Exam 4
MFP factor
D. Enhances non-heme iron absorption
The risk for osteopersosis..
E. A, B, C are all true. (A. is higher in women) (B. increases in women who are postmenopausal). (C. is higher in underweight individuals)
14. Whicih statemen tis TRUE concerning lactation in women? Mark E if C and D are both true
E. Both C and D are true C = slow weight loss by lactating women neither compromises quantity of breast milk nor quality of breast milk. D = prevalence of breastfeeding has increased since the 1970s.
12. To avoid listeriosis during pregnancy, women should avoid unpasteurized milk and undercooked eggs and meats
A. true
Basics of the Functioning Nephron
1. Filtration. blood flowing through capillaries is filtered by glomerulus. Electrolytes, water, and urea are filtered into the tubules of the nephron. For adults, about 180 liters of water are filtered each day. 2. Reabsorption. as needed, water and electrolytes are reabsorbed back into blood by the actions of osmosis and membrane pumps. Usually 99% of water is reabsorbed. Hormones regulate membrane pumps capable of electrolyte reabsorption and water reabsorption 3. Excretion. excess water, urea, and electrolytes travel through nephron tubules to the bladder and are excreted via urine.
Risk factors associated w Neural Tube Defect
1. race, more common amongst whites and hispanics 2. previous pregnancy increases risk of second neural tube defect baby 3. maternal diabetes 4. maternal obesity 5. maternal anti seizure medication 6. exposure to hot temps early in pregnancy
Feeding Young Children
3 meals and 2-3 snacks per day. offer small portions. should be encouraged to listen to their hunger and fullness cues. parents should not overly coax children to eat. Tips: 1) plan reg meals and snacks w variety of foods from all food groups 2) be responsible for what/when to serve meals and snacks, let children be responsible for how much and whether to eat 3) be good role models. sit w children and eat same foods. 4) let children explore and enjoy food even when this means messes 5) keep mealtimes pleasant. 6) let children know what behaviors are expected and be consistent in encouraging good table manners 7) let children help w cooking, set up, clean up. 8) always be present while young children are eating to avoid choking.
15. Emily is 8 months old and has been consistently tracking at the 75th percentile for weight, this means that
A. 25% of US children are heavier than she is
Which statement(s) is(are) TRUE about sodium sensitivity?
A. A sodium sensitive person put on a low sodium diet will respond with a decrease in blood pressure
2. Qhat term is given to the time period which irreversible damage to the fetus may occur from specific events such as too little of an essential nutrient or exposure to toxins?
A. Critical period
10. Caffeine crosses the placenta
A. True
16. Which statement(s) is (are) false?
A. breast milk and infant formulas contain immune factors
6. A low birth infant is defined as a baby
A. of less than 5.5 pounds at birth
13. No safe amounts of alcohol consumption during all 9 months of pregnancy have been identified
A. true
Calcium Recommendations
An RDA for calcium has been established at 1,000 mg/day for men and women age 19-50 yrs, 1300 mg/day for children, and 1200 mg/day for adults older than 70 years. The UL for calcium is 2500 mg/d for adults 19-50 years old high sodium/high protein intakes can cause increased urinary loss of calcium. The 300 mg Rule: Milk and other dairy products such as yogurt and cheeses have the richest concentration of calcium. One cup (8 ounces) of milk, 1.5 ounces of cheese, or 1 cup of yogurt contain roughly 300 mg of calcium. Putting all other non-dairy foods together in most daily diets equals about 300 mg. Thus, for a child who need 1300 mg/day, at least 3 cups of milk or equivalent of other dairy foods is the best nutrition practice for them to develop peak bone mass. Bioavailability of Calcium: Plants are generally low in calcium content. Dairy avoiders or those with lactose intolerance can find a variety of food products which are fortified with calcium such as: soy milk, breakfast bars, orange juice, and tofu.
Nutrient Needs and Physical Activity during Lactation
Approximately 500 kcals/day above regular energy needs is necessary to supply the energy to produce the typical 25 ounces of breast milk per day. However, 330 kcals extra per day is recommended so that women slowly utilize the extra body fat accumulated during pregnancy. Moderate weight reduction is safe for breastfeeding women and does not compromise weight gain of the nursing infant. In most cases, nutrient inadequacies reduce the quantity, but not the quality of milk produced. lactating women should drink water and beverages throughout the day to avoid dehydration. A general guideline is for lactating women to drink about 3 liters of fluids per day
The optimal level of fluoride in water to minimize cavities with no adverse effects is
B. 1 ppm
18. At what age should the first semi-solid food be offered to infants?
B. 4-6 months of age
11. Modest intakes of beverages with caffeine, ie. 1 cup of coffee per day is discouraged by health professionals because of its potential teratogenic effects?
B. False
7. Which statement(s) is(are) FALSE about low birth weight infants?
B. Prevalance of low birth weight is lower in the African American population than the Hispanic population in the US.
3. Vitamins designed for pregnant women do not contain preformed vitamin A because
B. Retinoids are toxic to the developing embryo and/or fetus.
Blood levels of calcium
Blood calcium levels are affected little by dietary intake since bone can easily release calcium when blood levels are low, kidney and intestine can adjust when calcium intake is high. highly regulated because the processes mentioned above would go haywire if blood calcium levels went too high/too low. Thus, there is tight regulation of blood calcium levels by hormones
Breast milk and immune factors
Breast milk provides optimal nutrition for the infant. However, proteins such as the immune factors listed below as well as white blood cells cannot remain viable after processing of formula (to mimic breast milk), so are not part of its composition. Colostrum: watery milk substance produced by mother during 1st few days after delivery. rich in antibodies and white blood cells. mature breast milk continues providing immunological benefits protecting infant from disease causing bacteria for months after birth. other protective factors include: Bifidus Factors: favor of the growth of "friendly" bacteria in the GI tract Lactoferrin: binds iron in breast milk, preventing growth of iron dependent bacteria in GI tract and increasing bioavailability of iron for absorption Growth factors: stimulates development of a healthy GI tarct Lipase enzymes: helps protect against additional infections
4.Tanya has a BMI of 23 and just heard she was pregnant. The nurse practitioner tells her that a good weight range to gain in her pregnancy is
C. 25 to 35 pounds
20. When is it recommended that infants switch from breast milk or formulat to consuming some form of cow's milk
C. At 12 months of age
9. In terms of calcium nutrition during pregnancy
C. Calcium absorption increases
1. From 2 weeks to 8 weeks post fertilization, the ____ initiates the development of the placenta and amniotic sac
C. Embryo
19. It is recommended that young children limit their milk consumption to 2-3 cups per day. The reason for this limitation is because...
