Test 3: Chapter 7

Describe vitamins

Needed in small amounts

Not an energy source

Individual units rather than long chains

Essential for normal functioning, growth and maintenance

What vitamins are antioxidants

Vitamin E, Vitamin C, Beta-carotene

What are the coenzyme vitamins

The 8 B-vitamins

What vitamins are for bone health

Vitamin A, Vitamin D, Vitamin K

What vitmain is for vision

vitamin A

What vitamin is for blood clotting

Vitamin K

Describe the fat-soluble vitamins

A, D, E, K

Absorbed with fat into the lymphatic system

Stored in larger quantities

Less vulnerable to cooking losses

Describe water-soluble vitamins

B vitamins, and vitamin C

Absorbed into the bloodstream

Stored in small amounts

Vulnerable to cooking losses

What type of vitamins are needed in the diet

Water-soluble vitamins

Where are fat-soluble vitamins accumulated

in the liver and adipose tissue

can be drawn on in time of need

excessive intake can exceed storage capacity and have toxic effects

Describe water-soluble vitamin storage

The body does not store most water-soluble vitamins, need to be apart of diet

Small variations in daily intake does not cause problems

Excess intake is usually harmless but some can be problematic

Describe how the source (animal vs plant) effects vitamins in food

Sunlight, soil/growing conditions, and maturity at harvest

Vitamin content is fairly consistent in animals

Describe how packaging and storage of vitamins effects food

Exposure to light and air

Describe how the level of food processing effects vitamins

more processing= greater loss of vitamins

Describe how cooking can effect vitamins in food

More cooking=greater loss of vitamins

What are the active forms of vitamin A (retinoids)

Retinol (key player)

Retinal

Retinoid acid

What are the precursors of vitamin A (carotenoids)

Carotenoids are colorful plant pigments

Provitamin A compounds are converted into vitamin A by the body

Beta-carotene is a yellow-orange pigment that yields the most vitamin A

Describe the storage and transport of vitamin A

Liver stores about 90% of vitamin A and can store up to a years worth

Remainder found in fatty tissues, lungs, kidneys

Primarily stored as retinyl esters

Retinol-binding protein carries retinol released by the liver

What are the functions of vitamin A

Vision

Maintaining healthy cells

Fighting infections and bolstering immune function

Promoting growth and development

Describe how vitamin A effcts vision

Changes incoming light to visual images

Keeps eye’s surface healthy

Allows night and color vision (rhodopsin and iodopsin)

Describe how vitamin A effects cell differentiation

Vitamin A required to turn on cell differentiation of stem cells

Describe how Vitamin A effects immunity

Needed to replace epithelial cells, which are vital to the immune system

Needed to produce immune cells

Describe how vitamin A effects reproduciton

In men, supports sperm production

In women, maintains fertility

Describe how vitamin A effects bones

Needed for both bone growth and remodeling

Lack of vitamin A during childhood can lead to weak, poorly formed bones

Excess can break down bone

What is RAE

Retinol activity equivalent (RAE) created to develop dietary recommendations

What is the RDA of Vitamin A for men

900 µg RAE

What is the RDA of vitamin A for women

700 µg RAE

What are some food sources of Vitamin A

Animal food sources (Retinoids): Liver, dairy, egg yolks

Fortified foods

Plant food sources (Provitamin A carotenoids): Dark green and yellow-orange veggies

Describe Vitamin A deficiency

Rare in North America and Western Europe

Leading cause of child-blindness worldwide

Who is at risk for Vitamin A deficiency

Newborns

The impoverished

People with alcoholism or liver disease

fat malabsorption syndromes

How does vitamin A deficiency effect the eyes

Night blindness and Xerophthalmia

How does Vitamin A deficiency effect the skin and other epithelial cells

hyperkeratosis

How does a Vitamin A deficiency effect immune function

Vulnerable to infection

Describe vitamin A toxicity

Excess preformed vitamin A is a known teratogen

Retinol can cause spontaneous abortions

Acne treatment: Retinoic acid is commonly prescribed to treat acne and can contribute to Vitamin A toxicity.

