Lesson 9 Water-Soluble Vitamins Chapters 10
Who should not take supplements?
- Men and postmenopausal women should not take iron supplements -Smokers should not take beta-carotene supplements - postmenopausal women should not take vitamin A supplements -Surgery patients should not take vitamin E supplements during the week before surgery
What is required for supplements when sold?
- Nutrition labeling for dietary supplements is required. -Labels may make nutrient claims (as "high" or "low") according to specific criteria (for example, "an excellent source of vitamin C"). -Labels may claim that the lack of a nutrient can cause a deficiency disease, but if they do, they must also include the prevalence of that deficiency disease in the United States. -Labels may make health claims that are supported by significant scientific agreement and are not brand specific (for example, "folate protects against neural tube defects"). -Labels may claim to diagnose, treat, cure, or relieve common complaints such as menstrual cramps or memory loss, but may not make claims about specific diseases (except as noted previously). - Labels may make structure-function claims about the role a nutrient plays in the body, how the nutrient performs its function, and how consuming the nutrient is associated with general well-being. - The manufacturer is responsible for ensuring that the claims are truthful and not misleading. Claims must be accompanied by an FDA disclaimer statement: "This statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease."
Other nonvitamins include:
- PABA (para-aminobenzoic acid) -bioflavonoids (vitamin P or hesperidin) -pyrroloquinoline quinone (methoxatin) - orotic acid -lipoic acid, - ubiquinone (coenzyme Q10) -"vitamin O" (oxygenated saltwater) - "vitamin B5 " (another name for pantothenic acid), - "vitamin " (also called "pangamic acid," a hoax), - "vitamin " (laetrile, an alleged "cancer cure"
Why is PLP (pyridoxal phosphate) valuable in protein and urea metabolism?
Because it has the ability to remove amino groups
The amount of a vitamin absorbed from food that can be used by the body
Bioavailability
Category of vitamin that requires bile for absorption
Fat-soluble
Required for DNA synthesis and break down of the amino acid homocysteine
Folate
What does Vitamin B12 depend on for activation?
Folate
Neurotube Defects Disease
Folate Deficiency
What is folate vulnerable to?
GI tract injuries
Intrinsic Factor
Glycoprotein secreted in the stomach that binds to vitamin B12 for absorption
Antioxidant vitamins that reduce oxidation of LDL blood cholesterol decrease risk for this disease
Heart Disease
Where are water-soluble vitamins found in foods?
In the watery compartments of foods
What causes hemorrhaging with a vitamin C deficiency?
Inadequate collagen synthesis
One of the differences between protein, carbohydrate and fat and vitamins
Individual unit structure
Where was beriberi first observed?
Indonesia; when a custom of polishing rice became widespread
If the GI tract cells are damaged, ehat happens to folate?
It is lost
What allows vitamin C to perform as an antioxifant?
It loses electrons easily
How long does it take for a vitamin B12 deficiency?
It may take several years for people who stop eating animal-derived foods to develop deficiency symptoms because the body recycles much of its vitamin , reabsorbing it over and over again and conserving its supply.
What happens to FDA during energy metabolism?
It picks up 2 hydrogens (with their electrons) from the TCA cycle and delivers them to the electron transport chain
What is the thiamin RDA primarily based on?
Its role in enzyme activity
Newborns routinely receive a single dose of vitamin______ at birth to prevent abnormal bleeding
K
What is a deficiency symptom of choline?
Liver damage
How do researchers determine the bioavailability of a vitamin
Looking at many factors: Efficiency of digestion and time of transit through the GI tract Previous nutrient intake and nutrition status Method of food preparation (raw, cooked, or processed) Source of the nutrient (synthetic, fortified, or naturally occurring) Other foods consumed at the same time
Pernicious Anemia
Macrocytic anemia that reflects a vitamin B12 or folate deficiency
Neural Tube Defects
Malformation of the spinal chord, brain or both during embryonic development that can often result in lifelong disability or death
What types of foods contain niacin?
Meat, poultry, fish, legumes, and enriched and whole grains (this contributes to about half the niacin people consume)
What food can vitamin B6 be found?
Meats, fish, poultry, potatoes and other starchy vegetables, legumes, noncitrus fruits, fortified cereals, liver, soy products
What is the RDA of thiamin for men and women?
Men: 1.2 mg/day Women: 1.1 mg/dat
What is the RDA of riboflavin?
Men: 1.3 mg/day Women: 1.1 mg/day
What is the RDA of niacin for men and women?
Men: 16 mg NE (niacin equivalents)/day Women: 14 mg NE/day
What is the AI for choline?
Men: 550 mg/day Women: 425 mg/day
Vitamins fall into this category of nutrients
Micronutrients
Coenzymes
Molecules that work with enzymes to facilitate the enzyme's activity
What are the two coenzymes forms of niacin?
NAD (nicotinamide adenine dinucleotide) NADP (the phosphate form)
In a food containing 1 milligram of niacin and 60 milligrams of tryptophan, what is the equivalence of niacin and niacin equivilance?