C. milk displaces other nutrient-dense foods that can lead to milk anemia.
Placenta (sometimes called afterbirth)
Essential to embryo and all future development. Metabolically active organ producing hormones that regulate fetal growth and maternal support tissue. Normal Placenta: provides a blood supply between mother and fetus. Key for healthy growth of a child. Abruptio Placentae: Placenta that doesn't keep its integrity Placenta Previa: placenta that forms in the lower uterus, increasing risk for hemorrhaging during last trimester.
hypothalamus
a brain center that controls activities such as maintenance of water balance, regulation of body temp, and control of appetite. kidney maintains water balance from hypothalamus along with hormones.
Iodine in food
abundant in seafood and present in soil near the ocean. soil content determines iodine amount present in plants/animals that graze on local plants. iodized salt, introduced in 1930s, eliminated deficiency.
Protein Pump System
also known as active transport. moves sodium cations and potassium cations across cell membranes as needed.
metabolic water
water generated during metabolism.
Iron Deficiency Anemia
a microcytic hypochromic anemia (small cell, low color) that results from depleted iron stores, depleted iron transport and reduced production of hemoglobin. The most commonly used biochemical measures of iron deficiency are blood hemoglobin and hematocrit (also called packed red blood cell volume). results in fatigue, weakness, or headaches when physically stressed. Other symptoms include apathy and poor resistance to cold.
fetal alcohol spectrum disorder (FASD)
alcohol exposure even at modest amounts may produce this. resulting in a variety of physical, behavioral (mood disorders), and cognitive (learning difficulties) abnormalities.
Juice
avoid introduction of juice until child can use cup. excess juice leads to diarrhea or intestinal upset. American Academy of Pediatrics limits juice to less than 4-6 ounces/day for children 1-6 yrs old.
dehydration
body output exceeds water input. symptoms include thirsty, dry skin, mucous membranes, rapid heartbeat, low blood pressure, weakness. also leads to electrolyte imbalance. A good general guideline is for elders to drink 6+ glasses of water or other beverage each day. elders are susceptible to dehydration because: 1. as we age, total body water decreases. elders have lower reserve of water. 2. elderly may no longer have sensitivity to thirst 3. older adults may be voluntarily reducing fluid intake due to problems w frequent urination 4. mile fever or during a hot, humid summer heat, elders critically lose body water
Extracellular fluid
fluid outside of cells. includes 2 main components - interstitial fluid between cells and intravascular fluid inside blood vessels. accounts for approx 1/3 of body's water. mainly sodium cations and chloride anions.
Copper (Cu)
found in enzymes that affect hemoglobin formation, act as an antioxidant, and are involved in energy metabolism. part of the enzyme superoxide dismutase - very important in reducing free radical formation. deficiency is rare but chronic levels of zinc could depress copper absorption.
hard water, soft water, bottled water
hard water: high in calcium and magnesium soft water: high in sodium or potassium bottled water: drinking water
Antidiuretic Hormone (ADH). also called vasopressin
hormone produced by pituitary gland in response to dehydration that stimulates kidneys to reabsorb more water and excrete less. elevates blood pressure.
Fluoride
important role in bones and teeth. 1) replaces hydroxyl group in hydroxyapatite (crystalline structure in bones and teeth) and forms even stronger and harder fluorapatite. 2) increases rates of re-mineralization. 3) acts as an antibacterial agent in saliva. while teeth are developing, too much fluoride causes discoloration known as fluorosis and can produce pitting on tooth surface. those with this have low rates of dental caries but teeth look unhealthy. drinking fluoridated water is the best sourcde of fluoride in most areas. fluoridation of public water supply (0.7-1.2ppm) has lowered incidence of decayed and missing teeth. areas where this is missing, pediatricians recommend fluoride pills for infants 6+ months of age.
Excess Retinoid Exposure
long known to be potent teratogens, causing severe birth defects esp if exposed during 1st trimester. UL of 3000 mg/day, which is only 4x the RDA for preformed vitamin A.
obligatory water excretion (loss)
minimum about 500 milliliters (about 2 cups) of water each day disposed of its wastes
Osmosis
movement of water across membrane toward side where solutes are more concentrated
Chromium (Cr)
notable for its role in carbohydrate and lipid metabolism. helps maintain glucose levels by enhancing insulin activity. deficiency is characterized by diabetes like symptoms. abundant in unredefined foods, meats, cheeses, grains.
Sulfur (S)
present in every cell because it's a component of the amino acids, methionine, cystine, and cysteine and other organic molecules. Sulfur is found in abundance in hair, skin, and nails. There is no RDA for sulfur because sulfur alone is not required, but rather, the organic molecules to which it is a part.
Selenium (Se)
present in the enzyme, glutathione peroxidase, where (along with vitamin E and other antioxidants) block formation of free radicals. deficiency is rare but documented in china (Keshan disease) Selenium Supplement Claims: researchers are leery of selenium supplements since it can be toxic and may do more harm in terms of chronic diseases.
Water Balance
the balance between water intake and output (losses).
