CH. 7 - The Vitamins

What are the fat-soluble vitamins?

Vitamins A, D, E, K

WHat are the chief functions of vitamin K?

Synthesis of blood-clotting proteins and bone proteins

TRUE or FALSE Active forms of vitamin A that are readily absorbed in the body are only found in foods derived from animals.

TRUE

Why are vitamin precursors important?

They are found in foods and transformed into active vitamins by the body (vitamin potential in food).

What is the Toxicity characteristic of fat-soluble vitamins?

Toxicities are likely from supplements but occur rarely from food.

What is the Toxicity characteristic of water-soluble vitamins?

Toxicities are unlikely but possible with high doses from supplements.

What is the Transport and Storage characteristic of water-soluble vitamins?

Travel freely in watery fluids; most are not stored in the body.

What is the Transport and Storage characteristic of fat-soluble vitamins?

Travel with protein carriers in watery body fluids; stored in the liver or fatty tissues.

What are the chief functions of vitamin A?

Vision; maintenance of cornea, epithelial cells, mucous membranes, skin; growth; regulation of gene expression; reproduction; immunity

What are the water-soluble vitamins?

Vitamin Bs and C

What are the key vitamins for bone health?

Vitamin D, K, C

epithelial tissue

the layers of the body that serve as selective barriers to environmental factors. Examples are the cornea, the skin, the respiratory tract lining, and the lining of the digestive tract.

What is special about vitamin D for humans?

our skin makes vitamin D when exposed to sunlight! :)

What occurs when people consume too much vitamin D?

overdoes raises blood calcium and damages soft tissues

What are some consequences of vitamin A overdose?

overstimulated cell division, skin rashes, hair loss, hemorrhages, bone abnormalities, birth defects, fractures, liver failure, and death.

Is rickets an example of a primary or secondary disease? Why?

primary disease (can be treated with vitamin D supplementation).

What does the body do when the bloodstream is low on calcium?

pulls from calcium in the skeleton, increases the digestive tract's absorption of calcium, and the kidneys recycle calcium that would just be excreted in the urine

What does the acronym RAE stand for?

retinol activity equivalents

What is the disease that is characterized by an inadequate mineralization in a child's skeleton?

rickets

erythrocyte hemolysis

rupture of the red blood cells that can be caused by vitamin E deficiency (erythro means "red"; cyte means "cell"; hemo means "blood"; lysis means "breaking"). The anemia produced by the condition is hemolytic (HEE-moh-LIT-ick) anemia.

night blindness

slow recovery of vision after exposure to flashes of bright light at night; an early symptom of vitamin A deficiency.

Would someone with lighter or darker skin be more at risk for developing a vitamin D deficiency?

someone with dark skin is more at risk because they have more melanin, which prevents them from absorbing vitamin D as much as someone with lighter skin (less melanin)

What are good sources of vitamin K?

soybeans, spinach, cabbage, salad greens, asparagus, kale, black eyed peas

What are good food sources of vitamin A?

spinach, sweet potato, carrots, fortified milk, apricots, bok choy, beef liver,

What are good sources of vitamin D?

sunlight, salmon or mackerel, sardines, enriched cereal, tuna, fortified milk, cod-liver oil, mushrooms grown in light

What are good sources of vitamin C?

sweet potato, grapefruit, brussel sprouts, sweet red pepper, bok choy, strawberries, broccoli, green pepper, orange juice

What is osteomalacia?

the adult expression of vitamin D-deficiency disease, characterized by an overabundance of unmineralized bone protein (osteo means "bone"; mal means "bad"). Symptoms include bending of the spine and bowing of the legs.

Where is the active (usable) form of vitamin D synthesized in the body?

the kidneys

What is the UL for vitamin E (specifically the form alpha-tocopherol)?

1,000 micrograms

What are the two ways that you can measure the amount of a vitamin precursor in food?

1. IU 2. micrograms

What are the different stages of blindness that someone can experience from vitamin A deficiency (not including night blindness).

1. keratinization (accumulation of keratin in eye tissue) 2. xerosis (drying cornea) 3. xerophthalmia (permanent blindness)

What are the three forms of vitamin A found in the body?

1. retinol 2. retinal 3. retinoic acid

What is the UL for vitamin D?

100 micrograms

How many micrograms of beta-carotene supply 1 microgram of retinol to the body?

12 micrograms of beta-carotene

What is the UL for vitamin C?

2,000 micrograms

What is the UL for vitamin A?

3,000 micrograms/day

What occurs when there is a vitamin D deficiency?

