110 terms

Human Nutrition EXAM 3

What is Magnesium?
Major Mineral
Functions of magnesium
Aids in many enzyme reactions; potassium and calcium metabolism; proper nerve and cardiac functions; insulin release from the pancreas; may dilate arteries (decrease blood pressure, decrease CVD risk); may prevent heart rhythm abnormalities
Does Magnesium Deficiency develop quickly or slowly and why?
slowly because it is stored in the body
What can cause Magnesium loss?
chronic heavy perspiration, long-standing diarrhea or vomiting, and alcoholism because dietary intake may be poor and it increases magnesium excretion in the urine
What are some sources of Magnesium?
Whole grains, vegetables, nuts, seeds, hard tap water, dairy, chocolate, meat
Magnesium's absorption is based on what and what percent is normal?
Absorption is based on bodys needs and is normally 40-60 percent
What organ regulates blood concentration of magnesium?
the kidneys
How much magnesium is stored in the bones?
60 percent
What does Magnesium deficiency cause (symptoms)?
irregular heartbeat, weakness, muscle spasms, disorientation, nausea, vomiting, seizures
What causes magnesium toxicity?
Kidney failure, overuse of medications such as antacids and laxatives
What are vitamins?
essential organic substances
What classifys something as essential?
the body cannot produce them in enough quantity for health, it produces deficiency symptoms when its missing from the diet, and its carbon-containing
Do vitamins yield energy?
Are vitamins needed in large or small amounts?
where are vitamins supplied from?
both plant and animal foods
do vitamin supplements work?
Yes, just as equally well (in general)
How were vitamins named?
in order of discovery (a, b, c...)
what vitamin was thought to be one but turned out to be many?
Can vitamins be dropped if they were found to be inessential and if so, which one was?
yes, vitamin P
What are the two basic functions of vitamins?
Facilitate energy-yielding chemical reactions and function as co-enzymes
what are the two vitamin categories and what vitamins fall into which groups (A,B's,E,K,C,D)?
Fat-soluble (A,D,E,K) and Water Soluble (B's, C)
Are fat soluble vitamins readily excreted? any exceptions?
No except vitamin K
Should vitamins be consumed daily?
Are water vitamins generally stored in the body? Any exceptions?
no except vitamins B-6 and B-12
Which group of vitamins are more like to cause toxicity?
Fat-soluble vitamins
Can Water soluble vitamins cause toxicity?
yes some can
Vitamin toxicity is most likely due to what?
What can decrease vitamin content in foods?
improper storage, excessive cooking, exposure to light, heat, air, water, and alkalinity
How are fat-soluble vitamins absorbed and transported?
along with fat
What group does vitamin A fall into: fat-soluble or water-soluble?
fat soluble
What are vitamin A's preformed "active" forms and where can they be found?
retinoids (retinal, retinol, retinoic acid) and in animal products
What are vitamin A's proformed (precursor of vitamin a) and where can they be found?
carotenoids (beta-carotene, lutein, zeaxanthin) and in plant products
What are the functions of Vitamin A?
promotes vision, prevents drying of the skin and eyes, promotes immune function and resistance to bacterial infection, promotes growth, cardiovascular disease prevention, cancer prevention, and acne medicine
What do carotenoids help stop?
macular degeneration and the risk of cataracts in the eyes
what are some food sources of vitamin A?
spinach, kale, and other dark leafy greens, broccoli, deep orange fruits (apricots, cantaloupe) and vegetables (squash, carrots, sweet potatoes), fortified milk and yogurt, fortified magarine, eggs, liver, fish, and fish oils
What does Vitamin A deficiency cause?
Night blindess, corneal drying (xerosis), softening of the cornea (karatomlalacia), corneal degeneration and blindness (xerophthalmia), and impaired immunity (infections)
What are the symptoms of Vitamin A toxicity?
Bone/muscle pain, loss of appetite, skin disorders, headache, dry skin, hair loss, increased liver size, vomiting, and fetal malformation
Is vitamin D a water-soluble or fat soluble vitamin?
fat soluble
What makes Vitamin D a vitamin?
insufficient sun exposure
Where is vitamin D dervied from and what does that make it?