Breastfeeding benefits:
FOR MOMS: 1. contracts uterus to prepregnancy size more quickly. 2. delays ovulation. (However, this is not a guarantee infertility. Other birth control should be used to prevent conception.) 3. delays menstruation, thus iron is conserved. 4. may protect against breast and ovarian cancer. 5. cheaper than purchasing formula. 6. environmental savings in the manufacturing, packaging, and shipping of formula. The Healthy People 2010 goal in the U.S. is that 75% of women leaving the hospital should be breastfeeding and 50% still breastfeeding at 6 months FOR INFANTS: 1. Breast milk provides the appropriate composition of nutrients and at high bioavailability for infants. 2. Breast milk contains immune factors (see below) and thus reduces risk for GI infections. 3. For infants that are prone to allergies, there is reduced risk for some of them. 4. Breast milk contains long chain fatty acids (DHA and EPA) for brain and vision development. Formula can now be purchased with these long chain fatty acids. 5. Infants are exposed to different flavors through breast milk and thus may try a greater variety of foods as toddlers. 6. Breast-fed infants grow at a slightly, but significantly slower rate than formula fed infants; there is some limited evidence that breast-fed infants may be at lower risk for adult obesity. 7. There is some evidence that breast-fed infants have reduced risk for some chronic diseases as adults, such as heart disease.
Nutrient Needs of Infants
Fat, Protein, Minerals: breast milk and formula are low in protein and high in fat. fat helps provide high energy required during 1st year of life. infant's kidneys cannot handle protein level in cow's milk and cause excess urea production. balance of minerals such as calcium and phosphorus in breastmilk is just right for infant, whereas cow's milk is very high in major minerals and would stress the kidney. iron: healthy infants are born with high levels of ironstores. adequate iron stores for first 6 months of life. after 6 months, iron fortified cereals, pureed meat, or iron supplements are important to maintain healthy iron status. fluoride: breast milk is poor in fluoride. after 6 months, infant should be supplemented with fluoride via drinking water. Vitamins: all US born infants are injected with Vitamin K before leaving hospital to protect against hemorrhagic disease of the newborn, a rare disease that can cuase bleeding to death. breast-fed infants require a vitamin D supplement. rickets has recently appeared as an issue in some breast-fed infants who are from ethnic groups w darker skin or little exposure to sunlight. a vegan/vegetarian mother is at risk of low vitamin B12 status. supplementation is prudent.
What is the role of sugar in ORT?
Glucose uses sodium as a cotransporter so sodium and water enters the body this way
Iron Overload Disorder
Hereditary iron overload or hemochromatosis is the most common genetic disorder in the United States, affecting some 1.5 million people. It may take years for these individuals to become symptomatic. More men than women have been diagnosed since women lose iron by menstruation. Because too much iron gets into the body, iron overload disorder can cause liver damage, apathy, lethargy, and fatigue. Note that these latter symptoms can be confused with iron deficiency, therefore self medicating with iron supplements without a medical diagnosis of iron deficiency anemia is unwise.
Neural Tube Defects and Folate
High intakes of folic acid during early stages of pregnancy reduce occurrence of neural tube defect. Spina Bifida: the most common neural tube defect. neural tube fails to close and spinal cord isn't completely protected by normal development of bones in spine. can be irreparably damaged leading to paralysis. The most serious neural tube defect causes incomplete brain development (anencephaly) and results in miscarriage or death soon after birth.E
Fortification
In 1938, the U.S. mandated the fortification of many grain products with iron, such as flour. One slice of bread has about 10% of the RDA for men and postmenopausal women, while only 5% of the RDA for premenopausal women. Since Americans eat diets rich in grain products, they are a significant source of iron.
Iodine
Iodine as IODIDE is part of the structure of the thyrode hormone, Thyroxine, which controls basal metabolic rate, body temp, growth, reproduction, muscle function, and energy metabolism. An iodine deficiency leads to decreased production of active thyroxine. The body increases thyroid stimulation hormone to make more, causing cells of thyrode gland to enlarge. enlargement is visible in neck (simple goiter). deficiency left untreated causes sluggishness, weight gain (adults). for children it results in poor cognitive functioning. during pregnancy, it causes severe mental and physical retardation (crentinism).
Iron Poisoning
Many cases of iron poisoning are reported every year due to young children accidentally overdosing on their mother's iron supplements, mistaking them for children's vitamins. As little as 200 mg, which could be just 5 pills, can cause death in a young child. Iron tablets and all other dietary supplements should be stored out of the reach of children.
The First 12 Months
Parents may breastfeed for 1st year, formula feed, or feed in a combination as primary source of nutrition. Feed on demand (2-4 hours). At 4-6 months of age, solid foods (semisolid) should be introduced to provide additional energy and nutrients. iron fortified rice cereal is usually the first introduction. pureed meats are also rich in iron. pureed fruits and veggies. At 8-9 months, infant is ready for small pieces of soft table foods. Infant Formula as alternative: must be consistently available, properly prepared, stored. uncontaminated water must be used for mixing. No honey - risk of botulism. Avoid: regular canned veggies (excess salt), concentrated sweets (excess calories), strong spices or sugar alcohols. Choking hazards: whole grapes, whole beans, hot dogs, etc.
Infant Nutrition
Plotting the pattern of growth is the first way to assess nutritional status in infants (0-1 year of age), and for children, too. The Center for Disease Control (CDC) supplies national growth charts for health professionals and parents to carefully plot the growth of infants and children in weight and height for age. A healthy infant doubles her birthweight during the first 5 months and triples birthweight by one year.
Milk (Early childhood)
Starting at 12 months - 2 yrs, current recommendation is to offer whole milk instead of formula/breast milk. 2-3 cups per day. chronic consumption of milk can lead to milk anemia. iron deficiency can occur if there's too much milk consumed - displaces foods w iron. known to affect behavior, attention span, and learning.
fetal alcohol syndrome (FAS)
The most severe case of irreversible mental and physical retardation of embryo and fetus.