Abnormal bone growth resulting in rickets in children, osteomalacia in adults; malformed teeth; muscle spasms

What is the Absorption characteristic of water-soluble vitamins?

Absorbed directly into the blood.

What is the Absorption characteristic of fat-soluble vitamins?

Absorbed like fats, first into the lymph and then into the blood.

What occurs when someone has a toxic level of vitamin A?

Acute (single dose or short-term): nausea, vomiting, headache, vertigo, blurred vision, uncoordinated muscles, increased pressure inside the skull, birth defects. Chronic: birth defects, liver abnormalities, bone abnormalities, brain and nerve disorders

What are the chief functions of vitamin E?

Antioxidant (protects cell membranes, regulates oxidation reactions, protects polyunsaturated fatty acids)

What occurs when there is a toxicity of vitamin E?

Augments (increase) the effects of anticlotting medication; aka trouble with excessive bleeding, cannot clot blood

What are all of the B vitamins?

B1 - Thiamin B2 - Riboflavin B3 - Niacin Folate B6 B12 Biotin Pantothenic acid

What happens when vitamin C is taken in toxic amounts?

Nausea, abdominal cramps, diarrhea; rashes; interference with medical tests and drug therapies; in susceptible people, aggravation of gout or kidney stones

Deficiency in the water-soluble vitamins, ______ and ______, contribute to anemia, and a deficiency in ______ causes pellagra.

Blank 1: B12 Blank 2: folate Blank 3: niacin

Vitamins have many functions throughout the body. For example, vitamins C and E function as ______, the B vitamins functions as ______, and vitamin D is important for ______.

Blank 1: antioxidants Blank 2: coenzymes Blank 3: calcium regulation

Increased activation of vitamin D will result in ______ absorption of calcium in the kidneys and ______ risk of inadequate bone mineralization.

Blank 1: increased Blank 2: decreased

A ______ is a lack or shortage of a particular vitamin, and prolonged insufficiency can eventually lead to a ______, characterized by harmful symptoms.

Blank 1: vitamin deficiency Blank 2: vitamin deficiency disease

What are the key minerals for bone health?

Calcium, Phosphorous, Magnesium, and Fluoride

What are the chief functions of vitamin C?

Collagen synthesis (strengthens blood vessel walls, forms scar tissue, provides matrix for bone growth), antioxidant, restores vitamin E to active form, supports immune system, boosts iron absorption

What happens when there is a toxic amount of vitamin D in the body?

Elevated blood calcium; calcification of soft tissues (blood vessels, kidneys, heart, lungs, tissues of joints), excessive thirst, headache, nausea, weakness

TRUE or FALSE B12 supplements mask a folate deficiency.

FALSE Folate supplements can mask a B12 deficiency.

What occurs when someone has a toxic level of vitamin A's precursor beta-carotene?

Harmless yellowing of skin

What occurs when there is a deficiency in vitamin K?

Hemorrhage (blood cells exploding); abnormal bone formation

What are the chief functions of vitamin D?

Mineralization of bones and teeth (raises blood calcium and phosphorus by increasing absorption from digestive tract, withdrawing calcium from bones, stimulating retention by kidneys)

What is the Requirements characteristic of water-soluble vitamins?

Needed frequently (even daily) because the body does not store most of them to any extent.

What is the Requirements characteristic of fat-soluble vitamins?

Needed in periodic doses (weekly or even monthly) depending on the extent of body stores.

What happens when there is a vitamin A deficiency?

Night blindness, corneal drying (xerosis), and blindness (xerophthalmia); impaired growth; keratin lumps on the skin; impaired immunity

What is the Excretion characteristic of fat-soluble vitamins?

Not readily excreted; tend to build up in the tissues.

What happens when someone has a toxic amount of vitamin K?

Opposes the effects of anticlotting medication

What is the Excretion characteristic of water-soluble vitamins?

Readily excreted in the urine.

What occurs when someone has a deficiency in vitamin E?

Red blood cell breakage, nerve damage

What occurs when someone has a deficiency in vitamin C?

Scurvy, with pinpoint hemorrhages, fatigue, bleeding gums, bruises; bone fragility, joint pain; poor wound healing, frequent infections

macular degeneration

a common, progressive loss of function of the part of the retina that is most crucial to focused vision. This degeneration often leads to blindness.

prooxidant

a compound that triggers reactions involving oxygen.

What is a common cause of of macular degeneration?

a diet that lacks carotenoids (orange and dark green, leafy vegetables)

What is tocopherol?

a kind of alcohol. The active form of vitamin E is alpha-tocopherol.