Niacin = 2 milligrams Niacin equivalents = 2
Pellagra Disease
Niacin Deficiency
Pellagra
Niacin deficiency disease characterized by the four Ds - diarrhea, dermatitis, dementia and death
Do biotin deficiencies occur often?
No
Do large doses of vitamin B6 enhance muscle strength or physical endurance?
No
Do the receptors recognize B12 without intrinsic factor?
No
Does cooking destroy riboflavin?
No
Does nicotinamide produce niacin rush?
No
Does vitamin B12 have an UL?
No
Is biotin needed in large amounts?
No
Are manufacturers of organic or natural vitamins boast that their pills are purified from real foods rather than synthesized in a laboratory more effective?
No and they often cost more
Does consuming 10 milligrams of vitamin C daily saturate all the body tissues?
No higher intakes will increase the body's total vitamin C
Has a UL been determined for thiamin?
No, and no adverse effects have been associated with excess
Has an UL been established for pantothenic acid?
No, and no toxic effects have been reported
Does corn provide niacin?
No, at least 70% of the niacin in corn is bound to complex carbs and small peptides, making it unavailable for absorption
Has a UL been set for biotin?
No, because no adverse effects have been reported
Are fat soluble vitamins excreted?
No, they tend to remain in fat-storage sites in the body rather than being excreted
How are riboflavin and vitamin B6 interdependent?
One of the riboflavin coenzymes, FMN, assists the enzyme that converts vitamin B6 to its coenzyme form PLP. Consequently, a severe riboflavin deficiency can impair vitamin B6 activity.
When does the body make niacin from tryptophan?
Only after protein synthesis needs have been met
Term that describes the carbon-hydrogen bonds in vitamins
Organic
Vitamins
Organic, essential nutrients required in small amounts by the body for health
Condition in which unstable molecules and oxidants exceed the body's ability to handle them and prevent damage
Oxidative stress
What is the inactive form of a vitamin called?
Precusor
Retinoids
Proper name vitamin A that includes the biologically active forms - retinol, retinal and retinoic acid
Milk and milk products are the greatest contributors of this vitamin our diets
Riboflavin
What are the symptoms of vitamin B6 deficiency?
Scaly dermatitis; microcytic anemia; depression, confusion, convulsions
What are some symptoms of riboflavin deficiency?
Sore throat; cracks and redness at corners of mouth (cheilosis); painful, smooth, purplish red tongue (glossitis); inflammation characterized by skin lesions covered with greasy scales
How do vitamins differ from proteins, carbs, and fats?
Structure function food contents
Antioxidant
Substances that stabilize free radicals to prevent celllular and DNA damage
If folate is trapped, what can the body not do?
Support DNA synthesis and cell growth
What is folate's primary coenzyme?
THF (tetrahydrofolate)
What contradicted commonly help medical opinions that diseases were caused only by infectious agents?
That a disease such as pellagra could be caused by diet inadequacies—and not by pathogens
Details of supplement regulation are defined in the Dietary Supplement Health and Education Act of 1994, which was intended to enable consumers to make informed choices about dietary supplements.
The act subjects supplements to the same general labeling requirements that apply to foods.
Dietary Folate Equivalents
The amount of folate available from naturally occurring sources, fortification, and supplements
Niacin Equivalents
The amount of niacin present in food, including the amount that can theoretically be made from tryptophan in the food
How is the food content of a vitamin different from proteins, carbs, and fats?
The amounts required daily are measured in micrograms, or milligrams; not grams
With researched information, that is the Estimated Average Requirement (EAR) calculated to estimate?
The average amount that appears sufficient for half of the population
What do asprin and antacids interfere with?
The body's folate status; aspirin inhibits the action of folate-requiring enzymes, and antacids limit the absorption of folate.
What is pantothenic acid part of?
The chemical structure of coenzyme A (the same coenzyme that forms acetyl CoA)
What is thiamin the vitamin part of?
The coenzyme TPP (thiamin pyrophosphate)
What does the thiamin pyrophosphate (TPP) coenzyme participate in?
The conversion of pyruvate to acetyl CoA
What does the Tolerable Upper Intake Level (UL) set for vitamins?
The highest amount that appears safe for regular consumption
Alpha-Tocopherol
The only member of the family of compounds known as vitamin E that is biologically active
The amount of vitamin form foods depends on what?
The quantity provided and the vitamin's bioavailability
Bioavailability
The rate and the extent to which a nutrient is absorbed and used by the body
What depends on both folate and vitamin B12?
The regeneration of the amino acid methionine and the synthesis of DNA and RNA
What path does folate take?
The same enterohepatic circulation as bile
What is a way to evaluate foods?
Their nutrient contributions of their nutrient density
Why are vitamins sometimes described as micronutrients?
They are are measured in micrograms, or milligrams; not grams
When fat soluble vitamins reach the cells, what do they do?
They are held in fatty tissues and the liver until needed
What happens when nutrients are taken in pure concentrated form?
They are likely to interfere with one another's absorption or with the absorption of nutrients in foods eaten at the same time
How is the function of a vitamin different from proteins, carbs, and fats?
They do not yield energy when metabolized; but many do assist the enzymes that help to release energy from carbohydrates, fats and proteins
What happens if the body has a large excess of vitamins?
