nutrition exam 3

Vitamin A,D,E,K

-fat-soluble vitamins

Chloride

-helps maintain body fluid balance DEFICIENCY -excessive chloride loss is the most common cause of chloride deficiency -vomiting expels stomach acid which contains a lot of chloride

Molybdenum

-is essential to both plants and animals -it is efficiently absorbed and is excreted rapidly in urine and bile -deficiency does not occur in people who eat a normal diet -toxicity is unlikely, but a UL is set at 2,000 micrograms per day

B12

-it is essential to the conversion of folate to an activated form -without B12, folate cannot function in the DNA synthesis or blood cells synthesis -it helps maintain the myeline sheath, a protective coating that surrounds nerve fibers SOURCES -animal-derived foods are our only good natural source of vitamin B12, and liver is the richest source DEFICIENCY -its almost due to impaired absorption, especially in older persons -pernicious anemia is a major cause of vitamin B12 deficiency -B12 deficiency causes the anemia, nerve cells can be irreversibly destroyed TOXICITY -high levels of B12 from food or supplements have not been shown to cause harmful side effects in healthy people -large vitamin B12 doses routinely used to treat pernicious anemia have no apparent ill effect

Sodium

-known best as a component of table salt -sodium is critical for regulating both cellular fluid and total body fluid SOURCES -pickled foods, soy beans, salty or smoked meats EXCESS -although some illnesses can drive down blood sodium to dangerously low levels, our bodies usually must deal with an excess of sodium -taking too much sodium or not enough can worsen dehydration

Phytochemicals

-make foods functional -many functional foods get their health-promoting properties from naturally occurring compounds that are not considered nutrients but are called phytochemicals -means plant chemical -substances in plants that may affect health BENEFITS OF PHYTOCHEMICALS -people who eat tomatoes and processed tomato products produce lycopene(a compound that may reduce prostate cancer risk) which is associated with a decreased risk of chronic diseases.

Potassium

-potassium affects blood pressure SOURCES -veggies and fruits, spinach, potatoes, and melons are some important dietary sources DEFICIENCY/TOXICITY -deficiency is a likely factor in hypertension risk, especially when coupled with high sodium intake -low intake can disrupt acid-base balance in the body and contribute to bone and kidney loss

Antioxidants

-substances that can interfere with the damaging effects of free radicals-which may explain their beneficial effects

Functional Foods

-widely considered to be a food or food component that provides a health benefit beyond basic nutrition

Bioavailability

A measure of the extent to which a nutrient becomes available to the body after ingestion and thus is available to the tissues

Phosphorus

DEFICIENCY -its so common in foods that only near total starvation causes deficiency

Food additives

DIRECT -added to a food for a specific reason 1. to maintain product consistency 2. to improve or maintain nutritional value 3. to keep the food appetizing and wholesome 4. to provinde leavening or control acidity and alkalinity 5. to enhance flavor or give a desired flavor INDIRECT -substances that unintentionally become part of the food in trace amounts

Riboflavin(B2)

FUNCTION -apart of two coenzymes: flavin mononucleotide and flavin adenine dinucleotide -the coenzymes are required in reactions that extract energy from glucose, fatty acids, and amino acids -supports the antioxidant activity of the enzyme glutathione peroxidose -when riboflavin contains co enzymes they participate in reactions that remove ammonia during the deamination of some amino acids SOURCES -grain products, eggs and organ means are good sources DEFICIENCY -overt riboflavin is now rare -long-term use of sedatives and other barbiturates accelerates liver breakdown of riboflavin and contributes to deficiency TOXICITY - no reports

Niacin(B3)

FUNCTION -niacin forms a part of crucially important coenzymes that participate in at least 200 metabolic pathways -plays a key role in energy metabolism -the body needs niacin to synthesize fatty acids SOURCES -mushrooms, liver, and seafood are good sources of niacin DEFICIENCY -Pellagra is the disease of sever niacin deficiency -deficiencies of other nutrients such as iron, riboflavin, and B6 can contribute to the damage TOXICITY -for adults, the UL for niacin is 35ml per day from fortified foods, supplements, and medications -the principal side effects are flushing, related itching, and tingling

