using fluridated toothpase, gives them ore protection against cavities tha nteeth that have not been treated 325
the type of iron in the foods you eat
foods have two types of rion: heme iron and non-heme iron; heme iron is more absorbable than non-heme iron; since the iron in animal-based foods is about 40% heme iron and 60% non-heme iron, animal based foods are good sources of absorbable iron 304
.3-.5%
how much bone mass is lost every year after the age of 30
structural function of zinc
if proteins lose their shape, they lose their function; zinc helps to stabilize the structure of proteins involved in gene expression, vision, antioxidant enzyme systems, and immune function; in fact, zinc has received so much attention for its contribution to immune health that zinc lozenges have been formulated to fight the common cold 308
Iron deficiency anemia
in ______________, the RBC produced are smaller than normal, with low hemoglobin, and therefore cannot transport adequte oxygen; as a result, the body produces less energy, and the classic symptoms of ___________ occur; these include impaired work performance and neurological function, general fatigue, pale skin, and depressed immune function 307
Calcium toxicity
in general, consuming too much calcium from foods does not lead to toxicity in healthy individuals; much of the excess calcium we consume is excreted in the feces; however, an excessive intake of calcium from supplements can lead to health problems; consuming too much calcium can interfere with the absorption of other minerals, including iron, zinc, and magnesium and lead to various mineral imbalances; this may only be of major concern in individuals vulnerable to mineral imbalance, such as the elderly and people who consume very low amounts of minerals in their diets 322
hemochromatosis
in the US, 1 in 200 to 500 people suffer from a hereditary disorder called ______________, which causes excessive dietary iron absorption; because the body has no mechanism for eliminating excess iron, iron accumulates in body tissues, causing organ damage and other diseases; treatment includes restricting dietary iron intake, avoiding high intakes of vitamin C, and occasionally withdrawing blood 306
Other dietary factors
iron absorption is reduced from foods containing phytates, including legumes, rice, and whole grains; polyphenosls in tea, coffee, and red wine also reduce iron absorption, as do soybean, protein, and calcium 304
Hemoglobin
iron is a component of numerous proteins in the body; almost 2/3 of all the iron in the body is found in ___________, the oxygen carrying protein in our red blood cells; the __________ has four polypeptide chains, each with an iron containing heme group 303
Myoglobin
iron is also a component of ___________, a protein similar to hemoglobin but found in muscle cells; as part of _________, iron assists in the transport of oxygen into muscle cells 303
cytochromes
iron is also found in enzymes called ___________ that are active in the metabolism of carbohydrates, fats, and proteins; in the mitochondria alone, more than 12 of these iron-requiring enzymes help produce energy 303
Prooxidant
iron is part of an antioxidant enzyme system that assists in fighting free radicals; interestingly, excess iron can also act as a ____________ and promote the production of free radicals 303
Osteoporosis
of the many disorders associated with poor bone health, the most prevalent in the US is __________, a disease characterized by low bone mass; the bone tissue of a person with _________ deteriorates over time, becoming thinner and more porous than that of a person with healthy bone; these structural changes weaken the bone, leading to a sigifnicantly reduced ability of the bone to bear weight; this greatly increases the person's risk for a fracture; in the US, more than 2 million fractures each year are attributed to ____________ 335
nonmodifiable risk factors of osteoporosis
older age, caucasian or asian race, history of fractures as an adult, family history, gender, history of amenorrhea in women with no recognizable cause 336
kyphosis/ dowager's' hump
osteoporsis of the spine also causes a generalized compression fracutres in the vertebrae of the upper back lead to a shortening and hunching of the spine called _________, commonly referred to as _______________; the changes that _______ causes in the structure of the rib cage can impair breathing; moreover, back pain form collapsed or fracuted vertebrae can be severe
anemia
other ___________ are due to micronutrient deficiencies; these can be classified according to the general way they alter the size and shape of the RBCs 307
500-1500 mg
our body contains relatively little iron; men have __________ mg of iron in their body 303
300-1000 mg
our body contains relatively little iron; women have ____________ mg of iron in their body 303
the amount of iron in the diet
people who consume low levels of dietary iron absorb more iron from their foods than people with higher dietary iron intakes 304
Calcitirol
provitamin D3 travels to the kidneys, where it is converted into ___________, which is considered the primary active form of vitamin D in our body; ___________ then circulates to various parts of the body, performing its many functions; excess ___________ can also be stored in adipose tissue for later use