They may overwhelm the system. creating adverse effects
The richest source for this vitamin is pork
Thiamin
What are the B vitamins?
Thiamin Riboflavin Niacin Biotin Pantothenic Acid Vitamin B6 Folate Vitamin B12 Choline
Beriberi Disease
Thiamin deficiency
Beriberi
Thiamine deficiency disease characterized by muscle weakness, edema or both
The bioavailability of a vitamin in food refers to the amount that is absorbed and can be used by the body True False
True
Vitamins differ from protein, carbohydrate and fat in that they are individual units that don't require digestion. True False
True
Free Radicals
Unstable molecule with one or more unpaired electron
The body can convert the precursor beta-carotene in food to the active form of this vitamin
Vitamin A
Vitamin that promotes vision
Vitamin A
Night Blindness disease
Vitamin A deficiency
Beta-Carotene
Vitamin A precursor that is part of the family of carotenoids found in food
Pernicious Anemia disease
Vitamin B 12 deficiency
Required for folate activation and maintenance of myelin sheaths surrounding nerves
Vitamin B12
This vitamin is found only in foods of animal origin
Vitamin B12
What vitamin is closely related to folate?
Vitamin B12
Citrus is often thought of as the main source for this vitamin, but many fruits and vegetables are rich sources
Vitamin C
Primary antioxidant in blood and cofactor in collagen production
Vitamin C
Scurvy disease
Vitamin C deficiency
Scurvy
Vitamin C deficiency disease
Increases mineral absorption in the GI tract and acts as a hormone to maintain serum calcium levels
Vitamin D
Often called the "sunshine vitamin", this vitamin is also found in fatty fish
Vitamin D
Rickets disease
Vitamin D deficiency
Rickets
Vitamin D deficiency disease that affects children
Hemolytic Anemia disease
Vitamin E deficiency
Known as the "blood-clotting" vitamin
Vitamin K
Vitamin K
Vitamin that is responsible for activating proteins that clot blood
Fat-Soluble Vitamins
Vitamins that are insoluble in water and require a protein carrier for transport in blood
Water-Soluble Vitamins
Vitamins that are soluble in water and in blood
Category of vitamin that is absorbed directly into the bloodstream
Water-soluble
What are the two basic questions to answer when deciding to take a vitamin-mineral supplement?
What form do you want? What vitamins and minerals do you need?
When must bioavailability differences be considered?
When establishing folate recommendations
When do scurvy symptom start to appear from a lack of vitamin C in the diet?
When vitamin C concentrations fall to about a fifth of optimal levels (this may take more than a month on a diet lacking vitamin C)
As each vitamin was discovered, how was it named?
With a name, and sometimes a letter and a number
Can folate be reabsorbed repeatedly?
Yes
Do many vitamins have multiple names?
Yes
Does naturally occurring niacin from foods have a physiological effect that causes no harm?
Yes
Does the average niacin intake exceed recommendations in the US?
Yes
Is pantothenic acid deficiency rare?
Yes
Does niacin leach to water when cooking?
Yes, but it can withstand reasonable cooking times
Can GI tract bacteria synthesize some water soluble vitamins?
Yes, but not in great enough quantities to meet the bodys needs
Are free radicals ever helpful?
Yes, when activated by the immune system They act as ammunition in an "oxidative burst" that demolishes the offending viruses and bacteria and destroys the damaged cell
What is pantothenic acid?
a B vitamin. The principal active form is part of coenzyme A, called "CoA" throughout
What does riboflavin serve as?
a coenzyme in many reactions; most notable in energy metabolism
Antagonist
a competing factor that counteracts the action of another factor. When a drug displaces a vitamin from its site of action, the drug renders the vitamin ineffective and thus acts as a vitamin antagonist.
What do immune system cells use when called into action?
a great deal of oxygen and produce free radicals
Why does inadequate intake of vitamin B12 occur?
a lack of hydrochloric acid or a lack of intrinsic factor. Without hydrochloric acid, the vitamin is not released from the dietary proteins and so is not available for binding with the intrinsic factor. Without the intrinsic factor, the vitamin cannot be absorbed.
What is pernicious anemia?
a macrocytic anemia that reflects a vitamin B12 deficiency caused by lack of intrinsic factor and characterized by abnormally large and immature red blood cells. Other symptoms include muscle weakness and irreversible neurological damage.
Nonotechnology
a manufacturing technology that manipulates atoms to change the structure of matter.
What does the monoglutamate of a folate attach to?
a methyl group (CH3), which inactivates folate for storage
What is carnitine?
a nonessential nonprotein amino acid made in the body from lysine that helps transport fatty acids across the mitochondrial membrane. As a supplement, carnitine supposedly "burns" fat and spares glycogen during endurance events, but in reality it does neither.
What is inositol?
a nonessential nutrient that can be made in the body from glucose. Inositol is a part of cell membrane structures.
What happens if there is insufficient evidence to determine an EAR (Estimated Average Requirement ) needed to set an RDA (Recommended Dietary Allowance)?
a recommendation based on the average amount of a nutrient that a group of healthy people consumes (an Adequate Intake (AI)may be used instead of an RDA
What is a cofactor?
a small, inorganic or organic substance that facilitates the action of an enzyme.