Folate

FUNCTIONS -As a coenzyme folate is crucial to DNA synthesis and cell division, amino acid metabolism, and the maturation of red blood cell and other cells makes folate essential for healthy embryonic development -good folate status in early pregnancy greatly reduces the risk of birth defects called neural tube defects. SOURCES -dark green leafy veggies, asparagus, broccoli, orange juice, and wheat germ are good sources DEFICIENCIES -Approximately 10% of the U.S population may have insufficient folate stores -many scientists believe that folate deficiency is the most prevalent of all vitamin deficiencies -in developed countries, folate deficiency has been associated with people who have poor nutrition

Pantothenic acid

FUNCTIONS -a component of coenzyme A, which in turn is part of acetyl CoA, a compound that sits at the crossroads of energy-generating and biosynthetic pathways. DEFICIENCIES -virtually nonexistent TOXICITIES -high intakes have no apparent adverse effects

Biotin

FUNCTIONS -like the other B vitamins biotin acts as a coenzyme in dozens of reactions SOURCES -cauliflower, liver, peanuts, and cheese are good sources DEFICIENCIES -deficiency is rare -eating raw eggs, could produce biotin deficiency TOXICITY -high doses of biotin do not appear toxic, and no UL for biotin has been est.

Selenium

FUNCTIONS -most selenium joins up with one of two amino acids, methionine or cysteine DEFICIENCY/TOXICITY -can be seen where soil selenium concentrations are low

Iron

FUNCTIONS -oxygen transport, enzymes, immune function, and brain function SOURCES -beef is an excellent source DEFICIENCY -most common -females and infants are particularly vulnerable -three stages: body depletes iron stores, body depletes its supply iron in circulating transferrin, and anemia TOXICITY -leading cause of poisoning deaths in children -in hereditary hemochromatosis, a genetic defect causes excessive iron absorption and chronic iron overload -men are more vulnerable than women

Vitamin E:

FUNCTIONS -vitamin E's most well-known function is an antioxidant -it protects vulnerable polyunsaturated lipids in cell membranes, in the blood, and elsewhere throughout the body -numerous studies have suggested that dietary factors such as intakes of antioxidant vitamins, including vitamin E may lower the risk of some chronic diseases, especially heart disease SOURCES -alpha-tocopherol is present in appreciable amounts only in foods such as nuts, some seeds, and vegetable oils -whole-grain products provide vitamin E and wheat germ oil has one of the highest vitamin E concentrations -although most Americans eat a diet relatively rich in soybean oil, only about 10% is alpha-tocopherol, the active form of vitamin E -cooking, processing, and storage can reduce the vitamin E content of foods DEFICIENCY -overt vitamin E is so rare in humans that the Food and Nutrition Board could not use signs of deficiency as a basis for estimating dietary requirements -it occurs mostly in people with fat malabsorption or rare genetic disorders TOXICITY -for a fat-soluble vitamin, vitamin E non toxic and adverse effects have not been found from consuming foods rich in vitamin E -large supplement amounts may cause an increased risk of bleeding

B6

FUNCTIONS -without adequate B6, all amino acids become essential-the body can not make them and must get from food -B6 also helps make glucose from amino acids and helps release glucose from glycogen -vitamin B6, folate, and vitamin B12 work in concert to lower blood levels of the amino acid homocysteine SOURCES -good sources include meat, fish, or poultry DEFICIENCIES -overt vitamin B6 deficiency is rare, although some medications used for parkinson's disease and asthma can cause deficiency -excessive alcohol interferes with the vitamins absorption and its coenzyme activities worsening B6 deficits created by the alcoholics poor diet -overt vitamin B6 deficiency produces a skin rash, anemia and also disrupts nervous system activity TOXICITY -vitamin B6 are not without risk and can cause subtle neurological damage -high-dose B6 has been used for carpal tunnel syndrome- a wrist injury that causes painful tingling in hands and fingers