Cholesterol. it makes it a hormone
how is vitamin D synthesized and what does it depend on?
sun exposure; depending on age, time of day, season, location, and skin color
What are the functions of Vitamin D?
Regulates blood calcium -> bone metabolism (along with the parathyroid hormone, regulates calcium + phosphorus absorption, reduces kidney excretion of calcium , regulates calcium deposition in bones)and influences normal cell development
What is Vitamin D's role in bone formation?
Causes calcium + phosphorus to deposit in the bones, strengthening them
What are the two diseases as a result of Vitamin D deficiency and their definitions?
Rickets (breastfed infants with little sun exposure) and Osteomalacia ("soft bones" or rickets-like disease in adults where bones lose minerals and become porous)
What are some food sources of vitamin d?
fatty fish (salmon, herring), fortified milk, and some fortified cereal
What does Vitamin D Toxicity cause?
over-absorption of calcium (hypercalcemis) increase calcium excretion, calcium deposits in organ and blood vessels, and growth retardation
Can Vitamin D become very toxic? if so, what ages are most vunerable?
yes, infancy and childhood
What kind of vitamin is Vitamin E?
A fat-soluble antioxidant
What does Vitamin E mostly resides in
cell membranes
What are the functions of Vitamin E?
protects double bonds in unsaturated fats and improves vitamin A absorption
What happens in Vitamin E dificiency?
breakdown of cell membranes, hemolysis of RBC's in preterm infants, and nerve degeneration
What are some food sources of Vitamin E?
polyunsaturated plant oils such as margarine, salad dressings, shortenings, and leafy green vegetables, asparagus, tomatoes, wheat germ, whole grains, egg yolks, nuts, and seeds
What are the toxic effects of Vitamin E?
inhibits vitamin K metabolism and anticoagulants, possibly hemorrhage, muscle weakness, headaches, and nausea
Is Vitamin K a fat- or water- soluble vitamin?
What does the 'K' in Vitamin K Stand for?
Is Vitamin K toxicity likely?
What are some food sources of Vitamin K?
Liver, Green leafy vegetables, broccoli, peas, and green beans
Is Vitamin K deficiency likely?
What is Vitamin K synthesized by?
the bacteria in the colon and absorbed
What roles do Vitamin K play (there's 2)?
role in coagulation process and in calcium-binding potential
What is the definition of Hunger?
Physiological state that results when not enough food is eaten to meet energy needs
Malnutrition definition:
Condition of impaired development or function caused by deficiency OR excess
Undernutrition definition is:
failing health that results from long standing dietary intake that is not enough to meet nutritional needs (a form of malnutrition)
Overnutrition is...
excess amount of food leading to over consumption and poor food choices (a form of malnutrition)
Famine is...
extreme shortage of food leading to massive (large scale) starvation in a population
Food Insecurity is...
condition of anxiety about running out of food or money to buy food (963 million)
What are the critical micronutrients missing from diets worldwide?
Iron, Vitamin A (night blindness, no mucus in eye - can cause blindness), Various B Vitamins (e.g., folate), zinc, Iodide
What are the characateristics of Famine?
Large-scale loss of life, social disruption, economic chaos, and human distress
What are the causes of famine?
Crop failure, bad weather, and war/political unrest
What are the characteristics of the initial stage of semistarvation?
no visible clinical signs, may affect reproductive capacity, weakened immune system, depressed lab values, fatigue
What are the effects of semistarvation?
weight loss, fatigue, muscle soreness, irritability, hunger pains, poor concentration and lack of ambition (cognitive effects), decreased heart rate and muscle tone, biochemical abnormalities, SEVERE: deficiency disease(s)
What are the effects of undernutrition during pregnancy?
nutritional needs are higher, fetal devleopment is affected, fetus may deplete maternal nutrient stores, and results in increased risk of death of woman and/or child
What are the effects of undernutrition during fetal and infant stages?
poor growth and development, pre-term delivery with immature lungs and weakened immune system, long-term health problems, and increased health care costs
What are the effects of undernutrition during childhood?
period of rapid growth, permanent brain impairment, stunted growth, impaired motor skills, low resistance to infection, and iron deficiency anemia
What are the characteristics of undernutrition in older adults?