Where does thiamin occupy?
a special site on the membranes of nerve cells
What is histamine?
a substance produced by cells of the immune system as part of a local immune reaction to an antigen.
What is niacin flush?
a temporary burning, tingling, and itching sensation that occurs when a person takes a large dose of nicotinic acid; often accompanied by a headache and reddened face, arms, and chest.
What are advanced symptoms of vitamin B6 deficiency?
abnormal brain wave patterns and convulsions
How much could dietary tryptophan meet the need for the daily niacin requirements?
about half of the daily niacin requirements for most people
What does solubility in the food sources of different vitamins affect?
absorption transport storage excretion
What can FMN and FDA do?
accept and donate 2 hydrogens
What organ contains the most vitamin c?
adrenal glands
What impairs thiamin absorption and enhances thiamin excretion in urine?
alcohol
What contributes to the destruction and loss of vitamin B6?
alcohol; because it produces acetaldehyde and when that is accumulated, it dislodges the PLP coenzyme from its enzymes and breaks down and is excreted
What has been established by the DRI committee for choline?
an AI
What are the requirements of vitamin c for those who smoke?
an additional 35 milligrams; nonsmokers regularly exposed to cigarette smoke should also be sure to meet their RDA for vitamin C
What does THF (tetrahydrofolate) serve as a part of?
an enzyme complex that transfers 1-carbon compounds that arise during metabolism
How do researchers determine the quantity of a vitamin in a food?
analyze foods to determine the vitamin contents and publish the results in tables such as the USDA Food Composition Database
What are the 2 first dymptoms of a folate deficiency?
anemia and GI tract deterioration
What is one of the most obvious vitamin B12 -deficiency symptoms
anemia commonly seen in folate deficiency characterized by large, immature red blood cells, which indicate slow DNA synthesis and an inability to divide
Vitamins that can donate or take up an electron to neutralize an unstable molecule
antioxidants
Where does vitamin b12 bind with intrinsic factor?
as it passes from the stomach to the small intestine
Why are vitamins in fresh fruits easily destroyed during processing?
because of their organic nature
Why is niacin unique among the B vitamins?
because the body can make it from the amino acid tryptophan
Why is milk sold in cardboard or opaque plastic containers?
because ultraviolet light destroys riboflavin
What food sources have pantothenic acid?
beef, poultry, whole grains, potatoes, tomatoes, broccoli
What can prolonged thiamin deficiency result in?
beriberi
Give an example of a precursor.
beta-carotene, a red-orange pigment found in fruits and vegetables, is a precursor to vitamin A.
What does the liver incorporate excess folate into?
bile
What is important to count when measuring a person's vitamin intake?
both the amount of the active vitamin and the potential amount available from precursors
How can antioxidants neutralize free radicals?
by donating an electron or two to protect other substances from free radical damage
How can a woman consume enough folate?
by eating folate rich foods, folate fortified foods, or a multivitamin daily
How can researcher induce a biotin deficiency?
by feeing raw egg whites, which contains a protein that binds biotin and prevents its absorption
How is scurvy readily resolved?
by increasing vitamin C intake; Moderate doses of 100 milligrams per day are sufficient, curing the scurvy within about 5 days.
How can a person develop niacin rush?
by taking 3 - 4 times more nicotinic acid than the RDA recommends
When do substantial losses of pantothenic acid occur?
by the freezing, canning, and refining processes.
Antioxidant vitamins that protect against cellular DNA damage reduce risk for this disease
cancer
What is folate active in?
cell multiplication
What have inadequate intakes of vitamins and minerals been linked to?
chronic diseases such as heart disease and some cancers and osteoporosis
What is atrophic gastritis?
chronic inflammation of the stomach accompanied by a diminished size and functioning of the mucous membranes and glands. This condition is also characterized by inadequate hydrochloric acid and intrinsic factor—two substances needed for vitamin B12 absorption.
What increases the need for more vitamin C?
cigarette smoking because it contains oxidants, which greedily deplete this potent antioxidant
What else may taking folate before and during pregnancy help to prevent?
congenital heart disease; birth defects, such as cleft lip and cleft palate; and neurodevelopmental disorders, such as autism.
An estimated 4 out of 5 alcohols are thiamin deficient, which does what?
damages the brain's structure and impairs its function
What do antioxidants do in the body?
defecd against free radicals
Both _______ and _____ can be harmful when obtaining vitamins.
deficiencies Toxicities
What are early symptoms of vitamin B6 deficiency?
depression and confusion
What happens if folate is given for a deficiency when it is vitamin B12 that is actually needed?
devastating neurological symptoms
What are the symptoms of pellagra?
diarrea dermatitis dementia eventually death (often called the dour Ds)
An inadequate intake of either riboflavin or vitamin B6 can do what?
diminish the body's niacin supply
Where do water-soluble vitamins move when being absorbed?
directly into the blood
What is beriberi often described as
dry or wet
When does the need for folate rise?
