Ch. 9-12; 19
key roles of iodine
component of thyroid hormones; for normal thyroid function
what two mineral interfere with zinc absorption when taken in excess?
copper or iron
what is Warnicke-Korsakoff syndrome and who primarily develops it?
degenerative brain disorder associated with a deficiency of thiamin and most commonly caused by excessive alcohol consumption; This syndrome occurs primarily in *alcoholics* in the United States, because alcohol reduces thiamin absorption and increases the vitamin's excretion. Signs of Wernicke-Korsakoff syndrome include abnormal eye movements, staggering gait, and distorted thought processes. Treatment involves eliminating alcohol and obtaining thiamin injections. Without prompt treatment, people with Wernicke-Korsakoff syndrome can become disabled permanently or die.
key roles of chromium
enhances insulin action; Chromium is also important for carbohydrate, fat, and protein metabolism and storage. For people who are trying to lose weight, chromium supplementation may contribute to a small amount of weight loss; glucose regulation
deficiency of Vit K
excessive bleeding, increased time for blood to clot; No RDA, AI for Vit K are 120 μg/day for men and 90 μg/day for women.
What are the two classes of vitamins? How are they absorbed and stored?
fat-soluble and water-soluble; fat-soluble are found in lipid portions of foods and tend to associate with lipids in the body, digested and absorbed with fats in the GI tract; water-soluble are dissolved in the watery components of food and the body
which vitamins are fat soluble? which are water soluble?
fat-soluble: Vit A,D,E,K; water-soluble: thiamin, riboflavin, niacin, Vit B6, pantothenic acid, folate, biotin, Vit B12 (B Vitamins), Vit C
is fluoride an essential nutrient?
no because it is not required for growth or to sustain life
EPA
oversees the quality of our drinking water by: establishing safe drinking water standards assisting state officials in their efforts to monitor water quality regulating toxic substances and wastes to prevent their entry into foods and the environment
which groups of people have higher iron needs?
pregnant women, periods of rapid growth, heavy menstrual bleeds, young children, vegetarians, athletes who regularly perform long-distance running
what is the primary regulator of fluid intake?
thirst
within what time frame should foods be returned to the refrigerator?
to be safe, cover leftovers and refrigerate or freeze them as soon as people have finished eating, or within 2 hours. If environmental temperatures are above 90°F, refrigerate the leftovers within 1 hour
what amino acid can be converted to niacin?
tryptophan
what characteristics does a food have to have to promote pathogen growth?
warmth, moisture, and a source of nutrients, and some also require oxygen; potentially hazardous foods are warm and moist, contain some protein, and they have a neutral or slightly acidic pH
what is the most common cause of preventable intellectual disability around the world?
worldwide iodine deficiency
toxicity of Vit K
Adult UL =undetermined Unknown; ingesting amounts of vitamin K that exceed the AIs has not been reported to be harmful to humans.
toxicity of Vit A
Adult Upper Limit (UL) =3000 µg/day Nausea and vomiting, headaches, bone pain and fractures, hair loss, liver damage, interference with vitamin K absorption; Excessive consumption of vitamin A can damage the liver, because the organ is the main site for vitamin A storage. Toxicity signs and symptoms include headache, nausea, vomiting, visual disturbances, hair loss, bone pain, and bone fractures.
where should foods be thawed?
Always thaw high-risk foods in the refrigerator, under cold running water, or in a microwave oven.
how much Vit C should smokers add and why?
Cigarette smokers should add an extra 35 mg/day to their RDA, because exposure to tobacco smoke increases radical formation in the lungs.
key roles of selenium
Component of an antioxidant system; thyroid hormone function and immune system; reproduction and DNA synthesis
key roles of iron
Component of hemoglobin and myoglobin that carries oxygen Energy generation Immune system function; nervous system, cell division 1. transferrin receptors increase in response to low iron; 2. transferrin transports iron; 3. transferrin binds to transferrin receptor
key roles of zinc
Component of numerous enzymes; growth and development, wound healing, the sense of taste and smell, DNA synthesis, and proper functioning of the nervous and immune systems.
food sources of chromium
Egg yolks, whole grains, pork, nuts, mushrooms; meat, whole-grain products, yeast, spices, fruits, and vegetables are good sources of chromium
food sources of niacin
Enriched breads and cereals, beef, liver, tuna, salmon, poultry, pork, mushrooms
can Vit C supplements cure a cold?
Evidence collected from several scientific studies indicates that routine vitamin C supplementation (200 mg or more of the vitamin daily) *does not* prevent colds in the general population. *However*, taking such large doses of the vitamin may reduce the duration of cold symptoms by a day or so.54 Additionally, vitamin C may reduce the severity of cold symptoms because the micronutrient acts like an antihistamine when taken in very large doses.55
deficiency of iron
Fatigue upon exertion Small, pale red blood cells Low hemoglobin levels Poor immune system function Growth and developmental retardation in infants (women 18 mg, men 8 mg)
food sources of iodine
Iodized salt, saltwater fish, dairy products; Major sources of iodine include saltwater fish; seafood; seaweed; some plants, especially the leaves of plants grown near oceans; milk; eggs; and iodized salt. A half teaspoon of iodide-fortified salt supplies the adult RDA for iodine. Adding iodide to salt is voluntary in the United States, so not all salt has the trace mineral added to it.
deficiency of potassium
Irregular heartbeat; hypokalemia Muscle cramps (RDA 4700 mg)
what was done in 1998 to prevent a shortage of folate in women of childbearing age? What was the result?
January 1998 guidelines from the FDA requiring the addition of folic acid to enriched flour and cereals. At that time, medical experts estimated that at least half the cases of neural tube defects could be prevented if women consumed sufficient folic acid before conception and in early pregnancy.24,25 For pregnant women, adequate folate status is critical early in pregnancy, because the neural tube begins to form about 21 days after conception.26 This developmental milestone occurs when many women are not even aware they are pregnant. Each year, about 1500 babies are born with spina bifida in the United States.27,28 However, the prevalence of neural tube defects has declined by about 30% since enrichment of foods with folic acid began in 1998.
protecting food supply
Local health departments are responsible for inspecting: restaurants grocery stores dairy farms local food processing companies
deficiency of Vit E
Loss of muscular coordination, hemolysis of red blood cells resulting in anemia, nerve damage, blindness, reduced immune system function; RDA for Vit E is 15 mg/day of alpha-tocopherol
why is the UL of magnesium lower than the RDA for men?
