nutrition chapter 8
vitamin A defiency
certain epithelial cells produce too much keratin, protein found in hair, nails, out-layers of skin,
B-6 medicine
claims help with PMS, nerve damage, walking difficulties, numbness hands and feet
Riboflavin (B2)
coenzyme for metabolism of carbohydrate, lipids, and amino acids Dairy foods, liver, and enriched grains are major food sources
food-cobalamin malabsorption
common in older adults due to declining gastric production. Also can occur:• In people with • After gastric bypass surgeries• When taking certain medications (e.g., stomach acid reducers)
vitamin
complex organic compund that the body can't make enough of, naturally occurs in common foods, defieicnecy condition occurs when viatmin is missing in diet, good health is restored id defiecny disorder is trated early by supplying missing nutrient
fat soluble are absorbed with
dietary fat, some fat is needed in the body,
vitamin C medicine
does not prevent common cold, may reduce sevrity, reduces oxidation of LDL, eating more fruits and vegetables reduced risk of cancer
taking vitamins ____ replace the need to eat a healthy diet
does not, wide variety from
vitamins ------- energy
don't supply, but may participated in chemical reactions
xeropthalmia
dry eyes, untreated leads to blind
neural tube defect
during the first few weeks after conception, the neural tube forms.- Neural tube develops into the brain and spinal cord. • Folate-deficient pregnant women are at risk of giving birth to infants with neural tube defects.
carcinogens
environmental agents that are cancer
folate (b-8)
folic acid (synthetic) and folate (natural) functions: -part of coenzyme tertrahydrofolic acid DNA and amino acid metabolism Good Food Sources of Folate - Leafy green vegetables , liver, legumes asparagus, broccoli, and oranges
in the united states, severe defiencies are uncommon because
food preservation practices, food enrichments and fortification, availably of fruits and vegetables
vitamin k examples
kale, spinach, broccoli, green vegetables
Early deficiency
lack of folate affects cells such as red blood cells that rapidly divide, can't divide,
two main factors that influence vitamin retention in products are
length of time since harvest, storage conditions since harvest
reducing the risk
limit alcohol, healthy weight, active, healthy food,
Vitamin A toxicity
liver damage, excess beta-carotene, yellowing of the skin, generally harmless, may occur in infants
b-6 and b-12
lowers homocysteine levels when taken together CVD- suggest does not reduce change of heart attack alhezimers diseases no evidence
synthetic
made in laboratories by chemist, nautral and equal activity have equal activity except: naturalv vitamin
cancerous
malignant cells are "out of control" and can spread a mass of cancerous s=cells results in tumor
Vitamin K deficiencies
may occur in newborns or people with impaired liver function or absorption on long term antibiotic therapy
vitamin D
metabolize calcium and phophourus, production and maintencacne of healthy bones
water soluble vitamins are
most functions as compomenents of specific coenzymes many enzymes require coenzymes to function
Vitamin E deficiency
nerve dmage, imparied immune sytsem, blindness
vitamin as medicine
niacin as medicine Uses: - High doses can lower LDL cholesterol and raise HDL cholesterol 2• Side effects:- flushing on face and chest, itchy skin, GI tract upset, and liver damage- megadoses are very toxic, so a qualified medical practitioner (e.g., physician) should be consulted before using
vitamin k toxicity
none natural, synthetic forms are toxic
function (vitamin C)
not part of a coenzyme but needed for: collagen synthesis, protein that gives stregth to connective tissues antioxidant activity major roles: immune system functioning Synthesis of bile, certain neurotransmitters and hormones
thiamin (B-1)
part of coenzyme involved in release of energy from carbs metabolism of certain amino acids synthesis of neurotransmitters
beta-carotene
plant sources vitamin a, yellow, red, orange, green fruits, vegetables, one of a few catonetiods (plant pigments)
natural sources
plants, animals, fungi, bacteria
defiencies result from
poor diets or certian health conditions
vitamin enrichment and fortification
raw foods can lose nutrients during processing whcih includes refinement
parathyroid hormone
released when blood ca levels drop stimulates kidney
Vitamin D defiency
rickets, uncommon in US, alot of people don't get enough viatimin D, too much toxic
most absorption occurs
small intestine, absorption is not 100% efficient, absorption increases when more of the vitamin is needed ex: growth, pregnancy, lactation
coenzymes
small molecules that regulate chemical reactions by interacting with enzymes
many medical researchers ______________ excess oxidation is responsible for promoting chemical changes in cells that lead to
suspect; cancer, stroke, heart attack, alzheimers disease, premature aging
night blindness
the inability to see in dim light, early sign fo vitamin A deficiency, rods and cones need vitamin A to function properly
beriberi
thiamin deficiency; people have weak, poor muscular coornidations my develop cardiovascular problems and edema
Wernicke-Korsakoff syndrome
typically seen in alcoholics because alcohol decreases absorption and increases excretion
major functions
vision and reproductions, cellular, immune, eptitheial cell production and maintenance
most susceptible to loss
vitamin C, thiamin, folate are easily destroyed by improper storage
retinol
Vitamin A
rickets
Vitamin D deficiency in children soft bones
oxidations reactions
can form radicals or free radicals, substances with an unpaired electron loss of electrons
Vitamin E as medicine
cardiovascular disease, cancer, Alzheimer's, not true
anencephaly
brain does not form properly
Vitamins differ from carbohydrates, proteins, and fats because they __________.