during pregnancy and whenever cells are multiplying
What food sources contain biotin?
egg yolks, liver, soybeans, fish, whole grains; a widespread in foods
What do thiamin and thiamin pyrophosphate (TPP) assist?
energy metabolism
What does vitamin C do in the small intestine?
enhances iron absorption by protecting iron from oxidation
What circulation does vitamin B12 enter?
enterohepatic circulation (like folate)
Where is vitamin B6 stored?
extensively in muscle tissue, unlike any other water soluble vitamin
Which type of vitamin are more likely to reach toxic levels when consumed in excess?
fat soluble
Which vitamins require transport proteins?
fat soluble vitamins
Which vitamins are hydrophobic?
fat-soluble ones are vitamins A, D, E, and K
What sources provide an inaccurate inactive form of vitamin B12?
fermented soy products such as miso (a soybean paste) nor sea algae such as spirulina
What does vitamin C help to form?
fibrous structural protein of connective tissues known as collagen.
What is folate also known as?
folacin or folic acid; pteroylglutamic acid (PGA)
Which vitamin appears to be the most vulnerable to interactions with drugs?
folate
Those with kidney disease, a tendency toward gout, or a genetic abnormality that alters vitamin C's breakdown to its excretion products are prone to what?
forming kidney stones if they take large doses of vitamin C
Molecule with an unpaired or extra electron
free radical
When water soluble vitamins reach the cells, what do they do?
freely circulate in the water filled compartments
What types of foods naturally contiain vitamins?
fresh fruits
In ge whn dones the body best absorb nutrients?
from foods in which the nutrients are diluted and dispersed among other substances that mat facilitate absorption
What effects on the body can taking too much vitamin C produce?
gastrointestinal distress and diarrhea have been reported
What are the symptoms of pantothenic acid deficiency?
general failure of all the body's systems and include fatigue, GI distress, and neurological disturbances
Rice polishing caused what?
germ and bran of the rice grain was their principal source of thiamin. When the germ and bran were removed in the preparation of white rice, beriberi became rampant.
What do the biotin coenzymes also participate in?
gluconeogenesis, fatty acid synthesis, breakdown of certain fatty acids and amino acids
What may folate not reduce the risk of?
heart attacks, strokes, or death from cardiovascular causes.
What can destroy as much as half of the folate in foods?
heat and oxidation during cooking and storage
What does PLP (pyridoxal phosphate) participate in the synthesis of?
heme (the nonprotein portion of the hemoglobin), nucleic acids (such as DNA and RNA), and lecithin (a phospholipid)
What happens if folate is unable to break down homocysteine?
homocystine accumulates, which seems to enhance formation of blood clots and atherosclerotic lesions
What releases vitamin B12 from the proteins that it is attached to in foods in the stomach?
hydrochloric acid and the digestive enzyme pepsin
What are marginal vitamin B 12 deficiency symptoms?
impairment of memory and cognition
When may atrophic gastritis develop?
in response to iron deficiency or infection with Helicobacter pylori, the bacterium implicated in ulcer formation.
When is biotin's role critical?
in the TCA cycle: biotin delivers carbon to 3 carbon pyruvate. This replenishes oxaloacetate (the 4 carbon compound needed to combine with acetyl CoA to keep the TCA cycle turning)
When was the first major report of a vitamin B6 toxicity?
in the early 1980's
What do most vitamin B12 deficiencies reflect?
inadequate absorption, not poor intake
What does lack of riboflavin cause?
inflammation of the membranes of the mouth, skin, eyes, and GI tract.
What are 2 substances have been mistaken for vitamins, but they are not essential nutrients?
inositol (in-OSS-ih-tall) and carnitine
Where is vitamin B12 continuously being secreted?
into bile and delivered to the intestine where it is reabsorbed
What is folate like in supplements?
it is in its monoglutamate form (containing only 1 glutamate)
What does thiamin do when foods are boiled or blanched?
it leaches into water
What is dry beriberi?
it reflects damage to the nervous system and is characterized by weak muscles in the arms and legs
What does the effect of every substance depend on?
its dose
What are the RDA for riboflavin based on?
its role in enzyme activity; most people in the US meet or exceed recommendations
What is anemia of folate deficiency characterized by?
large, immature red blood cells
What foods is folate is especially abundant in?
legumes, fruits, and vegetables
Is niacin vulnerable to losses during food preperation and storage?
less than other water soluble vitamins
What amino acid is corn high in, which interferes with the tryptophan-to-niacin conversion further developing pellagra?
leucine
What is the UL of choline based on?
life-threatening effect of lowering blood pressure
Where is folate stored?
liver and other body cells
What is anemia of folate deficiency known as?
macrocytic or megaloblastic anemia
What does the body use choline for?
make the neurotransmitter acetylcholine and the phospholipid lecithin
What nutrient dense foods contain riboflavin?
many dark green, leafy vegetables (such as broccoli, turnip greens, asparagus, and spinach) appear high on the list.