Thiamin(B1)

FUNCTIONS -works as a coenzyme in reactions that produce energy -as the vitamin component of the coenzyme thiamin pyrophosphate, thiamin helps reactions that break down glucose, make RNA and DNA, or produce energy-rich molecules that power protein synthesis SOURCES -legumes, some nuts and seeds, and some types of fish and seafood are good sources DEFICIENCY -the poor and elderly make be at risk of deficiency due to inadequate energy intake or consumption of nutrient-poor foods TOXICITY no reports

Zinc

FUNCTIONS -zinc and enzymes-helps provide structural integrity -zinc and gene regulation- -zinc and immune system-vital to a vigorous immune system and is essential to the proper development and maintenance of the immune system SOURCES -zinc is usually abundant in foods that are good sources of protein DEFICIENCY -uncommon in the U.S -zinc from cereal is poorly absorbed -symptoms of moderate to severe zinc deficiency include poor growth, delayed or abnormal sexual development, diarrhea, etc. TOXICITY -chronic supplementation with too much zinc may cause acute adverse effects

Calcium

FUNCTIONS bone structure- most bone calcium is part of hyroxyapatite- a hard, crystalline complex of calcium and phosphorus that surrounds collagen fibers -our bones undergo constant remodeling by two types of bone cells-osteoblasts and osteoclasts -osteoblasts- the construction team -osteoclasts- demolition team -together they determine how the bones grow and change overtime -bone mineralization is greatest while children are growing taller CALCIUM, MUSCLE, AND METABOLISM -calcium has a central role in muscle contractions, because the flow of calcium ions inside muscle cells causes muscles to contract or relax -calmodulin is a calcium-sensing protein found throughout the body -blood cannot clot without calcium -nerve cells need calcium to transmit signals SOURCES -nonfat milk and yogurt are good sources providing high calcium DEFICIENCY -low intake increases risk of cardiovascular disease, hypertension, colon cancer, and obesity

Supplement Spotlight

HEALTH CLAIMS -as consumer choices continue to expand and the abundance of functional foods and supplements increases, products that make exaggerated health claims will continue to mislead consumers about their benefits -although many foods and products have legitimate functional benefits, many people put their money and hopes for good health into unneeded functional foods and supplement products that make misleading health claims with little or no scientific evidence of effectiveness -oatmeal with an adequate amount of beta-glucan fiber can highlight its benefit in reducing the risk of heart disease STRUCTURE/FUNCTION CLAIMS -structure/function claims on conventional or functional foods must be based on the food's nutritive value -many manufacturers are making claims about non-nutrients in foods and their effects on body structure of function NUTRIENT CONTENT CLAIMS - REGULATORY AGENCIES AND THEIR ROLE -FTC- they are responsible for ensuring that advertisements and commercials are truthful and do not mislead -FDA-has primarily responsibility for regulating labeling and content of dietary supplements under the federal food, drug and cosmetic act -dietary supplements include vitamins, minerals, herbs, botanicals,etc.

Mega Dose

MEGA DOSES IN CONVENTIONAL MEDICAL MANAGEMENT -situations where a physician may prescribe a vitamin/mineral at megadose levels: 1. when a medication dramatically depletes or destroys the stores or blocks the functions of vitamins/minerals 2. people with malabsorption syndromes such as cystic fibrosis often take large nutrient doses to compensate for nutritive losses, etc. MEGA DOSING BEYOND CONVENTIONAL MEDICINE: ORTHOMOLECULAR NUTRITION -achieving the optimal nutrient levels in the body DRAWBACKS OF MEGA DOSES -when taken without recommendation or prescription from a qualified health professional they can cause problems

Iodine

SOURCES -egg and oatmeal are good sources DEFICIENCY -causes hypothroidism, low levels of thyroid hormones -the most apparent sign is a goiter- and enlarged thyroid gland in the neck TOXICITY -large amounts inhibit synthesis of thyroid hormone -overzealous supplementation is the most common cause of the toxicity