Maternal Nutrition
Women who select nutrient-dense foods to meet their increased kcalories needs during pregnancy can easily meet their nutrient requirements. MyPlate is the best food guidance system to follow during pregnancy since it encourages balance, variety, and moderation. Although some pregnant women seem to crave certain foods, there is no scientific evidence that women are craving specific nutrients
5. Women who are overweight when starting their pregnancy
E. C and D are both true C = are at increased risk for neural tube defects D = have more labor and delivery complications
17. Why should a 3 month old infant never be fed cow's milk, ie. what we buy in the grocery store?
D. A and C are both true. A = infants cannot tolerate the high protein in cow's milk C = infants cannot tolerate the high content of calcium and phosphorus in cow's milk
8. In terms of iron nutrition during pregnancy
D. A, B, and C are all true. A = low iron status increases risk for low birth weight newborns B = iron recommendations are increased by 50% over pre-pregnancy RDA C = iron absorption increases.
Safe levels of fluoride in community water
0.1 ppm - increased incidence of dental carries and missing teeth 0.7 ppm - optimal dental health (apr 2015 HHS proposed recommendation of 0.7) 8 ppm - increased incidence of fluorosis.
Regulation of Water and Sodium Balance (recover from dehydration)
1. As dehydration worsens, blood pressure and blood volume drop, rapid heart beat develops and general weakness occurs. 2. With blood volume drop, blood is concentrated w sodium, which signals hypothalamus to stimulate pituitary glands (in brain) to release hormone anti-diuretic hormone (ADH). 3. ADH stimulates kidneys to reabsorb more water from nephron tubules back into blood to dilute blood sodium concentrate 4. dehydration can also reduce blood flow aka lower blood pressure. kidney responds by releasing the enzyme Renin into blood, which activates blood protein Angiotensinogen, converting it to Angiotensin. 5. Angiotensin signals adrenal glands to release hormone Aldosterone. Aldeosterone causes kidney to reabsorb sodium. Sodium and other electrolytes attract water. When sodium is retained or reabsorbed, water follows via osmosis and blood volume and blood pressure increase 6. Angiotensin is a powerful vasoconstrictor causing blood vessels to narrow which increases blood pressure 7. Water is reabsorbed back into body and blood pressure rises to prevent dehydration.
Risk Factors for LBW Infants
1. Inappropriately low maternal weight gain 2. Both younger and older mothers have increased risk of LBW. 3. Race: African Americans have highest risk for LBW. 4. Poor nutrition: Iron deficiency increases risk for LBW. 5. Smoking 6. Genetics 7. Prior health conditions 8. Low socioeconomic status 9. No or infrequent prenatal care 10. Alcohol or drug use LBW by Race: Black LBW by age: 45-54 LBW by smoking: smoker
Similarities & Differences of Major and Trace Minerals
1. Inorganic. Cannot be destroyed by heating, acid, or processing 2. Do not provide energy, but many are involved in energy metabolism as metalloenzymes (enzymes w a mineral component) or the storage of energy as ATP. 3. Some absorbed directly into blood and move freely in body, others require protein carriers and active transport mechanisms 4. Bioavailability can vary. Some organic compounds like phytic acid and oxalic acid found in plants bind w minerals forming insoluble compounds that can't be absorbed 5. Some minerals interact w each other altering bioavailability 6. Some minerals exist as ions dissolved in body fluids and as components of essential molecules or enzymes.
Functions of Iron
1. Iron has two common ionic states, Fe++ (ferrous iron, reduced) and Fe+++ (ferric iron, oxidized). Because it is able to accept electrons, iron is involved in many oxidation- reduction reactions, including the electron transport chain in the final production of ATP in the mitochondria. 2. Since iron has an affinity for oxygen (O2), iron-rich hemoglobin picks up O2 in the lungs and transports it via red blood cells to all parts of the body. 3. Myoglobin in muscle is another Fe-containing protein that binds O2. 4. Additionally, iron is important in brain and nervous tissue function since it is a cofactor necessary for the catalytic activity of enzymes responsible for the synthesis of several neurotransmitters.
Functions of Major Minerals
1. Maintaining water and acid-base balance and osmotic pressure 2. Part of metalloenzymes 3. Membrane transport of essential nutrients and other compounds 4. Maintaining nerve transmission and muscle contractions 5. Structural components (hydroxyapatite crystals of bone and teeth) 6. Components of organic molecules (P is part of DNA, RNA, ATP, Phospholipids. S is part of amino acids).
Two slices of turkey salami contains 610 mg of sodium. The nutrition facts label reads that the % DV for sodium is..
25%
The DASH Diet
A large clinical research trial called DASH (Dietary Approaches to Stop Hypertension) indicated that elevated blood pressure was reduced by a diet that emphasizes fruits, vegetables, and low-fat dairy foods and was low in saturated fat, total fat, and cholesterol. The food plan in the DASH trials was as effective as medication in treating mild hypertension. A second clinical trial called "DASH-Sodium," looked at the effect of reduced dietary sodium intake on blood pressure as people followed either the DASH diet or a typical American diet. The biggest blood pressure-lowering benefits were for those eating the DASH diet at the lowest sodium level (1,500 milligrams per day). The DASH diet includes whole grains, poultry, fish, legumes, and nuts and has reduced amounts of fats, red meats, sweets, and sugared beverages.
Beef is rich in ___ iron and this form of iron has ___ bioavailability than the iron in spinach
A. Heme, higher
Which statement is TRUE about zinc?
A. Zinc is stored in the intestinal cell as part of metallothionein
Which is the correct enzyme/mineral pair?