What does choline do during adulthood?
may improve cognition
What are exceptionally rich in thiamin?
meats in the pork family
The average thiamin intake in the US ______ or _____ recommendations.
meets or exceeds
What role does biotin play in the body?
metabolism as a coenzyme that carries activated carbon dioxide
What are poor folate sources?
milk and meats
What are some of the greatest contributions of riboflavin?
milk and milk products; whole grains or enriched grains are valuable sources as well; nutritional yeast
What food sources contain choline?
milk, eggs, and peanuts and as part of lecithin, a food additive commonly used as an emulsifying agent
What is pantothenic acid involved in?
more than 100 different steps in the synthesis of lipids, neurotransmitters, steroid hormones, and hemoglobin
How much vitamin c is in 1 cup of orange juice?
more than 100 milligrams
What is PLP (pyridoxal phosphate) active in?
more than 100 reactions, including carbohydrate, fatty acid, and amino acid metabolism.
What may prolonged heating destroy?
much of the thiamin in food
What vegetables are among the richest in niacin?
mushrooms, potatoes, and tomatoes
What heavily depends on thiamin?
nerve activity and muscle activity
What do the brain and spine develop from?
neural tube
What does too much vitamin B6 cause?
neurological damage in people who had been taking more than 2 grams of vitamin b6 daily (20 times the current UL of 100 milligrams per day) for 2 months or more.
What does (nicotinamide adenine dinucleotide) NAD protect against?
neurological degeneration
What are advanced symptoms from vitamin B12 deficiency?
neurological symptoms include a creeping paralysis that begins at the extremities and works inward and up the spine
What stresses are known to increase vitamin C needs?
nfections; burns; extremely high or low temperatures; intakes of toxic heavy metals such as lead, mercury, and cadmium; the chronic use of certain medications, including aspirin, barbiturates, and oral contraceptives; and cigarette smoking.
What can the body easily convert nicotinic acid to?
nicotinamide, which is a major form of niacin in the blood
What does an excess of riboflavin cause?
no harm, and no UL has been established.
Is choline a vitamin?
no; it is an essential nutrient that is commonly grouped with the B vitamins
What do NAD (nicotinamide adenine dinucleotide) NADP (the phosphate form) participate in?
numerous metabolic reactions; Central in energy-transfer reactions, especially the metabolism of glucose, fat, and alcohol
Which do vegetables rank higher, a nutrient-per-kcal list or a nutrient-per-serving list?
nutrient-per-kcal list
How much vitamin C is needed to prevent overt symptoms such as scurvy?
only about 10 milligrams daily
What does vitamin c protect tissues from?
oxidative stress of free radicals (prevents disease)
What cancer may folate help to reduce?
pancreatic cancer. Limited evidence suggests that folate may also reduce the risk of esophageal and colorectal cancer.
What was the "burning feet" syndrome that affected prisoners of war in Asia during WWII thought to have been the cause of?
pantothenic acid deficiency
What are the chief functions of pantothenic acid in the body?
part of coenzyme A and used in energy metabolism
What is the niacin-deficiency disease?
pellagra
What do large doses of nicotinic acid from supplements or drugs produce?
pharmacological effects
What do tables of food composition typically list niacin as?
preformed niacin
To correct an overt deficiency disease, a physician may:
prescribe therapeutic doses two to ten times the RDA (or AI) of a nutrient. At such high doses, the supplement is having a pharmacological effect and acting as a drug.
What happens without healthy stomach cells?
production of hydrochloric acid and intrinsic factor diminishes
The conversion of _____ to _____ requires both vitamin C and iron.
proline to hydroxyproline
Antioxidant vitamins that in high doses can stimulate the production of unstable molecules that can cause cellular damage
prooxidant
What does the word synthetic mean?
put together
What are the 3 forms of vitamin B6?
pyridoxal, pyridoxine, and pyridoxamine
What is first to be affected in a vitamin B12 or folate deficiency?
rapidly growing blood cells
What happens when intrinsic factor and vitamin B12 travel to the end of the small intestine?
receptors recognize them and the vitamin is gradually absorbed into the bloodstream and the intrinsic factor is degraded
What is wet Beriberi?
reflects damage to the cardiovascular system and is characterized by dilated blood vessels, which cause the heart to work harder and the kidneys to retain salt and water, resulting in edema
What does vitamin B12 do?
removes a methyl group to activate folate coenzyme
What is NAD (nicotinamide adenine dinucleotide) similar to?
riboflavn coenzymes because it carries hydrogens (and their electrons) during metabolic reactions; including the pathway from the TCA cycle to the electron transport chain
Overdose in vitamins causes:
severe overdoses result in bloody diarrhea, shock, liver damage, coma, and death.
What are the symptoms of biotin deficiency?
skin rash, hair loss, and neurological impairment. Depression, lethargy, hallucinations, numb or tingling sensation in the arms and legs; red, scaly rash around the eyes, nose, and mouth; hair loss
deficiencies of riboflavin, niacin, biotin, and vitamin can all cause what?
skin rashes, but so can deficiency of protein, linoleic acid, or vitamin A
What type of people are the most likely to suffer from a vitamin c deficiency?
smokers
What are the over all vitamin B deficiency symptoms?
smooth tongue or glossitis and skin lesions of cheilosis
What does transport of vitamin B12 depend on?
specific binding proteins
If you choose supplements in pill form, what should you look for?
statements about the disintegration time. The USP suggests that supplements should completely disintegrate within 30 to 45 minutes.