Chromium

SOURCES -good sources include grape and orange juice, processed meats, whole grains, green beans, broccoli, and spices DEFICIENCY/TOXICITY -the only known cases of chromium toxicity are from airborne chromium compounds in industrial settings -200 micrograms of inorganic chromium appears to be a safe supplement dose -supplementation with chromium has been shown to reduce risk factors for type 2 diabetes and cardiovascular disease and aid in mild weight loss in obese and overweight individuals

Magnesium

SOURCES -spinach, brown rice, and peanut butter DEFICIENCY -associated with alcoholism because alcohol increases urinary magnesium excretion

Manganese

SOURCES -tea, nuts, cereals, and some fruits are the best food sources DEFICIENCY/TOXICITY -most people are not a risk

Copper

SOURCES -the richest food sources for copper include organ meats, shellfish, nuts, and seeds, etc. DEFICIENCY -rare and occurs most often in infants born prematurely -reduces production of red and white blood cells -cause bone abnormalities TOXICITIES -nontoxic

Vitamin A:

Vitamin A is crucial for vision, maintaining healthy cells, fighting infections and bolstering immune function, and for promoting growth and development. FUNCTIONS: VISION:DAY/NIGHT -Allows night vision ad color vision by actually becoming a functioning part of the retina -light entering the eye and striking the retina splits rhodopsin, causing it lose color as it releases opsin and vitamin A -if vitamin A levels are low, the body cannot re-form rhodopsin, and night-blindness results color vision requires vitamin A -A prolonged lack of vitamin A impairs color vision, but because it affects rod cells before cone cells, night blindness emerges first VITAMIN A IN CELL PRODUCTION AND DIFFERENTIATION: -When your body needs to make the proteins that from new cells or other protein compounds, vitamin A plays a role in directing protein production -vitamin A works in cell differentiation, the process that causes immature, characterless cells to mature into specific kinds of cells -Vitamin A plays a role in building and maintaining tissues throughout the body VITAMIN A AND SKIN: -Replacing epithelial cells requires vitamin A VITAMIN A AND IMMUNE FUNCTION -By helping to maintain the health of epithelial tissues vitamin A plays an important role in the integrity of the immune system -to produce immune cells your body needs vitamin A VITAMIN A AND REPRODUCTION -vitamin A affects both male and female -it helps maintain fertility in women needed for sperm production in men VITAMIN A AND BONES -vitamin A helps produce bone cells needed for growth and is required for bone remodeling -lack of vitamin A in a growing child disrupts bone remodeling and interferes with the development of immature bone cells -too much has been linked to bone loss and an increase in risk of fractures FOOD SOURCES -most dietary vitamin A comes from animal food sources as preformed vitamin A -liver is the richest source of vitamin A -low-fat milk is fortified- good source of vitamin A -plant foods, especially yellow-orange vegetables and fruits, contain provitamin A carotenoids, mainly beta- carotene DEFICIENCY: -vitamin A deficiency occurs alongside general protein-energy malnutrition in infants and young children -vitamin A deficiency interacts with other nutrient deficiencies and with infection, worsening respiratory infections or diarrhea and causing countless deaths THE EYES -early treatment can rapidly correct night blindness, an early symptom of vitamin A deficiency THE SKIN AND OTHER EPITHELIAL CELLS hard, bumpy, scaly skin thats doesn't go away is an early symptom of vitamin A deficiency -the deficiency disrupts epithelial cell production, and the skin's hair follicles become plugged with keratin -sperm production slows and female fertility declines IMMUNE FUNCTION -with too few immune cells to mount an effective attack, the invading microorganisms can cause severe, even fatal, diarrhea or respiratory infection -Hyperkeratinization near sensory receptors causes a loss of taste and smell, which in turn can cause loss of appetite and weight TOXICITY -vitamin A toxicity has a wide range of symptoms, both subtle and overt, including fatigue, vomiting, abdominal pain, bone and joint pain, loss of appetite, skin disorders, etc. birth defects are cleft palate, heart abnormalities, and brain malfunction