IU (international unites)

a measure of fat-soluble vitamin activity sometimes used in food composition tables and on supplement labels.

retinol activity equivalents (RAE)

a new measure of the vitamin A activity of beta-carotene and other vitamin A precursors that reflects the amount of retinol that the body will derive from a food containing vitamin A precursor compounds.

What is osteoporosis?

a reduction of the bone mass of older people in which the bones become porous and fragile (osteo means "bones"; poros means "porous") ; also known as adult bone loss.

What is a coenzyme?

a small molecule that works with an enzyme to promote the enzyme's activity. Many coenzymes have B vitamins as part of their structure (co means "with").

What is oxidative stress?

a theory of disease causation involving cell and tissue damage that arises when free radical reactions exceed the capacity of antioxidants to quench them.

Which of these situations or conditions could contribute to a vitamin D deficiency? a) living in a region without a lot of sunlight b) having a lighter skin pigmentation c) spending a lot of time outdoors d) having chronic kidney disease

a) and d)

Which symptom is not associated with vitamin B deficiency? a. increased appetite b. nausea c. muscle pain d. forgetfulness e. irritability

a) increased appetite

Which characteristic is LEAST likely to apply to a fat-soluble vitamin? a. easily absorbed and excreted in urine b. toxic in excess c. dissolves in lipids d. commonly found in foods that contain fat e. requires bile for absorption

a. easily absorbed and excreted in urine

A woman who is on a low-carbohydrate diet for weight loss may have difficulty maintaining an adequate level of the B vitamins thiamin, riboflavin, niacin, and folate. What characteristic of her diet would cause this? a. exclusion of grains and cereals b. exclusion of fruits c. exclusion of dairy d. exclusion of meat and fat e. exclusion of starchy vegetables

a. exclusion of grains and cereals

The need for vitamin E rises as people consume more of what because it requires antioxidant protection by the vitamin? a. polyunsaturated fat b. saturated fat c. fried food d. meat e. trans fat

a. polyunsaturated fat

What is the main function of vitamin K?

activate proteins that help clot blood

beta-carotene

an orange pigment with antioxidant activity; a vitamin A precursor made by plants and stored in human fat tissue.

Where is vitamin A's ACTIVE form found?

animal foods

What are free radicals?

atoms or molecules with one or more unpaired electrons that make the atom or molecule unstable and highly reactive. occurs from oxidative damage

Which of the following is LEAST likely to contribute to cases of rickets in the United States? a. increased time spent indoors b. increased physical activity in organized sports c. dark skin pigmentation d. use of UV-blocking sunscreen e. a preference for soft drinks over milk in adolescents

b. increased physical activity in organized sports

Why are overweight people at risk of having a vitamin D deficiency?

because it takes a lot more blood to circulate through the body, which can dilute the vitamin D

Why do babies need an injection of vitamin K at birth?

because their intestinal bacteria has not developed enough to synthesize vitamin K and this can lead to many health problems in the baby such as hemorrhaging.

What is vitamin A's precursor?

beta-carotene

Which food item has the highest amount of vitamin C? a. ½ cup rice b. 1 cup yogurt c. 1 ounce steak d. ½ cup sweet red pepper e. ½ cup carrots

d. ½ cup sweet red pepper

Given what you know about the characteristics of a deficiency disease, which of the following would be considered a deficiency disease resulting from inadequate levels of vitamin D? (multiple answers) a) cardiovascular disease b) skin cancer c) osteomalacia d) rickets e) type 1 diabetes

c) and d)

Which individual has a valid reason to take a vitamin/mineral supplement? a. someone who believes that food grown on today's soils lack nutrients b. someone who is stressed and does not get enough exercise c. someone who is addicted to drugs or alcohol d. someone who is feeling tired and wants a supplement to provide energy e. someone who does not like to eat vegetables

c. someone who is addicted to drugs or alcohol

Which vitamin is mismatched with its deficiency? a. vitamin K - excessive bleeding b. vitamin C - scurvy c. vitamin D - pernicious anemia d. thiamin - beriberi e. niacin - pellagra

c. vitamin D - pernicious anemia

What mineral goes hand in hand with vitamin D?

calcium

What is vitamin D important for?

calcium regulation

The B vitamins function as what?

coenzymes

What is vitamin C important for?

collagen synthesis

precursors

compounds that serve as starting materials for other compounds. In nutrition, vitamin precursors are compounds that can be converted into active vitamins. Also called provitamins.

dietary antioxidants

compounds typically found in plant foods that counteract the adverse effects of oxidation on living tissues. The major antioxidant vitamins are vitamin E, vitamin C, and beta-carotene. Many phytochemicals are also antioxidants.