What cooking ways help to conserve thiamin in food?
steaming, and microwaving
How does vitamin C help free radicals during immune fighting activity?
steps in as an antioxidant to control this oxidative activity
nanoceuticals
substances with extremely small particles that have been manufactured by nanotechnology.
What does choline do during pregnancy?
supports the neurological development of the fetus,
What happens without adequate amounts of vitamin B6?
synthesis of key neurotransmitters diminishes, and abnormal compounds produced during tryptophan metabolism accumulate in the brain
Which is given more credit from the DRI committee?
synthetic folate
What do large amounts of vitamin C excreted in the urine obscure the results of?
tests used to detect glucose or ketones in the diagnosis of diabetes
What releases vitamin C and hormones into the blood?
the adrenal glands
What is dietary folate equivalents (DFE)?
the amount of folate available to the body from naturally occurring sources, fortified foods, and supplements, accounting for differences in the bioavailability from each source. μ food folate + (1.7 × μg synthetic folate).
What are niacin equivalents (NE)?
the amount of niacin present in food, including the niacin that can theoretically be made from its precursor, tryptophan, present in the food. 1 NE = 1 mg niacin or 60 mg tryptophan.
What is the RDA for vitamin b6 based on??
the amounts needed to maintain adequate levels of its coenzymes
What may happen to people taking anticlotting medications if they take too much vitamin C?
the anticlotting medications may counteract the effect
What is a pharmacological effect?
the body's response to a large dose of a nutrient (levels commonly available only from supplements) that overwhelms some body system and acts like a drug
What is a physiological effect?
the body's response to a normal dose of nutrient (levels commonly found in foods) that provides a normal blood concentration
What can all three forms of vitamin B6 be converted into?
the coenzyme PLP (pyridoxal phosphate)
What is the neural tube?
the embryonic tissue that forms the brain and spinal cord.
Where do fat-soluble vitamins enter when absorbed?
the lymph then to the blood
What needs to happen for folate to be activated from storgage?
the methyl group must be removed by an enzyme that requires the help of vitamin B12
What does vitamin B12 maintain?
the sheath that surrounds and protects nerve fibers and promotes their normal growth; Bone cell activity and metabolism also depend on VB12
What is beriberi?
the thiamin-deficiency disease characterized by muscle weakness, edema, or both.
What happens after folate coenzyme is activated?
the vitamin B12 coenzyme becomes activated
What do enzymes on the intestinal cells walls do to the polyglutamate of a folate?
they hydrolyze it to monoglutamate and several single glutamates
What part do the kidneys play with vitamins?
they monitor the blood and remove small excesses of water soluble vitamins
What is one of folates key roles in the body?
to break down the amino acid homocysteine
How is PLP (pyridoxal phosphate) used?
to transfer amino groups NH2 from an amino acid to a keto acid, the body can make nonessential amino acids
What does niacin refer to?
two chemical structures: nicotinic acid and nicotin-amide (also known as niacinamide)
What can riboflavin be destroyed by?
ultraviolet rays of the sun or fluorescent light
What is folate like in naturally ocurring foods?
up to 6 glutamates (known as polyglutamate)
Where are fat-soluble vitamins found in foods?
usually together in the fats and oils of foods
Who is most likely to develop a vitamin B12 deficiency?
vegetarians, and especially vegans Because vitamin is found primarily in foods derived from animals
In an unhealthy individual such as with pernicious anemia, how can they receive vitamin b12?
vitamin B12 must be given by injection to bypass the need for intestinal absorption; Alternatively, the vitamin may be delivered by nasal spray; absorption is rapid, high, and well tolerated.
What does the transfer of 1 carbon compound that arise during metabolism convert?
vitamin B12 to one of its coenzyme forms, synthesizes the DNA required for all rapidly growing cells, and regenerates the amino acid methionine from homocysteine
What are other key antioxidant nutrients?
vitamin E, beta-carotene, and selenium
What does oxygen destroy?
vitamin c
Excessive Bleeding disease
vitamin k defifiency
How is the structure of a vitamin different from proteins, carbs, and fats?
vitamins are individual units; not linked together
Which type of vitamin must be eaten more regularly?
water soluble vitamins
Which vitamins are hydrophilic?
water-soluble ones (the B vitamins: thiamin, riboflavin, niacin, biotin, pantothenic acid, vitamin , folate, and vitamin B12 and vitamin C;
What is vitamin C a bodyguard for?
water-soluble substances
Which vitamins travel freely in the blood?
water-soluble vitamins
When could a person become deficient in thiamin?
when they don't eat enough food
What are reliable sources of thiamin?
whole-grains or enriched products; legumes such as peas
When can folate deficiency rapidly develop and cause further damages to the GI tract?
with alcohol abuse
Does vitamin C have an UL?
yes
Can the body make choline?
yes from the amino acid methionine, but synthesis alone is insufficient
Do both types of beriberi appear together?
yes, with one set of symptoms predominating
What hinders the absorption of some nutrients?
zinc hinders copper and calcium absorption, iron hinders zinc absorption, calcium hinders magnesium and iron absorption, and magnesium hinders the absorption of calcium and iron.