A. glutathione peroxidase/selenium
You have had an evening of modest yet responsible drinking of alcoholic beverages with friends. This caused inhibition of your antidiuretic hormone (ADH) and thus
A. inhibition of water reabsorption by your kidneys
Iron Requirements
Adult men require 8 mg/day of iron, whereas premenopausal women require more than twice that amount, 18 mg/day, since they lose iron via monthly menstruation. The UL for iron is set at 45 mg/day in a supplement. Pregnant women require 27 mg/day which may be difficult to get in diet, thus many physicians suggest iron supplements during pregnancy.
Magnesium (Mg)
Approx 60% of the body's magnesium is in bones and teeth. important in the formation of ATP in energy metabolism and also is part of hundreds of metalloenzymes. It acts antagonistically to Ca in muscle contraction: Ca stimulates, while Mg relaxes. Foods containing Mg are emphasized in the DASH diet because the balance between Ca and Mg helps maintain normal blood pressure. Mg is part of the chlorophyll molecule responsible for carbon fixation in green plants, therefore, are excellent sources of Mg. Mg is also found in meats, legumes, dairy products, and fruits. Though Mg is often low in the American diet, deficiency is rare, possibly because bone acts as a Mg bank.
A drop in blood sodium concentrations would result in which of the following responses?
B. A stimulation of aldosterone release
A classic sign of zinc deficiency is
B. growth retardation
Bone
Bone is a dynamic tissue. Osteoclasts: cells that hug the inner lining of the bone that constantly chew up bone Osteoblasts: build up bone structure During diff stages of the lifecycle, the ratio of activity of these cells vary. During childhood, the oseoblasts (build) are working harder than osteoclasts (chew), to build up net bone mass. In contrast, during the aging years after 40, osteoclast activity is elevated over osteoblast activity, resulting in a slow decline in bone density. The three major factors contributing to bone health are 1) dietary adequacy of Ca and vitamin D status, 2) weight bearing exercise, and 3) genetics.
For the typical American adult, the average daily loss of water via the kidney, lungs, feces, and skin is approximately...
C. 1.5 to 2.8 liters
What is the calcium RDA for young adults?
C. 1000 mg
Advice during pregnancy
Caffeine: 1 cup of coffee or 2 cups of cola is OK. any more can cause fetal damage. Alcohol: Alcohol consumption can lead to irreversible mental and physical retardation of the embryo and fetus. No safe amount of alcohol has been identified; therefore, women should drink no alcohol during pregnancy Mercury in fish: Some fatty fish contain high levels of mercury which can harm the brain and nervous system of the developing fetus. Avoid the following fish: shark, swordfish, king mackerel, and tilefish (also called golden snapper). Limit average weekly consumption to 12 ounces (cooked or canned) of seafood (including light tuna) or to 6 ounces (cooked or canned) of white, albacore tuna. Supplements of fish oil are not recommended due to risk of contaminants. Foodborne Illnesses: To avoid the foodborne illnesses such as listeriosis, pregnancy women should not eat or drink unpasteurized milk, milk products, or juices; raw or undercooked eggs, meat, or poultry; or raw sprouts. Pregnant women should only eat certain deli meats and frankfurters that have been reheated to steaming hot. Drugs and Herbal Supplements: Many prescription and illicit drugs cross the placenta and can cause pregnancy complications, serious birth defects, and infant death. Even herbal supplements should be taken only after consultation with a physician. Smoking: Smoking and chewing tobacco decrease oxygen and nutrient supplies to the fetus and interfere with waste removal. Numerous complications are linked with smoking during pregnancy including growth retardation, low birth weight, early separation of the placenta, spontaneous abortion, and fetal death. An infant exposed to second hand smoke is at increased risk of sudden infant death syndrome, middle ear infections, and respiratory and cardiac diseases.
Calcium (Ca)
Calcium is the most abundant mineral in the body; 99% is found in bones and teeth as hydroxyapatite crystals, and 1% is found in the blood and soft tissues as ionized calcium. The regulation of body fluid calcium concentrations is essential for maintaining physiological processes as muscle contraction, the transmission of nerve impulses, blood clotting, secretion of hormones, enzyme reactions, and blood pressure.
Parathyroid homrone (PTH) is released in response to low plasma calcium and along with ___ results in ___
D. Active vitamin D, decreased calcium out into urine
Which statement follows the principles of osmosis with biological membranes?
D. If sodium leaves the inside on the cell, then water follows it.
Ferroportin (also known as mucosal transferrin)
D. Takes iron from the intestinal cell and transfers it across the membrane into blood
Which statement is FALSE about these major minerals?
D. When you eat inorganic sulfer, enzymes in your body incorporate it into methionine.
Critical Periods
During early stages of embryonic development, in which an organ or organ system can be irreversibly affected by an adverse event (ex. alcohol, too little/much of essential nutrient). During the 1st 10 weeks after conception (cell differentiation and division is rapid).
Blood is filtered by glomerulus in the capsule of the of the nephron of a healthy adult. Next the fluid passes down the tubules of the nephron. What happens in the tubules? (Read all below for the best answer)
E. Both B and C are true. (B. Depending on the need, sodium is reabsorbed back into the body) (C. Depending on the need, potassium is reabsorbed back into the body).
Which statement(s) is(are) FALSE about iron status? If two of the statements are false, mark E
E. Both B and D are false (B. Hemochromatosis is caused by acute infections of the liver) (D. When iron is overabsorbed, then there is an increased excretion of iron in urine).
Folate
Eating foods rich in folate such as green leafy vegetables, legumes, orange juice and oranges, whole grains, and fortified grains is the best advice. If a physician is concerned about folate status, a prenatal vitamin supplement will be recommended.
Oral Rehydration Therapy
Electrolyte imbalance occurs when too much Na, CI, and K+ are lost through excessive vomitting, diarrhea, and sweating. In poor nations, children can die of hydration because water absorption in digestive tract is often shut down by bacterial infection. A simple solution of 1 cup of boiled water, a pinch of salt (NaCl), and 2 tsp. of sugar (sucrose) has successfully been used as an oral rehydration therapy (ORT) to restore electrolytes and reduce dehydration. The water is absorbed into the body via glucose's active transporter system (not affected by the infection) which has sodium as the cotransporter, thus dragging water along with it.