Magnesium toxicity, hypermagnesemia, rarely occurs from eating too much magnesium-rich food.42 The toxicity is more likely to occur from ingesting excessive magnesium from laxatives, antacids, or dietary supplements that contain the mineral. Thus, the UL for the micronutrient (350 mg/day) is for magnesium-containing medications and not food sources. A person who ingests too much magnesium often develops diarrhea as a result.
key roles of potassium
Maintenance of proper fluid balance Transmission of nerve impulses Maintenance of acid-base balance
key roles of sodium
Maintenance of proper fluid balance Transmission of nerve impulses Muscle contraction Transport of certain substances into cells
according to the dietary guidelines which vitamins are a nutrient of public concern?
Many Americans, however, consume less than recommended amounts of vitamins A, D, E, and K
food sources of iron
Meat and other animal foods, except milk; whole-grain and enriched breads and cereals; fortified cereals
food sources of selenium
Meat, eggs, fish, seafood, whole grains; seafood and organ meats such as liver and kidneys, poultry, nuts
food sources of B6
Meat, fish, and poultry; potatoes, bananas, spinach, sweet red peppers, broccoli
deficiency of folate
Megaloblastic anemia, diarrhea, neural tube defects in embryos; RDA 400 μg, increase to 600 μg (DFE)/day during pregnancy and 500 μg (DFE)/day in breastfeeding
deficency of fluoride
Men: 4 mg Women: 3 mg; No true deficiency, but increased risk of tooth decay
food sources of calcium
Milk and milk products, canned fish, tofu made with calcium sulfate, leafy vegetables, calcium-fortified foods such as orange juice; broccoli and leafy greens, especially kale, collard, turnip, bok choy, and mustard greens. Nevertheless, the calcium in plant foods is generally not as bioavailable as the calcium in milk and milk products
food sources of riboflavin
Milk, yogurt, and other milk products; enriched breads and cereals; liver; Mushrooms, broccoli, asparagus, and spinach and other green leafy vegetables also contain substantial amounts of the vitamin
what is the danger zone for microbial growth?
Most microbes grow well when the temperature of a potentially hazardous food is between 40°F and 140°F—the "danger zone"
deficiency of sodium
Muscle cramps (RDA 1500 mg (19-50 yrs old); hyponatremia
deficiency of selenium
Muscle pain and weakness Form of heart disease (RDA 55 μg)
deficiency of magnesium
Muscle weakness and pain Poor heart function; Men: 400-420 mg Women: 310-320 mg
deficiency of Vit A
Night blindness, xerophthalmia, poor growth, dry skin, reduced immune system functioning; RDA for vitamin A is 700 to 900 μg RAE
toxicity of potassium
No UL has been determined; hyperkalemia Slowing of heart rate that can result in death
toxicity of Vit B12
None (UL not determined)
toxicity of riboflavin
None (UL not determined)
toxicity of thiamin
None (upper limit [UL] not determined)
deficiency of phosphorus
None reported (RDA 700 mg)
key roles of Vit A
Normal vision and reproduction, cellular growth, and immune system function, cell production, formation of epithelial cells
key roles of phosphorus
Structural component of bones and teeth Maintenance of acid-base balance Component of DNA, phospholipids, and other organic compounds; Synthesize adenosine triphosphate (ATP) and creatine phosphate, substances that are essential for energy production; Synthesize phospholipids, DNA, and RNA; Regulate acid-base balance; and Activate many enzymes and hormones necessary for energy metabolism. 700 mg
food sources of sodium
Table salt; luncheon meats; processed foods; pretzels, chips, and other snack foods; condiments; sauces
food sources of Vit E
Vegetable oils and products made from these oils, certain fruits and vegetables, nuts and seeds, fortified cereals; sunflower seeds, almonds, and plant oils, especially sunflower, safflower, canola, and olive oils. Products made from vitamin E-rich plant oils, such as margarine and salad dressings, also supply the micronutrient. Other important dietary sources of the vitamin include fish, whole grains, nuts, seeds, and certain vegetables
what non-food source does the body use to synthesize Vit D?
Vitamin D is not widespread in food; therefore, the body depends on sunlight exposure to synthesize the vitamin.
food sources of Vit D
Vitamin D-fortified milk, fortified cereals, fish oils, fatty fish
why do people that use blood thinners (warfarin) need to monitor vitamin k intake?
Vitamin K can interfere with warfarin's "blood-thinning" activity, so people who take this medication should not consume vitamin K supplements.56,57 Additionally, these patients should try to maintain consistent dietary intakes of the vitamin each day.
what are the minerals that the Dietary Guidelines mark as nutrients of public concern?
calcium, potassium (phosphorus, sodium, magnesium, chloride, sulfur)
toxicity of Vit C
Adult UL = 2000 mg/day Diarrhea and GI tract discomfort; prooxidant which promotes production of free radicals
toxicity of niacin
Adult UL = 35 mg/day Flushing of facial skin, itchy skin, nausea and vomiting, liver damage
toxicity of Vit D
Adult UL =100 µg/day Poor growth, calcium deposits in soft tissues
Toxicity of Vit E
Adult UL =1000 mg/day Excessive bleeding as a result of interfering with vitamin K metabolism
toxicity of folate
Adult UL =1000 µg/day May stimulate cancer cell growth
key roles of Vit C
(Ascorbic acid) Connective tissue synthesis and maintenance, antioxidant, synthesis of neurotransmitters and certain hormones, immune system functioning; form and maintain collage; connections between amino acids, strengthen connective tissue; *NOT* a coenzyme
what is pasteurization? what is Aseptic processing?
*Pasteurization* is a special heating process used by many commercial food producers to kill pathogens. The nutrient composition of pasteurized foods may be slightly lower than that of unpasteurized foods, but the benefits of pasteurization far outweigh the loss of nutrients. pasteurization process that *kills the pathogens in foods and beverages as well as many microbes responsible for spoilage* in diary products and juices, and the nutrient composition may be slightly lower but the benefit often outweighs the risk; Kills or deactivates pathogens; destroys enzymes that result in food spoilage; *Aseptic processing* involves *sterilizing a food and its package separately*, before the food enters the package. The sterilization process destroys all microorganisms and viruses, as compared to pasteurization, which is a less extensive heating process that kills most pathogens. This process makes products such as milk and juice shelf stable until the package is open. After undergoing aseptic packaging, boxes of sterile foods and beverages, such as milk or juices (Fig. 19.9), can remain free of microbial growth for several years while sitting on supermarket or pantry shelves. However, once the containers of these products are opened, the foods or beverages have the same shelf life as their counterparts that have not undergone aseptic processing
what does the food additives amendment state?