What are the Carotenoids of Vitamin A

Alpha-carotene, Beta-carotene (most common), Lutein, Zeaxanthin, Cryptoxanthin, Lycopene

What are the functions of Carotenoids

No technically essential

Can be potent antioxidants

Bolster immune function

Protect vision

Lower risk of certain cancers

Describe the absorption and storage of carotenoids

Body absorbs 20-40% of carotenoids eaten

Proportion drops as you consume more

Dietary fat, protein, and vitamin E enhance absorption

Liver and Adipose tissue are primary storage locations

What are some sources of carotenoids

Orange and yellow fruit/veggies, dark green veggies

Chopping and cooking helps release carotenoids makes them easier to absorb

Describe Carotenoid supplementation

Can cause more harm than good

Should not be taken without careful consideration by a healthcare provider

No UL set

Not recommended for general population

Describe Vitamin D

Synthesized and functions like a hormone

Not always necessary in the diet, body makes plenty with exposure to the sun

Essential for bone health

protects against certain cancers and other chronic diseases

Describe the forms and foundations of Vitamin D

Can be considered a vitamin or a hormone. It is created in one part of the body, and regulates activities in other parts like a hormone

When UV rays from the sun strike the skin, they convert a precursor in the body into vitamin D

Ten compounds exhibit antirachitic properties (D2 and D3)

What are the functions of Vitamin D

Regulation of blood calcium levels

Regulation of cell differentiation and growth

Prevention of cancer cell division

Anti-inflammatory proterties

Regulation of insulin formation and secretion

Describe how vitamin D regulates blood calcium levels

Parathyroid hormone and calcitonin balance calcium in bone, excreted from kidneys, absorbed in the small intestine

Describe the dietary recommendations for Vitamin D

DRI assumes minimal sunlight exposure

Caution against exceeding recommendations

Infants, children, and adolescents consume a minimum of 400 IU of daily vitamin D

Ages 1-70= 600 IU per day

Older than 70 is 800 IH per day

What are some sources of Vitamin D

Sunlight

Few food contain Vit D naturally: oily fish, cod liver oil

Fortified foods:Milk, cereal, orange juice

Supplements

Describe Vitamin D deficiency

High prevalence worldwide

Rickets in children: Bones weaken and skeleton fails to harden

Describe osteomalacia

Soft bones, increases risk for fractures

Describe osteoporosis

Porous bones, declining bone density and strength

Describe who other risks for vitamin D deficiency

Cancers, type 1 diabetes, multiple sclerosis, rheumatoid arthritis, hypertension

Infants, older adults, and high BMI individuals are at risk

Describe Vitamin D Toxicity

Severe, but unlikely

Sun exposure does not cause toxicity

High supplement doses can be toxic

Describe Vitamin E

Many benefits not supported by science.

May be a protector against aging

What are the forms of Vitamin E

Only alpha-tocopherol considered for human Vitamin E requirement

• GI tract absorbs 20-80%

Stored mainly in adipose tissue

• Does not accumulate in the liver

Describe the functions of Vitamin E

It is an antioxidant

• Protects cell membranes from free radical damage

• May lower risk of some chronic diseases such as ♡ disease

• Evidence does not support large-scale supplementation

Describe the dietary recommendations of Vitamin E

Related to body size and intake of polyunsaturated fatty acids

RDA says 15 mg/day for adults; 19 mg/day if breastfeeding

What are some sources of Vitamin E

Nuts, seeds, vegetable oil, whole grain, germ oil, fruits/veggies, animal products

20% comes from salad oils, margarine, and shortening

Cooking, processing, and storage can reduce vitamin E content

Describe vitamin E Deficiency

Rare in North America

occurs with fat malabroption or rare genetic disorders

Features premature hemolysis

Describe vitamin E toxicity

Nontoxic; adverse effects have not been found

Large doses can interfere with blood clotting

What are the functions of Vitamin K

Promotes blood clotting

Assists bone formation

Evidence does not support supplementation

Describe Vitamin K dietary recommendations

Vary by age

typical diets easily meet recommendations for blood clotting

Men: 120 mg/day

Women: 90 mg/day

Describe the food sources of Vitamin K

Green leafy veggies

Vegetable oils: may not be a reliable source

Limited in animal foods

Describe the intestinal bacteria sources of Vitamin K

Vitamin K produced by bacteria absorbed in the colon

Describe Vitamin K deficiency

Rare in healthy adults

tested prior to surgery

Megadoses of Vitamin A and E counteract K

Large fluctuations can interfere with anticoagulant therapy

Newborn babies at risk

Describe the 8 B-vitamins and Vitamin C

Body does not store water-soluble vitamins in appropriate amounts (exception of B12)