Major Minerals Also called macrominerals.
Essential mineral nutrients the human body requires in relatively large amounts. Greater than 5 GM. Na (sodium), K (potassium), Cl (chloride), Ca (Calcium), P (Phosphorus), Mg (Magnesium), S (Sulfate)
Trace Minerals Also called microminerals.
Essential mineral nutrients the human body requires in relatively small amounts. Less than 5 GM. Fe, Zn, I, Cu, Fl Iron, Zinc, Copper, Manganese, Iodine, Selenium
Ferritin, Ferroportin, Blood Transferrin, Hepcidin, Iron Excretion.
Ferritin: After iron is transported into the small intestinal cell, either as heme or nonheme iron, it is sequestered by a protein call ferritin. Ferritin has the capacity to temporarily store thousands of iron atoms. Ferritin is also the storage protein for iron in the liver. Ferroportin: If the body is in need of iron, then ferritin in intestinal cells releases iron, which then attaches to ferroportin. Ferroportin is a transport protein and it is associated with the membrane on the blood side of the intestinal cell (also called a mucosal cell). Blood Transferrin: Iron does not travel free in the blood. It is attached to the protein called blood transferrin, which delivers iron to the body tissues, for example, bone marrow for hemoglobin synthesis. Hepcidin: When the body has gotten enough iron, the liver secretes the hormone, hepcidin. Hepcidin blocks ferroportin from transferring iron into the blood. Follow the five steps animated shown above. Iron Excretion: Mucosal cells die at a high rate and are then shed into the intestinal lumen resulting in iron from ferritin being excreted in feces. This is an elegant system by which the body protects itself from the over accumulation of body iron; that is, if the body does not need iron, it remains in the intestine and is excreted. Extremely little iron can be excreted in urine since it is protein bound and proteins are not filtered out by the kidney. Women lose iron monthly via menstruation; thus, men and postmenopausal women are at higher risk for toxicity compared to premenopausal women.
Iron (Fe)
In poor/developing countries, as many as 30% -50% of young children and pregnant women have compromised health due to iron deficiency or iron-deficiency anemia. Even in the US where food is plentiful, iron deficiency is a health concern for toddlers, adolescent girls, and women in their childbearing years, esp those of low socioeconomic status. Integral part of the heme structure. this structure attracts oxygen as part of the iron-protein complex called hemoglobin. healthy red blood cells are rich in hemoglobin.
Ions, Cations, Anions
Ions: atoms or molecules that have gained or lost electrons, therefore have electrical charges cations: positively charged anions: negatively charged.
Food iron & iron absorption
Iron absorption: Iron embedded in a heme structure (from hemoglobin and myoglobin) is found only in foods of animal origin and has high bioavailability. In contrast, nonheme iron (as Fe++ or Fe+++) is found both in foods of animal origin and in foods of plant origin and has lower bioavailability than heme iron. Heme iron has higher bioavailability with 25% being absorbed. However, for a vegetarian who eats no animal foods, only about 10% of iron is absorbed. Overall in the mixed American diet, about 18% of iron is absorbed. The iron recommendation for vegetarians is 1.8 times the RDA to compensate for the significantly lower bioavailability of nonheme iron as the only source of dietary iron. 1. An MFP peptide factor found in meat, fish, and poultry enhances nonheme iron absorption. 2. Also research shows that vitamin C in a meal enhances nonheme iron absorption by keeping the form of iron in the reduced state. Note that supplements contain iron already in the reduced state so that vitamin C has no added benefit when consumed at the same time as a supplement. 3. In contrast, plant foods high in phytates and fibers such as in legumes, whole grains, and rice can reduce nonheme iron absorption in a meal by binding it causing increased excretion in the stool rather than absorption into the body. Of course these foods should not be avoided since they contain important essential nutrients and phytochemicals. A high fiber, vegetarian diet for children may not only be low in iron, but could cause increased iron excretion and thus increased risk for deficiency. A carefully chosen diet or supplements is important to maintain good iron status in a vegetarian child.
Iron
Iron is needed for an enlarged maternal blood volume and to provide for the needs of the placenta and infant. Additionally, more iron is required to replace inevitable blood loss during birth. Prenatal supplements are recommended for women with increased needs such as short spacing between pregnancies, teenage pregnancy, decreased energy intake, multiple fetuses (twins, triplets etc.), cigarette smokers, and alcohol or drug abusers, as well as for women known to have poor eating habits. Many obstetricians routinely advise iron supplements of about 30-60 mg/day to pregnant women just for insurance purposes.
Zinc Absorption and Regulation
Like iron, less than 40% of dietary zinc is absorbed into blood. And like iron, a mucosal cell protein temporarily stores zinc before further transport into blood. This intestinal storage protein for zinc is called metallothionein. Only when the body needs zinc will metallothionein release zinc for transport into blood. Zinc is transported in blood attached to a blood protein called albumin, however, blood transferrin can also transport zinc. Pancreatic secretions are rich in zinc, therefore, this is another way the body can get rid of it. Unabsorbed zinc from either diet or pancreatic secretions is excreted in feces.
Hypertension
Many people w hypertension are "salt sensitive." their kidneys are less efficient at removing excess sodium, therefore, they may experience hypertension w high sodium intake. dietary salt restriction closer to the AI helps lower blood pressure. Can cause physical damage to arteries (initiating atherosclerosis), enlargement of the heart resulting in heart failure, and ballooning and weakening of artery walls resulting in aneurysms (bursting of the artery wall) that may lead to blindness, stroke, or death. Approx 50 million Americans (~30% of the adult population) are affected by hypertension and about half of these are sodium sensitive. The Dietary Guidelines recommend a diet moderate in salt and sodium and thus recommends less than 2300 mg of sodium/day. This is equivalent to 6,000 mg or 6 g of salt, the equivalent of 1 tsp of table salt.