*legislation that requires evidence that a new food additive is safe before it can be marketed for use*; According to this amendment, an ingredient that had been in use prior to 1958 was Generally Recognized as Safe (GRAS) when qualified experts generally agreed that the substance was safe for its intended use. The Food Additives Amendment excluded GRAS substances from being defined as food additives.25 Thus, modern food manufacturers can use substances on the GRAS list as ingredients without testing them for safety or getting prior approval from the FDA. A food additive is any substance that becomes incorporated into food during production, packaging, transport, or storage. The Food Additives Amendment is U.S. legislation that requires evidence that a new food additive is safe before it can be marketed to use.
what groups of people are most vulnerable to food poisoning?
*pregnant women, very young children, older adults, and persons who suffer from serious chronic illnesses or weakened immune systems*. Very young children typically have underdeveloped immune systems, increasing their susceptibility, whereas older adults can have decreased immune responses due to the aging process. In addition, older adults may produce less gastric acid, which can reduce their ability to kill any bacteria consumed in foods
what is cross-contamination and how can someone prevent it in?
*transferring of pathogens from a contaminated food or surface to an uncontaminated food or surface* Ex. Using the same cutting board to cut raw meat and raw fruits and vegetables Transporting cooked meat on the same plate used to transport raw meat. Using the same utensils to handle raw meat and raw produce. *To prevent cross contamination be sure to wash: Hands (20 seconds) Surfaces Cutting boards FDA recommends using nonporous material such as plastic, marble, or glass. Wooden cutting boards should be nonabsorbent with no cracks or seams. Utensils and other equipment* Hands Wash hands thoroughly with very warm, soapy water for at least 20 seconds before and after touching food. If clean water for hand washing is not available, use sanitizing hand wipes. If you are preparing more than one type of food, such as cutting up chicken and dicing carrots, wash hands in between. Use a fresh paper towel or clean hand towel to dry hands. Reserve dish towels for drying pots, pans, and cooking utensils that are not washed and dried in a dishwasher. Surfaces Before preparing food, clean food preparation surfaces, including kitchen counters, cutting boards, dishes, knives, and other food preparation equipment, with hot, soapy water. Sanitize food preparation surfaces and equipment that have come in contact with raw meat, fish, poultry, and eggs as soon as possible. Sanitizing is a process that uses heat or chemicals to destroy pathogens. Most pathogens on surfaces can be killed by using a sanitizing solution made by adding a tablespoon of bleach to 1 gallon of cool water.17 However, avoid getting bleach solution on colored fabrics or surfaces that can be damaged by bleach (granite, for example). Cutting boards The FDA recommends using cutting boards with unmarred surfaces made of easy-to-clean, nonporous materials, such as plastic, marble, or glass. If you prefer to use wooden cutting boards, make sure they are made of a nonabsorbent hardwood, such as oak or maple, and have no obvious seams or cracks. Replace cutting boards when they become streaked with cuts, because these grooves can be difficult to clean thoroughly and may harbor bacteria. If possible, have a cutting board reserved for meats, fish, and poultry; another cutting board for fruits and vegetables; and a third board for breads. Utensils and other equipment Do not reuse cooking utensils such as tongs, knives, or spoons that have previously touched raw meat, fish, poultry, or eggs unless they have been sanitized first. Sanitize kitchen sponges and wash kitchen towels frequently.
key roles of Vit D
Absorption of calcium and phosphorus, maintenance of normal blood calcium, calcification of bone, maintenance of immune function
toxicity of B6
Adult UL = 100 mg/day Nerve destruction
what is the UL for sodium? what is the average intake of sodium in the US?
2300 mg/day; Americans on average consumed more than 3450 mg of sodium per day in 2011-2012
how long until leftovers should be thrown out?
4 days
why do women of childbearing age want to be especially aware of folate intake?
A pregnant woman has an increased requirement for folate, because DNA synthesis and cell division take place at a rapid pace during embryonic development.23 During the first few weeks after conception, the neural tube forms in the human embryo (Fig. 10.11a). This tube eventually develops into the brain and spinal cord. Pregnant women who suffer from folate deficiency have high risk of giving birth to infants with neural tube defects (NTDs). The two most common NTDs are spina bifida and anencephaly; In 1992, officials with the U.S. Public Health Service recommended that all women capable of becoming pregnant consume 400 μg of folic acid daily to help prevent neural tube defects.
what is the process of digesting and absorbing B12?
Absorbing the vitamin B-12 that is naturally in food requires a complex series of steps (Fig. 10.12). Natural vitamin B-12 is bound to animal protein that prevents its absorption. When the food enters the stomach, the vitamin is released from the protein, primarily by the actions of hydrochloric acid (HCl) in gastric juice. Synthetic vitamin B-12 in dietary supplements or fortified foods is not bound to food protein, so it does not need stomach acid to release the protein. Thus, synthetic vitamin B-12 is more readily absorbed than the natural form of the micronutrient; In the small intestine, vitamin B-12 binds to intrinsic factor (IF), a compound that is produced by parietal cells of the stomach. Eventually, the vitamin B-12/intrinsic factor complex reaches the ileum of the small intestine, where the vitamin complex is absorbed. Within the absorptive cells, vitamin B-12 is separated from intrinsic factor and attached to transport molecules. The transport molecules enter the bloodstream and travel to the liver via the hepatic portal vein. The liver removes vitamin B-12 from many of the carrier molecules and stores about 50% of the vitamin. A healthy liver has enough vitamin B-12 reserves to last 5 to 10 years.35 Therefore, a healthy person who decides to follow a diet that completely lacks vitamin B-12 is not likely to experience signs and symptoms of the vitamin's deficiency disorder for as long as 10 years. Even though vitamin B-12 is stored in the liver, no UL has been established for the micronutrient, because no adverse effects have been observed with excess intakes; 1. HCL separates B12 from animal protein 2. stomach secretes intrinsic factor 3. B12 binds to IF 4. The IF/B12 complex enters the cells and the complex breaks apart 5. B12 binds to carrier molecule for transport in the blood
food sources of Vit B12
Animal foods, fortified cereals, fortified soy milk; Only bacteria, fungi (for example, mushrooms and molds), and algae can synthesize vitamin B-12; people rely almost entirely on animal foods to supply the vitamin naturally. Major sources of vitamin B-12 in the typical American diet are meat, milk and milk products, poultry, fish, shellfish, and eggs. Although liver is not a popular food, it is one of the richest sources of vitamin B-12 because the vitamin is stored in the liver.
in the US, food manufacturers are required to enrich breads and cereals made from milled, refined grains with which B vitamins?