both organic, no calories, micronutrients, small amounts
major risk factors
-age -family history -environmental -tabacco -radiation -bacterial/ viral -hormones -alcohol -foods
comparing amounts of nutrients in a food
1 oz of bread --- 0.0005% vitamins
people who live south of the
33rd parellel and are outdoors when sunlight is most intense are mostly likely synthesizing adequate prohormones D
cancer
A group of chronic diseases characterized by cells that have mutated (have damaged genes).
intrinsic factor
A substance produced by the mucosa of the stomach and intestines that is essential for the absorption of vitamin B12.
antioxidant
A substance that gives up electrons to stabilize free radicals
Fat souble vitamins include.
A, D, E, K, don't dissolve in water or urine, stored in the body may be toxic, associated with lipids in foods and the body
dietary supplements
AMD (adult macular degneration) is one of the leading causes of blindness among older adults in U.S.• Risk factors for AMD are ____________, __________, and advanced age, but diet also plays a role.• AMD is associated with changes in the macula.• The macula contains the carotenoids lutein and zeaxanthin. • In the AREDS Study, patients with AMD took high amounts of vitamins C and E, beta-carotene, and the minerals copper and zinc.• This combination slowed the progression• of AMD.• There was no clear scientific evidencethat taking antioxidant supplements prevents healthy people from developing AMD.
water soluble vitamins
B and C (the rest of vitamins), dissolve in watery componets of foods and the body, excreted in urine, non toxic,. choline is generally referred to as vitamin like
carotenoids as medicine
Diets rich in fruits and vegetables are associated with lower risk of certain cancers, CVD, and age- related macular degeneration ( AMD ). • Dietary supplements containing beta-carotene fail to show benefits for cancer and AMD risks. • Lutein and zeaxanthin (carotenoids) may help slow progression of AMD. Dietary supplements with beta-carotene may be harmful, especially among smokers. Reasonable advice:
vitamin B-6
Functions- Part of coenzyme needed for amino acid metabolism deficiency- rarely occurs but signs and symptoms • Dermatitis, anemia, convulsions, depression, and confusion •Toxic -(megadoes)
Niacin (B-3)
Functions- Part of two coenzymes that participate in at least 200 reactions deficiency- 4 D's -dermatitis -diarrhea -dementia -death toxic amounts- can cause GI ulcers, vision loss, and liver damage
diseases that affect the ____________ can reduce vitamin absorption
GI traact
choline
Humans require choline, especially during prenatal (before birth) development.Choline is considered to be a vitamin- like nutrient.The body can make choline, but under certain conditions, the body does not synthesize enough to meet its needs.
spina bifida
Spine does not form properly before birth and fails to enclose the spinal cord.
absorption of dietary B-12
bound to proteins, after released from protein, B-12 must bind to intrinsic factor for absorption
fortification
addition of an nutrient to a wide array of commonly eaten processed foods during their manufacturing
grain enrichement
addition of specific amounts of thiamin, riboflavin, niacin, flocic, acid and the mineral iron, does not restore all nutrients grain loses during refining
osteomalcia
adult rickets
at risk for vitamin defiency
alcoholics, older adults, hospitalized, anorexia nervosa, GI disorders, rare metabolic conditions
vitamin E
antioxidant found in cells, protects polyunsaturated fatty acids, mains immune system function sunflower seeds
vitamin B-12 functions
art of coenzymes needed for: • folate metabolism • Maintenance of myelin shealth
vitamin k
assists in blood clotting
maximize vitamins
avoid buying wilted, bruised, or shriveled produce, store near freezing temps, air tight conditions, high humidity, cook in small amounts of water, avoid cutting foods in tiny pieces, quick cooking methods, freeze produce
b vitamins order
b-1 b-2- riboflavin b-3- Niacin
unlikely vitamins need to still be discovered
babies grow and thrive on formula and feeding tubes owuldn't be able to survive
free radical generating substances
fried foods, smoking, alcohol, pesticides
beta- carotine and vitamins E and C
function as antioxidants
reduction
gain of electrons
pernicious anemia
genetic defect reduces production of intrinsic factor • Megaloblastic anemia• Nerve damage• Confusion• Difficulty walking and maintaining balance• Death
antioxidants work
giving up an electron to free a radical, protects other molecules, action stabilizes the free radical
vitamins may
have hormonal like action participate in certain chemical reactions -regulate certain body processes -cell division and development -growth and maintain tissues
free radical
highly reactive substances because they have an unpaired electron can remove an electron from amore stable molecule such as dna protein polyunsaturated fatty acid
vitamin c toxicity
increase risk of kidney stone, defiencity scurvy- loss teeth, gums, poor wound healing, bruises, depression
toxicity of E
interfere w vitamin K, role in blood clotting
cystic fibrosis
interferes with fat digestion and fat soluble vitamin absorption, may need to take supplemental sources of vitamins