Potassium and Chloride
Potassium: major intracellular cation. important for electrolyte balance, nerve transmission, muscle contraction, maintaining blood pressure. Potassium is available in many fresh foods, especially fruits and vegetables. Potassium is also plentiful in milk and legumes; meats, chicken, and fish contribute modestly to the potassium in the American diet. AI is 4700 mg/day. Chloride: the major extracellular anion. It is important in maintaining fluid and electrolyte balance. As a component of hydrochloric acid (HCl), chloride functions in the stomach during initial digestion. Chloride is part of NaCl and is therefore abundant in the diet.
Reduce risks for Osteoporosis
Reach your genetic potential in terms of peak bone mass. Maintain a life time of physical activities. RISK FACTORS: Age Family History of Osteoporosis Race - Caucasian or East Asian Low dietary calcium and vitamin D deficiency Underweight (low BMI) Smoking Chronic Steroid use (asthma, rheumatoid arthritis Female Gender Sedentary Lifestyle Hormones (low estrogen and elevated thyroid) Anorexia or bulimia Alcohol consumption in excess Extreme underweight in women as seen in anorexia nervosa, bulimia nervosa, or excessive physical activity leads to decreased bone density through a different mechanism
Zinc Deficiency
Severe zinc deficiency is characterized by growth retardation and delayed sexual maturity in children and adolescents. Zinc deficiency was first characterized in a group of Egyptian boys during the 1960's whose all plant-based diet was high in fiber and phytates causing binding of zinc in the intestine. Unleavened breads which were a staple in their diet, does contain zinc, but it is unavailable for absorption since it is in a bound form. Scientists have since discovered that leavening by yeast releases the zinc in bread making it more bioavailable. In the US diet, red meat, whole grains, some fortified cereals, and milk are the richest sources of zinc. Severe zinc deficiency is no longer a threat around the world, however, in some populations, concern for subtle zinc deficiency may be contributing to enhanced infection rates or poor growth and development in children. The amount of fiber proposed by the Dietary Guidelines is not high enough to affect zinc status.
Reducing Sodium in your diet
Some tips for reducing sodium or salt from your diet include: 1. Add little/no salt to foods at the table. 2. Prepare foods w less salt by trying other sodium-free spices. 3. Select fresh/frozen vegetables or low-sodium canned varieties. 4. Cook w less salt. 5. Read food labels for high sodium DV's and look for lower sodium products. 6. Use less often/find alternate lower sodium varieties of high sodium foods and condiments such as: Processed meats, Pickles, olives and sauerkraut, Snack food with visible salt, ex. salted chips, pretzels, and popcorn, Canned soups and instant soups, soy sauce, BBQ sauces, catsup, Cheeses, especially processed varieties.
Sodium (Na)
The Adequate Intake (AI) for sodium is 1500 mg/d for younger adults and decreases to 1300 (51-70 years) and 1200 mg/d (>70 years) as adults age. The UL is 2300 mg/day. The DV for sodium on food labels is based on 2400 mg/d. The DV has not been changed to the new AI or UL because of cost to the food industry and because it is debatable as to the appropriate figure for a food label. The 1500 mg/d goal is difficult to achieve, plus is most appropriate for those with hypertension or at high risk for hypertension. the highest percentage of sodium in the diet comes from processed foods containing salt (NaCl) or other additives such as sodium bicarbonate, sodium saccharine, monosodium glutamate (MSG), and many others. NaCl is 40% Na.
Calcium and Vitamin D
The physiological changes during pregnancy adapt to the fetus's needs for calcium by increasing absorption and retention. Thus, the RDA for calcium is the same for pregnant and non-pregnant women. Because of toxicity risk, supplemental vitamin D above the RDA is not recommended. Eating a variety of milk, cheeses, yogurt, and calcium-rich foods during pregnancy assures adequacy of these bone-building nutrients.
Pregnancy and weight issues
Typical 40 week gestation produces infant weighing 6.5 - 8.75 pounds (range for healthy newborn with lowest risks of poor health). Contributing factors are maternal preconception weight and weight gain during pregnancy. Women who are underweight going into pregnancy are at risk for: smaller placenta, low birth weight infants (less than 5.5 pounds), and premature birth (less than 37 weeks) Women who are obese going into pregnancy are at risk for: maternal medical complications (hypertension, diabetes, postpartum infection), labor and delivery complications (large infant, birth trauma, cesarean section), poor development/infant death, neural tube defect.
Current recommendations for weight gain:
Underweight (BMI < 18.5): 28-40 pounds Healthy weight (BMI 18.5-24.9): 25-35 pounds Overweight (BMI 25-29.9): 15-25 pounds Obese (BMI ≥ 30): 11-20 pounds A reasonable estimate to achieve adequate weight gain for healthy-weight women is 340 kcal/day during the second trimester and 450 kcal/day for the third trimester. pregnant teens are supporting their own growth and development, tend to have poor diets and tend not to seek prenatal care. Therefore, recommendations are for them to gain on the high end of the ranges indicated above.
Zinc (Zn)
Zinc helps regulate immune function, thyroid function, as well as motor and cognitive development in children. Additionally, zinc has a role in vitamin A metabolism, taste, and wound healing.
Zinc, Iron and Copper Interactions
Zinc, iron, and copper have similar chemical characteristics, thus they can interact and compete in the body. Experts caution the over use of either zinc or iron supplements for the following reasons: 1. High iron absorption either from overload disorder or iron supplements can over saturate blood transferrin, leaving little room for the transport of zinc and resulting in reduced absorption of zinc. 2. Chronic use of zinc supplements can cause decreased absorption of iron or copper, again due to competition with transport. The UL for zinc has been established at 40 mg/day.