B1 (thiamine) B2 (riboflavin) B3 (niacin), B9 (folate)
why are newborns given Vit K?
Babies are generally born with low vitamin K stores, and a deficiency of the vitamin can occur soon after birth because of the newborn's immature GI tract.61 Vitamin K-deficient infants are at risk of serious bleeding because their bodies are unable to make certain blood-clotting factors. To prevent vitamin K deficiency from developing during infancy, newborns generally receive a single injection of vitamin K immediately after birth.
what non-food source provides Vit K?
Bacteria that normally live in the large intestine also synthesize menaquinones that can be absorbed by the body. Bacterial *menaquinone* contributes about 10% to the body's vitamin K supply. The biological activity of phylloquinone is greater than that of menaquinone. A synthetic form of vitamin K, menadione, can be converted into menaquinone in the body
deficiency of thiamin
Beriberi and Wernicke-Korsakoff syndrome: Weakness, abnormal nervous system functioning; RDA 1.1 mg for women 1.2 mg for men
deficiency of chromium
Blood glucose level remains elevated after meals; Men: 30-35 μg Women: 20-25 μg
by what age is most bone mass developed and when does bone mass start to decline?
By *20* years of age, healthy young men and women have acquired 85 to 90% of their adult bone mass (peak bone mass).21 Loss of bone mass begins in *mid-adulthood* as levels of testosterone and estrogen ("sex hormones"), which are needed for normal bone development and maintenance, begin to decline. In women, however, the rate of bone loss increases significantly after *menopause*; that is, after menstrual cycles have ceased.
do calcium rich diets have beneficial effects on the heart? what about calcium supplements?
Calcium-rich diets have beneficial effects on heart disease risk factors, including hypertension, insulin resistance, chronic inflammation, and abnormal blood lipid levels.24,25 Although dietary calcium may protect against heart disease, calcium supplements have actually been associated with an increased risk of cardiovascular disease (CVD). Dietary sources of calcium may also be associated with successful weight loss and improved body composition. A high-calcium diet may increase fat breakdown, accelerating fat loss.27 However, more research is needed to clarify whether calcium intake can reduce the risk of heart disease and aid weight loss efforts.
how can one avoid acrylamide?
Consumers can avoid producing acrylamide during cooking by boiling, steaming, and microwaving potatoes and grains. Sources of acrylamide include overly browned potato- and grain-based foods, so it is wise to avoid eating burnt bread or French fries. Acrylamide is a naturally occurring compound in foods. Formed when foods containing sugars and asparagine are heated to high temperatures Avoid producing acrylamide by boiling, steaming, and microwaving potatoes and grains Avoid eating burnt bread or French fries
what may happen to iron status when children drink too much milk? why?
Consuming too much milk may play a role in the development of iron deficiency in children. Milk is a poor source of iron, and the calcium that is in milk interferes with iron absorption when the beverage is consumed with foods that contain the trace mineral.1 To reduce the risk of iron deficiency, children should be encouraged to eat more iron-rich foods, such as lean meats and iron-fortified cereals.
what temperature should foods be cooked to? (see table 19.4)
Cook the food until it reaches 165°F; Beef, pork, and lamb steaks or roasts 145°F Ground beef, pork, or lamb 160°F Poultry (whole or ground) 165°F Eggs 160°F Seafood 145°F Casseroles, stuffing, or other mixed dishes 165°F
food sources of phosphorus
Dairy products, processed foods, soft drinks, fish, baked goods, meat; seeds and beans
food sources of folate
Dark green, leafy vegetables; liver; legumes; asparagus; broccoli; orange juice; enriched breads and cereals (folic acid)
deficiency of B6
Dermatitis, anemia, depression, confusion, and neurological disorders such as convulsions; RDA 1.3—1.7 mg
How can someone lower the risk of age-related macular degeneration?
Diets supplying high amounts of carotenoids (beta-carotene, lutein, and zeaxanthin) may lower the risk of AMD
what groups of people are at increased risk of Vit D deficiency?
Earth's atmosphere blocks UV radiation. In North America, the 37th parallel extends from about southern Virginia through southern Missouri to San Francisco, California (Fig. 9.17). For those living north of the 37th parallel, the angle of the winter sun is such that the sun's rays must pass through more of the atmosphere than at other times of the year (Fig. 9.18). As a result, skin cannot make sufficient amounts of provitamin D during the winter and a person may not have adequate vitamin D stored in his or her body to last until spring; If you live north of the 37th parallel, the angle of the winter sun is such that the sun's rays must pass through more of the atmosphere than at other times of the year. As a result, skin tends to form less prohormone vitamin D in the winter. Ex. African American women
how is sodium related to hypertension? what blood pressure values are considered hypertension?
Eating salt raises the amount of sodium in your bloodstream and wrecks the delicate balance, reducing the ability of your kidneys to remove the water. The result is a higher blood pressure due to the extra fluid and extra strain on the delicate blood vessels leading to the kidneys. Hypertension, a condition characterized by persistently elevated blood pressure, is a serious public health problem in the United States. Compared to people with normal blood pressure, hypertensive individuals have greater risk of CVD, especially heart disease and stroke, as well as kidney failure and damage to other organs.33 Approximately 30% of adult Americans have hypertension.34 Children can also develop hypertension; among U.S. adolescents, 22% of boys and 10% of girls have high blood pressure; Hypertension ≥ 140 systolic or ≥ 90 diastolic
how can someone prevent/slow the progression of bone loss?