What destroys vitamin E in food?

cooking! vitamin E is very sensitive to heat

If you eat a food that contains a large dose of thiamin and riboflavin, what will most likely happen to the thiamin and riboflavin? a. They will increase destruction of free radicals in the body. b. They will be stored in the body tissues for later use as needed. c. They will promote the production of red blood cells. d. They will be excreted if not used on the day they are absorbed. e. They will be stored in fat cells, which can lead to toxicity.

d. They will be excreted if not used on the day they are absorbed.

Which statement is true of vitamin C? a. Vitamin C is challenging to obtain from food. b. Vitamin C is stored in fat. c. Vitamin C impedes the absorption of iron in food. d. Vitamin C acts as an antioxidant.

d. Vitamin C acts as an antioxidant.

All of these statements are true EXCEPT which one? a. Fat-soluble vitamins require bile to be absorbed in the body. b. Fat-soluble vitamins are stored, and therefore overconsumption may lead to toxicity. c. Vitamins A, D, E, and K are fat-soluble. d. Vitamins are essential, caloric nutrients that are needed in tiny amounts.

d. Vitamins are essential, caloric nutrients that are needed in tiny amounts.

Which statement regarding water-soluble vitamins is FALSE? a. Foods never deliver toxic doses of the water-soluble vitamins. b. Some water-soluble vitamins are destroyed when exposed to light, heat, or oxygen during processing. c. Water-soluble vitamins are easily excreted in the urine. d. Water-soluble vitamins easily dissolve and drain away with cooking water. e. Water-soluble vitamins are easily absorbed and stored in the liver.

e. Water-soluble vitamins are easily absorbed and stored in the liver.

Current recommendations for fruit and vegetable intakes are for us to consume a variety from each category on a daily basis. What are the two vitamins that are abundant in leafy greens and citrus fruits, as well as other fruits and vegetables?

folate and vitamin C

What is another way besides food that vitamin K can be obtained?

intestinal bacteria synthesizes vitamin K! :)

How does vitamin E prevent free radicals from damaging the body?

it is an antioxidant, which keeps free radicals under control

According to the animation, the ________ is the organ where the conversion of inactive vitamin D is converted to calcidiol.

liver

carotenoids

members of a group of pigments in foods that range in color from light yellow to reddish orange and are chemical relatives of beta-carotene. Many have a degree of vitamin A activity in the body.

How do you convert IU to micrograms?

multiply the micrograms times 40

retinol

one of the active forms of vitamin A made from beta-carotene in animal and human bodies; an antioxidant nutrient. Other active forms are retinal and retinoic acid.

What is ascorbic acid?

one of the active forms of vitamin C (the other is dehydroascorbic acid); an antioxidant nutrient.

vitamins

organic compounds that are vital to life and indispensable to body functions but that are needed only in minute amounts; essential, noncaloric nutrients.

rhodopsin

the light-sensitive pigment of the cells in the retina; it contains vitamin A (opsin means "visual protein").

How is vitamin D produced through the sun converted into a substance the human body can use?

the skin absorbs the sun and creates a vitamin D precursor, which is then converted from the inactive precursor to the active form of vitamin D in the kidneys and liver

What is scurvy?

the vitamin C-deficiency disease.

What is rickets?

the vitamin D-deficiency disease in children; characterized by abnormal growth of bone and manifested in bowed legs or knock-knees, outward-bowed chest deformity (pigeon chest), and knobs on the ribs.

What occurs when someone consumes too much vitamin A, specifically beta-carotene?

their skin can turn orange

What is vitamin A important for?

vision

A ______ is an organic compound that must be obtained from the diet and is needed to sustain life.

vitamin

What was the first fat-soluble vitamin to be recognized?

vitamin A

Which vitamin supplement is known to cause malformations of a fetus?

vitamin A

Which vitamins are classified as water-soluble vitamins?

vitamin Bs and C

Which vitamin has the most potential to be toxic when too much is consumed?

vitamin D

You have a friend who eats a lot of highly processed foods, fast foods, and convenience foods, but does drink fortified milk. What type of deficiency is your friend at risk for developing?

vitamin E deficiency

What are the major antioxidant vitamins?

vitamin E, C, and beta-carotene (vitamin A precursor)

Which vitamin's main role is to help activate proteins that help blood clot?

vitamin K

What are some good sources of vitamin E?

wheat germ, safflower oil, sunflower seeds, canola oil, mayonnaise

What causes jaundice?

when people have a toxic level of vitamin K in their system

What is jaundice?

yellowing of the skin due to spillover of the bile pigment bilirubin (bill-ee-ROO-bin) from the liver into the general circulation.