More fragile than fat-soluble vitamins

What are the best methods for water-soluble vitamins

steaming, stir-frying, and. microwavin

What are the functions of Thiamin

Coenzyme in energy metabolism

Helop break down glucose, make RNA and DNA; helps power protein synthesis

Helps synthesize and regulate NT’s

What are the dietary recommendations for thiamin

Men: 1.2 mg

Women: 1.1 mg

Pregnancy and lactation increase requirments

What are the food sources of thiamin

pork, legumes, nuts and seeds, fish and seafood

Enriched grain products

Define Beriberi

A thiamin deficiency

Overall profound muscle weakness and nerve destruction

Define Wernicke-Korsakoff syndrome

Thiamin deficiency

Alcohol-induces, with mental confusion, staggering, and constant eye movements

Describe Thiamin toxicity

No UL for this nutrient

Kidneys rapidly excrete excess

Describe the functions of Riboflavin

Accepts and donates electrons easily

• Participates in many oxidation-reduction reactions

Coenzyme in energy metabolism

Supports antioxidants

Describe the dietary recommendations for riboflavin

Men: 1.3 mg

Women: 1.1 mg

Pregnancy and lactation increase needs

What are some sources of riboflavin

Most plant and animal foods

Milk/yogurt products

bread products

Enriched grains, organ meats

almonds, mushrooms, cottage cheese

Describe riboflavin deficiency

rare

Signs include glossitis, angular stomatitis, cheilosis, and seborrheic dermatitis

Then characteristic anemia develops

Usually coexists with other nutrient deficiencies

Describe riboflavin toxicity

No reported cases

No UL set

Describe the functions of Niacin

Coenzyme in energy metabolism

• powers conversion of pyruvate to lactate in anaerobic conditions

Supports fatty acid synthesis

What are the dietary recommendations for niacin

Body can make it from tryptophan

Men: 16 mg

Women 14 mg

Pregnancy and lactation increase need

What are the sources for niacin

Whole and enriched grains

Meat, poultry, fish, nuts, and peanuts

Describe niacin deficiency

Pellagra (mal de la rosa)

• redness at the neck and rough skin

• “four D’s”: dermatitis, diarrhea, dementia, and death

Describe niacin toxicity and medicinal uses

Ul is 35 mg

Side effects: skin flushing, liver damage

Sometimes used to treat high blood cholesterol

What are the functions of pantothenic acid

needed for glucose metabolism

building block of fatty acids

What are the Dietary recommendations for pantothenic acid

Little data is available

AI is 5 mg for adults

What are the sources of pantothenic acid

Widespread in foods

Meat, mushrooms, potatoes, oats, tomato products, yeast, egg yolk, broccoli, whole grains

Easily damaged by freezing, canning, and refining

Processing can reduce content by 75%

Describe Pantothenic Acid deficiency and toxicity

Rare

UL has not been established

Describe biotin functions

Coenzyme in dozens of reactions

• amino acid metabolism

• fatty acid synthesis

• release of energy from fatty acids

• DNA synthesis

Biotin-containing enzymes mainly catalyze carboxylation reactions

Describe the dietary recommendations for biotin

Insufficient data

AI is 30 mcg/day for adults

What are the sources for biotin

Liver, cooked eggs, nuts, seeds

Protein avidin (raw egg whites) binds biotin and prevents absorption

Describe biotin deficiency and toxicity

rare

UL has not been established

What are the functions of vitamin B6

Coenzyme that supports protein metabolism, blood cell synthesis, carbohydrate metabolism, NT synthesis

Primarily helps metabolize amino acids and other nitrogen-containing compounds

Helps the body make the 11 nonessential amino acids

What are the dietary recommendations for B6

Adults: 1.3 mg

More for older adults

higher in pregnancy and lactation

What are the sources of B6

Fortified, ready-to-eat cereals

Mixed foods containing meat, fish, or poultry

Starchy veggies and non-citrus fruits

Especially sensitive to temp

Describe Vitamin B6 deficiency

rare

Anemia, seborrheic dermatitis, neurological systems

Disrupts homocysteine metabolism, leading to increased blood levels of homocysteine

Describe toxicity and medicinal use of vitamin B6

can cause irreversible nerve damage and GI symptoms

UL is 100 mg/day for adults

What are the functions of folate

Coenzyme for DNA synthesis and cell division

Needed for normal RBC synthesis

Reduces neural tube defects

What are the dietary recommendations for folate

Absorbed more readily from supplements and fortified foods

At least 400 mcg DFE (dietary folate equivalents) per day

• Increases significantly during pregnancy

What are the sources of folate

Fortified cereals

Enriched grains and flour

Green leafy veggies, oJ, sunflower seeds, legumes

Extremely vulnerable to heat and light

Describe folate deficiency

10% of U.S population may have insufficient folate stores

Anemia

neural tube defects: Can prevent spina bifida and anencephaly

Diet high in folate may help prevent cancers and ♡ disease

Describe folate toxicity

Can make Vitamin B12 deficiency

• older adults at increased risk

Hypersensitive people may suffer hives or respiratory distress

UL is 1000 mcg per day

Describe the functions of B12

Needed for normal folate function

• DNA and RBC synthesis

• Metabolize homocysteine

Maintenance myelin sheath around nerves

Describe vitamin B12 absorption

Complex process

Requires adequate stomach acid and intrinsic factor

Body stores it in large amounts