Efforts to reduce the risk of osteoporosis should begin early to maximize peak bone mass. Proper diet and regular exercise are especially important from early childhood through late adolescence, because the body actively builds bone during these life stages. Exposing skin to sunlight can stimulate the body's ability to form vitamin D, but some people will need to take calcium and vitamin D supplements. Exercise training, especially performing weight-bearing activities, increases bone mass, because contracting muscles keep tension on bones, which stimulates bone-building activity
food sources of fluoride
Fluoridated water, tea, seaweed; beer, coffee, shrimp
Food Preservation
Food irradiation preserves food by using a high amount of ionizing radiation to kill pathogens. The food items are not radioactive. According to the WHO, FDA, and CDC, irradiated foods are safe to eat.
what are guidelines to follow when selecting food?
Food selection guidelines emphasize selecting unexpired foods, purchasing fresh produce, and keeping cold or frozen foods at the proper temperature during transport home. To reduce the risk of food-borne illness: Packaged and fresh perishable foods Check "best by" dates on packaged perishable foods. Choose meats and other animal products with the latest dates. Do not buy food in damaged containers; for example, avoid cans that leak, bulge, or are severely dented, or jars that are cracked or have loose or bulging lids. Dairy and eggs Open egg cartons and examine eggs; do not buy cartons that have cracked eggs. Purchase only pasteurized milk and cheese, as well as fruit and vegetable juices (check the label). Store whole eggs in their cartons, even if the refrigerator has a place for storing eggs. Egg cartons are designed to keep eggs fresh longer than a refrigerator's egg compartment. Meats, fish, and frozen foods When shopping in a supermarket, select frozen and cold foods last, especially potentially hazardous foods such as meats, poultry, dairy, or fish. Pack meat, fish, and poultry in separate plastic bags, so their drippings do not contaminate each other and other groceries. After shopping for food, take groceries home immediately. Refrigerate or freeze meat, fish, egg, and dairy products promptly. *selecting unexpired foods purchasing fresh produce keeping cold or frozen foods at the proper temperature during transport home do not use foods from containers that have damaged safety lids do not taste or use food that spurts liquid or has a bad odor carefully wash foods under running water avoid eating moldy foods when in doubt, throw the food away*
what are the signs and symptoms of food-borne illness?
Food-borne illness is an infection caused by microscopic disease-causing agents in food. Each year, an estimated 48 million Americans become sick from food-borne illnesses. 128,000 require hospitalization Over 3,000 die; involve the digestive tract and include nausea, vomiting, diarrhea, and intestinal cramps; The incubation period is the length of time in which bacteria can grow and multiply in food or the digestive tract before they cause illness. Ranges from 1 hour to several days *bacteria and viruses are biggest cause*
what foods are most associated with Listeriosis? What group of people should be especially careful about these foods?
Foods typically associated with listeriosis include *raw milk; soft cheeses made from raw milk; raw, undercooked, and smoked seafood; and ready-to-eat processed meats, such as hot dogs, luncheon meats, or deli meats*. A pregnant woman is 13 to 14 times more likely to contract listeriosis than is a nonpregnant woman; This illness can be passed from mother to unborn offspring, resulting in: miscarriages premature delivery serious health problems for the newborn
food sources of potassium
Fruits, vegetables, milk, meat, legumes, whole grains, dried beans, fruit juice
Food Additives
Generally Recognized as Safe (GRAS) are ingredients that have been used for so long and are thought to be safe. The Delaney Clause is a component of the 1958 Food Additives Amendment that prevents manufacturers from adding carcinogenic compounds to foods.
deficiency of iodine
Goiter Cretinism (intellectual impairment and poor growth in infants of women who were iodine deficient during pregnancy) (RDA 150 μg)
what is goiter? what populations generally develop goiter?
Goiter is an enlargement of the thyroid gland that is not the result of cancer (Fig. 12.7). Goiters often occur among populations living in areas that lack the mineral iodine in locally produced foods; places where soils are iodine deficient and commonly eaten foods are not fortified with the trace mineral. Approximately 35% of the world's population is at risk for iodine deficiency, including people living in regions of Latin America, India, Southeast Asia, and Africa
Food sources of Vit K
Green leafy vegetables, canola and soybean oils, and products made from these oils; kale, turnip greens, salad greens, cabbage, and spinach; broccoli; and green beans. Other reliable sources of the vitamin are soybean and canola oils, and products made from these oils, such as margarine and salad dressing
what are dietary practices to reduce cancer risk?
High intakes of fruits and vegetables reduce the risk of cancer, especially lung, oral, esophageal, stomach, and colon cancers.62 Fruits and vegetables are rich sources of vitamin C, as well as carotenoids and other phytochemicals that may have antioxidant activity in the body. Antioxidants protect DNA from free-radical damage, preventing potentially cancer-causing mutations from occurring. Although research is ongoing, results of scientific studies generally have not shown that taking dietary supplements containing antioxidants reduces the risk of cancer.66,67 Some medical experts are concerned that taking antioxidant supplements may increase the risk of lung and prostate cancers, especially among smokers and men with family histories of prostate cancer; Avoiding exposure to tobacco smoke; Achieving and maintaining a healthy weight; Adopting a physically active lifestyle; and Eating a healthy diet that limits intake of red and processed meats and emphasizes plant foods, including fruits, vegetables, and whole grains.
why might a doctor prescribe megadoses of niacin?
However, physicians may prescribe megadoses of niacin supplements containing nicotinic acid to reduce elevated LDL cholesterol levels and increase HDL cholesterol levels in blood (Fig. 10.7).9 For patients who cannot tolerate statins (see Chapter 6), taking megadoses of niacin can reduce their risk of stroke and heart attack
does science support the use of B6 supplements to relive premenstrual syndrome (PMS)?
However, there is not enough scientific evidence to support the use of dietary supplements containing vitamin B-6 for relieving PMS and morning sickness.
what is Keshan disease, Kashin-Beck disease, and selenosis?
In parts of China where the soil lacks selenium and the population consumes only locally produced foods, diets are typically inadequate in selenium. Keshan disease, a cardiomyopathy (disease of the heart muscle), was common in selenium-deficient regions of China before food in the area was fortified with selenium. In areas of China, Tibet, Siberia, and North Korea, a form of osteoarthritis called Kashin-Beck disease develops as a result of selenium deficiency.23 Kashin-Beck disease is a degeneration of the cartilage between joints, which leads to deformity and dwarfism. The UL for selenium is 400 μg/day. In the United States, selenium toxicity (selenosis) (sell'-in-o-sis) is rare.22 Chronic selenosis, however, can occur from drinking well water that contains naturally high levels of selenium. Selenium toxicity can develop by taking megadoses of dietary supplements. In humans, signs and symptoms of chronic selenosis include brittle fingernails, loss of hair and nails, garlicky body odor, nausea, vomiting, and fatigue.
how does leavened bread help with the absorption of zinc?