Vitamin D:

fat-soluble vitamin called the sunshine vitamin FUNCTIONS -considered both a vitamin and a hormone -keeps bones healthy -regulator -vitamin D has a role in preventing cancer cells from dividing and has anti-inflammatory properties -involved in the regulation of insulin formation and secretion, which suggest s a role in blood sugar maintenance and the development of type 2 diabetes mellitus REGULATION OF BLOOD CALCIUM LEVELS -the primary regulatory role of 25(OH)D is to maintain blood calcium and phosphorus levels within a normal range -it acts in concert with two other hormones: parathyroid hormone and calcitonin -levels of these three hormones continually rise and fall, adjusting blood calcium absorption, and the flow of calcium into and out of bone SOURCES -get vitamin D from exposure to sunlight, our diets , and dietary supplements -sensible sun exposure can provide an adequate amount of vitamin D -the major sources of vitamin D are fortified foods, mainly fortified milk and fortified breakfast cereals DEFICIENCY -approximately 1 billion people worldwide in all age and ethnic groups have inadequate levels of vitamin D in their blood -vitamin D deficiency damages bones and contributes to a wide range of acute and chronic conditions -babies with the deficiency have soft, weak bones that bend and bow under their weight as they start to walk-rickets -in adults, vitamin D deficiency causes osteomalacia, or soft bones -vitamin D deficiency worsens osteoporosis -vitamin D deficiency causes muscle weakness and increases the risk of bone fractures TOXICITY -although sun exposure does not cause vitamin D toxicity, supplement megadoses are highly toxic -because some people are adversely affected by elevated levels of vitamin D, high dose supplementation should be used only after careful consideration and consultation with a knowledgeable medical professional -if prolonged, the body deposits excess calcium in soft tissues, causing pain and organ damage -other symptoms, nausea, vomiting and loss of appetite

Delaney Clause

food additives and color cannot be approved if they cause cancer in humans or animals

Ultratrace

iodine, fluoride, manganese, molybdenum, and selenium -are found in the body in minuscule amounts

Carotenoids:

plant pigments that give the deep yellow, orange, and red colors to fruit and vegetables such as apricot, carrots, and tomatoes. -major carotenoids are alpha-carotene, beta-carotene, lutein, zeaxanthin, cryptoxathin, and lycopene. FUNCTIONS -are not essential -beta-carotene and other carotenoids function as potent antioxidants- substances that can interfere with the damaging effects of free radicals- highly unstable, reactive compounds -which may explain there beneficial effects CAROTENOIDS AND VISION -higher intakes of carotenoids, especially lutein and zeaxanthin, from foods or supplements may play an important role in protecting vision CAROTENOIDS AND CANCER -high intakes lower risk of cancer FOOD SOURCES -good sources of beta-carotene include carrots, winter squash, sweet potatoes, and some orange colored fruits like cantaloupe and mango -your body generally absorbs only 20-40% of the carotenoids you eat; however, this proportion drops to 10% or less as the amount of carotenoids you eat increases -dietary fat increases absorption TOXICITY -extremely large intakes of carotenoid-rich foods have not been associated with toxic effects

Vitamin K

vitamin K is essential for blood clotting FUNCTIONS -many reactions in this coagulation cascade require vitamin K and calcium -vitamin K helps with bone formation, increases bone strength, and decreases fractures -low levels of vitamin K are associated with age-related bone loss SOURCES -we obtain vitamin K from two sources: food(mostly plant food) and bacteria living in our colons dietary vitamin K is absorbed in the small intestines, and vitamin K produced by bacteria is absorbed in the colon -plant foods are our primary source DEFICIENCY -In adults, vitamin K is rare and usually occurs in people with malabsorption problems -newborn babies lack vitamin K-producing intestinal bacteria TOXICITY -because the excretes vitamin K much more rapidly than other fat-soluble vitamins, vitamin K toxicity from food is rare