Require nutrient dense foods, many on fixed incomes, many forced to choose between medication or food, lower resistance to infections
What are the two main reasons for undernutrition in the U.S. ?
Poverty and Homelessness
What are some of the federally subsidized programs that suppyly food in the U.S.?
School Lunch Program (1946), Food Stamp program for low income (currently 28 million) -- Now SNAP, School Lunch and Breakfast program provide meals free or reduced cost, WIC, and charitable food pantries
What are the causes of poverty in the U.S?
overabundance of unskilled workers, low paying service jobs, massive lay-offs/unemployment, and increase in # of single parent families
What are the causes of homelessness in the U.S.?
high cost of housing, subsidies for housing decreased, low income families likely to spend more than half their income for rent, release of mentally ill patients, and alcohol/drug abuse
What are problems in the developing world?
extreme imbalances in access to food, war and political unrest, rapid depletion of natural resources, HIV/AIDS (asia and Africa), high external debt, and poor infrastructure
What are the benefits of biotechnology?
synthesis of "super crop" that resists disease, pests, etc, may reduce undernutrition, improve nutritional content, and increase crop yield
what is biotechnology?
genetic engineering (genetically modified organism- GMO)
What are some of the characterisitics of water-soluble vitamins?
they dissolve in water, gnerally readily excreted from body, subject to cooking losses, function as coenzymes, participate in energy metabolism, marginal deficiency more common
Thiamin is which B vitamin?
What is Thiamin senstivie to?
alkalinity and heat
What is Thiamin's coenzyme form used in?
energy metabolism
What disease is caused by Thiamin Dificiency? What are its two kinds?
Beriberi, wet (adema) and dry (poor areas)
What are some food sources of thiamin?
meat, wheatgerm, squash, soy milk, watermelon, fresh orange juice, cooked green peas, based beans, navy beans, and corn
What is Riboflavin?
A coenzyme form that particpates in energy-yielding metabolic pathways
What are the results of Riboflavin deficiency?
Cheilosis, inflammation of mouth and tongue, dermatitis, and sensitivity to the sun
IS Robiflavin toxic or nontoxic?
What are some food sources of riboflavin?
milk/milk products, enriched grains/cereals, eggs, liver, spinach, oysters, and brewers yeast
Niacin or Nicotinamide is what?
A coenzyme form that is used in energy metabolism
What are the three D's associated with Niacin deficiency?
Dermatitist, demetia, and diarrhea
What is Pellagra caused by?
Niacin Deficiency
Can Niacin be toxic?
What are some food sources of Niacin?
Enriched grains, beef, chicken/turkey, and fish; heat stable with little cooking loss
Panthothenic Acid is part of which coenzyme?
What is Pantothenic Acid essential for?
Metabolism of carbohydrate, fat, and protein
Is Pantothenic acid deficiency rare or common?
What are some food sources of Pantothenic Acid?
Meat, Milk, mushrooms, liver, and peanuts
How much of your body weight is wtarer?How much water does muscle contain?
about 73%
How much water does fat contain?
about 20%
Can the body store water?
What are fluids within the cells ?
Intracellular fluid
What is extracellular fluid?
fluid outside the cells
What happens when you have too much water?
"water intoxication", overburden the kidneys (excretion limit/threshold), low blood electrolye concentrations, cells swells (especially in the brain), blurred vision, headache --> death
What is the difference between major and trace minerals? name 2 examples of each
Major minerals require >100mg/day while trace minerals require <100mg/day major: calcium phosphorus, trace: iron, zinc
What are the characteristics of the bioavailability of minerals?
degree of absorption, prescence of binders and fiber, animal products are better absorbed, plants depend on mineral content of soil, refinement lowers mineral content, mineral-mineral and mineral-vitamin competition
Which category of minerals is more toxic?