In places where people use yeast to leaven (raise) bread dough, severe zinc deficiency is less likely to occur. Yeast reduces the binding effects of phytic acid and fiber, making zinc more bioavailable.
deficiency of calcium
Increased risk of osteoporosis May increase risk of hypertension (1000-1200 mg)
key roles of fluoride
Increases resistance of tooth enamel to cavity formation Stimulates bone formation
deficiency of riboflavin
Inflammation of the mouth and tongue, eye disorders, dermatitis, Glossitis and cheilosis can be symptoms of several medical conditions, including ariboflavinosis. In cases of ariboflavinosis, the tongue is reddish-purple in color.; RDA 1.1 mg women 1.3 mg for men
what do the three organ systems in the body do to maintain calcium balance? (See figure 11.11)
Parathyroid hormone (PTH) and calcitonin work together to maintain blood calcium homeostasis. When blood calcium levels fall, the parathyroid gland secretes PTH. PTH stimulates vitamin D activity and increases osteoclast activity, calcium retention in the *kidneys*, and calcium absorption in the small intestine. When blood calcium levels rise, calcitonin is secreted from the *thyroid gland*. Calcitonin inhibits vitamin D, increases osteoblast activity, and decreases calcium retention in the kidneys and calcium absorption in the *small intestine*.
key roles of riboflavin
Part of FMN and FAD, coenzymes needed for carbohydrate, amino acid, and lipid metabolism; enzymatic reactions, including those that are critical to energy, fatty acid, and folate metabolism. The liver, kidneys, and heart store small amounts of riboflavin; any excess intake is excreted rapidly in the urine.
key roles of niacin
Part of NAD and NADP, coenzymes needed for energy metabolism
key roles of B6
Part of PLP, coenzyme needed for amino acid metabolism, involved in neurotransmitter synthesis and hemoglobin synthesis; A major role of PLP is to facilitate enzymatic reactions involved in amino acid metabolism, including the conversion of the amino acid tryptophan to niacin and the transamination reactions that form nonessential amino acids; PLP also helps convert a toxic amino acid, homocysteine, to cysteine, a nonessential amino acid. If the body lacks vitamin B-6, homocysteine can accumulate in blood and may contribute to cardiovascular disease
key roles of folate
Part of THFA, coenzyme needed for DNA synthesis and conversion of cysteine to methionine, preventing homocysteine accumulation
key roles of thiamin
Part of TPP, remove CO2 from a larger compound, coenzyme needed for carbohydrate metabolism and the metabolism of certain amino acids; may help produce neurotransmitters 1.1—1.2 mg
key roles of Vit B12
Part of coenzymes needed for various cellular processes, including folate metabolism; maintenance of myelin sheaths
deficiency of niacin
Pellagra Diarrhea Dermatitis Dementia Death (RDA 14-16 mg)
food sources of Vit C
Peppers, citrus fruits, papayas, broccoli, cabbage, berries; Potatoes and vitamin C-fortified fruit drinks and ready-to-eat cereals also supply vitamin C. Most animal foods are not sources of the micronutrient.
deficiency of Vit B12
Pernicious anemia: megaloblastic anemia and nerve damage resulting in paralysis and death;RDA 2.4 μg; Vegans, for example, need to be concerned about their intake of vitamin B-12, because plant foods are not sources of the micronutrient (see the "Vegetarianism" section of Chapter 7). Vitamin B-12 deficiency is characterized by nerve damage and megaloblastic RBCs. Other signs and symptoms of the deficiency include muscle weakness, smooth and shiny tongue, confusion, difficulty walking and maintaining balance, and numbness and tingling sensations, particularly in the hands and feet; in pregnant women it can cause neural tube deficiency in the embryo
food sources of thiamin
Pork, wheat germ, enriched breads and cereals, brewer's yeast; Whole-grain and enriched breads and cereals, pork, legumes, and orange juice are good food sources of thiamin. Brewer's yeast is a rich source of thiamin, but most Americans do not eat the product
food sources of Vit A
Preformed: liver, milk, fortified cereals Provitamin: yellow- orange and dark green fruits and vegetables; Animal foods such as liver, butter, fish, fish oils, and eggs are good sources of preformed vitamin A, including retinyl esters. Vitamin A-fortified milk, yogurt, margarine, and cereals are important sources of the nutrient for Americans. Carrots, spinach and other leafy greens, pumpkin, sweet potatoes, broccoli, mangoes, and cantaloupe are rich sources of beta-carotene, a carotenoid that the body can convert to vitamin A. (*retinol* in the body)
key roles of Vit K
Production of active blood-clotting factors; Blood contains inactive clotting factors and cell fragments called platelets that are necessary for blood clotting to occur. When a blood vessel is cut, blood in the injured area undergoes a complex series of steps to form a clot that stops the bleeding (Fig. 9.21). A clot is comprised of strands of the protein fibrin that traps blood cells, forming a mesh. The liver synthesizes several blood-clotting factors, and the organ needs vitamin K to produce four of them, including prothrombin, properly. In addition to vitamin K's role in blood clotting, it is also a cofactor for an enzyme that is essential for bone-building cells to produce osteocalcin, a protein needed for normal bone mineralization.
key roles of calcium
Structural component of bones and teeth Blood clotting Transmission of nerve impulses Muscle contraction Regulation of metabolism 1000-1200 mg; body needs calcium to form bones and teeth, the mineral is also involved in muscle contraction, blood clot formation, nerve impulse transmission, and cell metabolism. Additionally, calcium may play important roles in maintaining a healthy blood pressure and immune system.
what are the effects of dehydration?
Rapid weight loss Dry or sticky mouth Low or no urine output Dark urine No tears Sunken eyes Vomiting and/or diarrhea Rapid weight loss is one of the primary and initial signs of dehydration. Every 16 ounces (about 0.5 L) of water that the body loses represents a pound of body weight. When an individual loses 1 to 2% of his or her usual body weight in fluids, the person feels fatigued and thirsty. For example, if a woman weighs 150 pounds and her weight drops 3 pounds after exercising in hot conditions, she has lost 2% of her body weight, primarily as water weight; As the loss of body water approaches 4% of body weight, muscles lose considerable amounts of strength and endurance. By the time body weight is reduced by 7 to 10% as a result of body fluid losses, severe weakness results. At a 20% reduction of body weight, coma and death are likely.
why would someone want to buy milk in a cardboard or opaque plastic container?