Phosphorus (P)
a component of hydroxyapatite, the crystalline structure also containing calcium that gives bones and teeth their strength. ATP contains high-energy phosphate bonds to store energy. Phosphorous is required in many enzyme reactions. It is a component of phospholipids involved in lipid transport and cell membranes, a part of DNA and RNA, and participates in acid-base balance as the intracellular anion HPO4-2. Phosphorus deficiency does not occur since it is found in many proteins (milk, meat, legumes) and is a component of many common additives used in processing.
Osteoporosis
a disease characterized by low bone mass and deterioration of bone tissue. the leading cause of fractures of hip, spine, and wrist in elder population. called the "silent disease," because habits throughout life span can increase risk, but usually not diagnosed until bone density becomes critical. major public health concern since it occurs in 1/5 adults between 65-74 and dramatically increases to 1/3 adults 75+ years old. can be very painful and a major cause of permanent disability. Multiple spine fractures cause a significant loss of height and a characteristic bending of the spine (Dowager's hump). Breathing/eating become hard because lungs/stomach are compressed into smaller space. Many people w fractures of the hip never walk/live independently again. 80% of those with osteoporosis are women. Men achieve a higher peak bone density than women. women on avg have lower stores and can lose up to 20% of bone mass during onset of menopause when estrogen levels drop. Estrogen has a positive effect on maintaining bone density. Estrogen replacement therapy for postmenopausal women has been very effective at reducing bone loss; however, estrogen therapy may increase risk of heart disease + breast cancer. risks and benefits associated with estrogen supplementation must be carefully considered.
water intoxication
body water contents are too high in all body fluid compartments. 10+ liters over a short period time is too much. symptoms include confusion, convulsions, and death due to hyponatremia.
Regulation of body iron
careful regulation of its absorption, transport, storage, recycling, and losses. Because ionized iron can cause havoc in free radical production, iron is always bound to specific proteins in tissues and fluids of the body. Iron binding proteins play critical roles in iron homeostasis. Step 1: inside the lumen of small intestine, iron from food is found in forms of heme or non-heme iron (Fe). Step 2: iron stored in intestinal mucosal cells attached to protein called ferritin. Step 3: when iron is needed, mucosal transferrin (now called ferroportin) facilitates absorption of iron to blood. blood transferrin picks up iron to transport to tissues. Step 4: if body has plenty of iron for physiological use and storage, liver excretes hormone "hepcidin". hepcidin blocks ferroportin from transferring iron into blood.
Folic Acid Fortification
critical period for embryonic folate exposure is 17-30 days. If woman has given birth to a baby with neural tube defect, she has to consume higher levels before and during next pregnancy. In 1998, FDA mandated processed grain products to be fortified with folic acid. This has decreased defects by 25%. RDA for pregnant women is 600 mg/day.
hyponatremia
decreased concentration of sodium in the blood through excessive sweating (exercise), vomiting, diarrhea. symptoms include muscle cramps, mental apathy, loss of appetite. consume ordinary food with water or simple salt-sugar water mixture (oral rehydration therapy), sports drinks containing electrolytes. salt tablets are not recommended.
Electrolytes and Kidney Function
electrolytes and other osmotic particles lie proteins are the major force of maintaining water compartments in body and regulating balance. A healthy kidney is v effective at maintaining balance as well as electrolyte balance by regulating the re-absorption or excretion of various electrolytes. Electrolytes require protein carriers (pumps).
Interstitial fluid
fluid between cells (intercellular) , usually high in sodium and chloride. large component of extracellular fluid.
Intracellular fluid
fluid inside cells, usually high in potassium and phosphate. accounts for approx 2/3 of body's water.
intravascular fluid
fluid within blood cells.
Hormones Regulate Blood Calcium
include: vitamin D, parathyroid hormone (PTH), and calcitonin. If blood levels of calcium are too high, muscles contract but then can not relax; this is called calcium rigor. Rising blood calcium levels trigger the thyroid gland to secrete calcitonin. Calcitonin inhibits the activation of vitamin D to its hormone form, and therefore, intestinal absorption decreases, kidney reabsorption decreases, and osteoclasts are not stimulated. If blood calcium levels drop, three organs are affected: 1. Small intestine: Vitamin D induces intestinal Ca-binding proteins causing increase in absorption of dietary Ca into the body. For adults on a typical American diet, only about 30% of dietary Ca is absorbed so there is plenty of spare Ca in the gut to be absorbed when needed. 2. Kidney: The parathyroid gland is signaled to secrete PTH. PTH travels to the kidney and stimulates the activation of vitamin D (i.e. hydroxylation reactions). PTH and active vitamin D together increases re-absorption of Ca, drawing Ca back into the body instead of being excreted in urine. 3. Bone: As a last resort, if absorption and re-absorption of calcium is not enough, vitamin D and PTH stimulate osteoclasts to break down bone for the release of Ca into blood. (Note that vitamin D actually aids in taking Ca out of bone.)
Iron Deficiency
iron deficiency refers to depleted iron stores in the liver, but not severe enough to cause anemia. Iron deficiency may cause behavioral and motivational changes often mistaken for laziness; symptoms may include fatigue, decreased ability to concentration, and sluggish reactivity. In the U.S., some behavior and cognitive problems in children have been attributed to lower iron status. Researchers hypothesize that iron's role in the synthesis of neurotransmitters is the cause of these symptoms. Thus, a physical exam along with information about dietary adequacy of iron is important in assessing health status of children. At this time, assessing body iron storage is too expensive as a routine clinical check for iron deficiency.
water recommendations
vary depending on body size, activity, environmental temp and humidity. adult water recommendations (US) are approx 1 to 1.5 ml/kcal. if a person expends 2000 kcal, 2-3 liters of fluids is recommended. "caffeinated beverages contribute to daily total water intake similar to that contributed by non-caffeinated beverages" intake must balance loss.