Riboflavin's chemical structure is fairly stable, but exposure to light causes the vitamin to break down rapidly. Therefore, riboflavin-rich foods, such as milk and milk products, should not be packaged or stored in clear glass containers.
deficiency of Vit D
Rickets in children, osteomalacia in adults: soft bones, depressed growth, and reduced immune system functioning; RDA for Vit D is 15 μg/day (600 IU/day)
deficiency of Vit C
Scurvy: poor wound healing, pinpoint hemorrhages, bleeding gums, bruises, depression;RDA 75 mg for women 90 mg for men (nonsmokers)
food sources of zinc
Seafood, meat, whole grains
deficiency of zinc
Skin rash Diarrhea Depressed sense of taste and smell Hair loss Poor growth and physical development (women 8 mg; men 11 mg)
what must a person do if they do not produce intrinsic factor?
Some people have an autoimmune disorder that causes the stomach to stop making intrinsic factor. Although a person affected with this disorder consumes adequate amounts of vitamin B-12, the lack of intrinsic factor prevents most of the micronutrient from being absorbed.37 Eventually, this person develops pernicious ("deadly") anemia (a form of vitamin B-12 deficiency).38 As its name implies, pernicious anemia can lead to death. *Treatment involves bypassing the need for intrinsic factor and intestinal absorption, by providing monthly vitamin B-12 injections or a nasal gel that contains the vitamin.* For many individuals who have pernicious anemia, taking large doses of vitamin B-12 floods the intestinal tract with the vitamin and enables a small amount to be absorbed without the need for intrinsic factor
to what temperature should the refrigerator and freezer be set?
Storage Period in Refrigerator (40°F) Storage Period in Freezer (0°F)
key roles of magnesium
Strengthens bone Cofactor for certain enzymes Heart and nerve functioning; Magnesium plays an essential role in many important metabolic and physiological activities, including contraction and relaxation of muscles, enzyme function, energy production, and DNA and protein synthesis.42 Magnesium participates in more than 300 chemical reactions in the body.42 This essential mineral also helps regulate normal muscle and nerve function, as well as blood pressure and blood glucose levels. Additionally, the body needs magnesium to maintain strong bones and a healthy immune system. Magnesium may help prevent and treat diabetes, hypertension, metabolic syndrome, CVD, and asthma.43-45 In addition, magnesium may be useful in the treatment and management of migraine headaches and reduce risk of death from CVD
toxicity of iron
UL = 45 mg/day Intestinal upset Organ damage Death
toxicity of chromium
Unknown but currently under scientific investigation May interact with certain medications
what agencies monitor our food and water supply?
The *Food and Drug Administration (FDA) of the U.S. Department of Health and Human Services and the U.S. Department of Agriculture (USDA) are the key federal agencies* that protect consumers by regulating the country's food industry. Other team members include the *Environmental Protection Agency (EPA) oversees water quality*, the Centers for Disease Control and Prevention (CDC), the Federal Trade Commission (FTC), and state and local governments. (*federal, state, and local agencies*)
what is the DASH diet?
The Dietary Approaches to Stop Hypertension (DASH) diet is low in sodium, total fat, saturated fat, and cholesterol, and high in fruits, vegetables, and low-fat dairy products. Research indicates that people can lower their blood pressure and reduce their risk of CVD by following the DASH diet, losing excess body fat, and increasing their physical activity level.
what foods help enhance iron absorption? which foods reduce iron absorption?
The intestinal tract absorbs the ferrous (Fe2+) form of iron more efficiently than the ferric (Fe3+) form (Fig. 12.3). Under acidic conditions, ferric iron can be converted to ferrous iron. Thus, medications that decrease stomach acidity, such as antacids, may *reduce iron absorption*.1 Calcium and iron compete for absorption in the small intestine, so a meal with high calcium content can inhibit iron absorption. Therefore, people should consume a variety of food sources of iron throughout the day. Some plant foods, such as spinach, contain nonheme iron, but oxalic acid in spinach binds to the mineral, *reducing its absorption*. Other naturally occurring compounds that reduce iron absorption include polyphenols, phytic acid (or phytates), and soy protein. Polyphenols are present in tea, coffee, wine, and some fruits and vegetables. Phytates are in several foods, including whole grains, rice, and legumes. Absorption of iron from phytate-containing legumes, such as soybeans, black beans, lentils, and split peas, may be as little as 2%.1 Soy protein, including the kind used to make tofu, also reduces iron absorption. Certain dietary factors can *enhance iron absorption*, especially of nonheme iron. Foods that are high in vitamin C increase intestinal absorption of the trace mineral. Adding a source of vitamin C to meals can increase the absorption of nonheme iron by 20%.5 People can also increase their absorption of nonheme iron by combining a small amount of heme iron (from meat) with foods that contain nonheme iron. In addition to heme iron, meat, fish, and poultry contain a factor (sometimes called "MFP factor") that enhances the intestinal tract's ability to absorb nonheme iron. *Enhance*: Vit C, Heme Iron, Leavening of bread, fermentation, soaking beans or grains; *Inhibit*: High intake of calcium with iron-containing food, medications that reduce stomach acidity, oxalic acid from foods such as spinach, phytic acid from foods such as whole grains, soy protein such as tofu, polyphenols from foods and beverages, such as tea
Pathogens in food
The microbes that cause food-borne illness can be found anywhere. Air, water, soil, sewage, various surfaces Human skin, nasal passages, large intestine have vast colonies of microbes Pathogens spread by improper personal hygiene, poor food handling practices, and improper heating of food.
why is taking excess amount of fat soluble vitamins more likely to lead to toxicity than taking excess water soluble vitamins?
The reason is that the body generally has more difficulty eliminating excess fat-soluble vitamins because these nutrients do not dissolve in watery substances such as urine. As a result, the body stores extra fat-soluble vitamins, primarily in the liver and in adipose tissue. Over time, these vitamins can accumulate and cause toxicity. In contrast, the body stores only limited amounts of most water-soluble vitamins; vitamin B-12 is an exception. Furthermore, kidneys can filter excesses of water-soluble vitamins from the bloodstream and eliminate them in urine. Thus, water-soluble vitamins are generally not as likely to be toxic as fat-soluble vitamins.
what are simple ways to determine hydration status?
The simplest way to determine if an individual is consuming enough water is to observe the volume of his or her urine. When fluid intake is adequate, the kidneys produce enough urine to maintain fluid balance. If fluid consumption is more than needed, the kidneys eliminate the excess, and the body produces plenty of urine. If fluid intake is limited or the body loses high amounts of fluid, such as through heavy perspiration, the kidneys produce only small amounts of urine. In addition to urine volume, the color of urine may be a useful indicator of hydration status. Straw-colored (light yellow) urine can indicate adequate hydration, whereas dark-colored urine may be a sign of dehydration. However, the color of urine is not always a reliable guide for judging a person's hydration status.8 It is important to recognize that having a urinary tract infection or ingesting certain medications, foods, and dietary supplements, especially those containing the B vitamin riboflavin, can alter urine's color.
what is the process of maintaining normal blood calcium levels?
The thyroid and parathyroid glands secrete certain hormones that help regulate blood calcium levels (Fig. 11.10). In response to falling blood calcium levels, the parathyroid glands secrete parathyroid hormone (PTH), which signals special bone cells called osteoclasts to tear down bone tissue. This process releases calcium from bones so the mineral can enter the bloodstream. PTH also works with vitamin D to increase intestinal calcium absorption and reduce calcium excretion in urine (Fig. 11.11); When the level of calcium in blood is too high, the thyroid gland secretes the hormone calcitonin (cal'-sih-toe-nin). As shown in Figure 11.11, calcitonin signals another type of bone cell (osteoblasts) to remove excess calcium from blood and build bone tissue. Bone formation involves the incorporation of a crystalline structure that contains calcium and phosphorus, called hydroxyapatite, on the framework of bone tissue. As this process of bone mineralization continues, bone tissue gains strength and rigidity.
what is the result of water intoxication and how might it happen?
There is no Upper Limit (UL) for water.4 Water intoxication, however, can occur when an excessive amount of water is consumed in a short time period or the kidneys have difficulty filtering water from blood. The excess water dilutes the sodium concentration of blood, disrupting water balance and resulting in hyponatremia (low blood sodium). As a result of the imbalance, too much water moves into cells, including brain cells. Signs and symptoms of water intoxication may include dizziness, headache, confusion, inability to coordinate muscular movements, bizarre behavior, and seizures.15 If the condition is not detected early and treated effectively, coma and death can result. Healthy people rarely drink enough water to become intoxicated. However, water intoxication can develop in people with disorders that interfere with the kidney's ability to excrete water normally. Marathon runners who consume large amounts of plain water in an effort to keep hydrated during competition may be at risk of water intoxication
Food Safety Modernization Act (FSMA)
This act improves the safety of the nation's food supply by strengthening authority of federal regulating agencies and shifting focus from reaction to prevention. Mandatory inspection of all imported foods Better regulation on food handling by manufactures
toxicity of fluoride
UL = 10 mg/day Stomach upset Staining of teeth during development Bone deterioration; fluorosis
toxicity of iodine
UL = 1100 μg/day Reduced thyroid gland function
toxicity of calcium
UL = 2.0 to 2.5 g/day (2000-2500 mg/day) Intakes > 2.5 g/day may cause kidney stones and interfere with absorption of other minerals; hypercalcemia.
toxicity of sodium
UL = 2300 mg/day Contributes to hypertension in susceptible individuals Increases urinary calcium losses; hyperphosphatemia
toxicity of magnesium
UL = 350 mg/day medication-related Diarrhea
toxicity of phosphorus
UL = 4 g/day Poor bone mineralization
toxicity of zinc
UL = 40 mg/day Intestinal upset Depressed immune system function Supplement use can reduce copper absorption.
toxicity of selenium
UL = 400 μg/day Nausea Vomiting Hair loss Weakness Liver damage
what roles do water play in the body?
Water is a major solvent; many substances, including glucose, dissolve in water. Water often participates directly in chemical reactions, such as those involved in digesting food; Is a solvent Is a major component of blood, saliva, sweat, tears, mucus, and joint fluid Removes wastes Helps transport substances Lubricates tissues Regulates body temperature Helps digest foods Participates in many chemical reactions Helps maintain proper blood pH; Water helps transport water-soluble substances within and outside cells.
food sources of magnesium
Wheat bran, green vegetables, nuts, chocolate, legumes; Magnesium is a critical component in chlorophyll, the green pigment in plants. Therefore, plant foods such as spinach, green leafy vegetables, whole grains, beans, nuts, seeds, and chocolate are the richest sources of magnesium. Animal products such as milk and meats also supply some magnesium
what are the risk factors for hypertension?
advanced age, African-American ancestry, obesity, physical inactivity, smoking cigarettes, and excessive use of alcohol, and high sodium intake are among the major risk factors for the condition; Family history Advanced age African-American ancestry Obesity Physical inactivity Consuming excess sodium Cigarette smoking Consuming excess alcohol Type 2 diabetes
key roles of Vit E
antioxidant; protects polyunsaturated fatty acids in cell membranes from being damaged by free radicals (Fig. 9.20). Such oxidative damage may be associated with the development of atherosclerosis, the process that occurs within arteries and contributes to heart attack and stroke, cancer, and premature cellular aging and death. Other roles for vitamin E include maintaining nervous tissue and immune system function
Vit E exists in one of eight forms: four of the forms are ___?
four of the forms are *tocopherols* (toe-koff'-e-rolls). Only the alpha-tocopherol form of the vitamin is maintained in plasma and used by the body.14 Appendix D includes an illustration of the chemical structure of alpha-tocopherol. Alpha-tocopherol is in many foods and vitamin E supplements; gamma-tocopherol is also in foods, including vegetable oil. However, the biological activity of gamma-tocopherol is significantly lower than that of alpha-tocopherol.
what substances in food and beverages may promote cancer development?
free-radicals
what are the two forms of iron from food and what are the sources? which is better absorbed?
heme iron: found in meat that is absorbed efficiently; nonheme iron: no absorbed as efficiently as heme iron, found in meat, vegetables, grains, supplements, and fortified or enriched foods