Why can the GI tract become deteriorated without folate?
Because folate helps cell multiplication
Who needs supplements?
- People with specific nutrient deficiencies may need specific nutrient supplements. -People whose energy intakes are particularly low -Vegetarians who eat all-plant diets (vegans) and older adults with atrophic gastritis may need vitamin B12. - People who have lactose intolerance or milk allergies or who otherwise do not consume enough milk product -people in certain stages of the life cycle who have increased nutrient requirements may need specific nutrient supplements. -People who have inadequate intakes of milk or milk products, limited sun exposure, or heavily pigmented skin may need vitamin D. -People who have diseases, infections, or injuries or who have undergone surgery that interferes with the intake, absorption, metabolism, or excretion of nutrients may need specific nutrient supplements -People taking medications that interfere with the body's use of specific nutrients may need specific nutrient supplements
Where is a vitamin b12 deficiency common?
- among adults who use heartburn medications to suppress gastric acid production -elderly
What are signs of vitamin C deficiency?
- gums bleed easily around the teeth, and - - capillaries under the skin break spontaneously, producing pinpoint hemorrhages - The skin becomes rough, brown, scaly, and dry. - Muscles, including the heart muscle, degenerate. -Wounds fail to heal because scar tissue will not form. - Bone rebuilding falters; the ends of the long bones become softened, malformed, and painful, and fractures develop -teeth become loose as the cartilage around them weakens -Anemia and infections are common. -psychological signs, including hysteria and depression -Sudden death is likely, caused by massive internal bleeding
Who is at risk of thiamin deficiency?
- homeless - malnourished - those who derive most of their energy from empty kcalorie foods and beverages
Supplements with a USP verification logo have been tested by the US Pharmacopeia (USP) to ensure that the supplement:
-Contains the declared ingredients and amounts listed on the label -Does not contain harmful levels of contaminants -Will disintegrate and release ingredients in the body -Was made under safe and sanitary conditions
Women of childbearing age and who are capable of becoming pregnant should consume how much folate daily?
0.4 milligram (400 micrograms)
Why has the Food and Drug administration (FDA) mandated that grain products be fortified to deliver folate to the US population?
Because half of the pregnancies each year are unplanned and because neural tube defects occur early in development before most women realize they are pregnant
How much more times available is synthetic folate?
1.7 more times than naturally ocurring food
What does a high potency claim mean?
100% or more of the Daily Value for the nutrient in a single supplement and for at least two-thirds of the nutrients in a multinutrient supplement.
What must a person eat daily for several months to produce the symptoms of biotin deficiency?
2 dozen raw egg whites
What is the RDA for vitamin B12?
2.4 micrograms a day
What is the AI for biotin in adults?
30 μg/day
What percent of the US exceeds the UL for folate?
5%
Approximately how many milligrams of dietary tryptophan is needed to make 1 milligram of niacin?
60 milligrams
At about 100 milligrams per day, _____ percent of the population reaches tissue saturation.
95
Once the EAR (Estimated Average Requirement )is established, a recommendation can be made that will meet the needs of about what percent of people?
98% (The recommended Dietary Allowance (RDA)
What does (TPP) thiamin pyrophosphate help to convert?
A 5 carbon compound to a 4 carbon compound
What does vitamin C serve as?
A cofactor or acts as an antioxidant
What are vitamins?
A diverse group of essential nutrients that regulate most body processes involved in supporting growth and maintaining life
What can high intakes of folate mask?
A vitamin B12 deficiency, so it should not exceed 1 milligram daily
What is the UL for choline?
Adults: 3500 mg/day
Homocysteine
Amino acid that in high levels in the blood may enhance formation of blood clots or atherosclerotic lesions
What has been determined for biotin instead of an RDA?
An AI because there is insufficient research on biotin requirements
What recommendations have been set for pantothenic acid?
An AI that reflects that amount needed to replace daily losses
What is the disease for riboflavin deficiency?
Ariboflavinosis
What are the amounts of vitamin c needed based on the amounts needed to provide antioxidant protection?
At about 200 milligrams, absorption reaches a maximum, and there is little, if any, increase in blood concentrations at higher doses. Excess vitamin C is readily excreted.
What type of products should people avoid when buying supplements?
Avoid products that make "high potency" claims. More is not better
What should a person avoid when taking supplements?
Avoid supplements that, in a daily dose, provide more than the UL for any nutrient. Avoid preparations with more than 10 milligrams of iron per dose, except as prescribed by a physician
What food sources is vitamin C found in?
Citrus fruits, cabbage-type vegetables (such as brussels sprouts and cauliflower), dark green vegetables (such as bell peppers and broccoli), cantaloupe, strawberries, lettuce, tomatoes, potatoes, papayas, mangoes
Precursors
Compounds that can be converted into active vitamins
Anemia
Condition in which there is a reduced delivery of oxygen to cells
What happens to DNA without enough folate?
DNA damage interferes with the synthesis of the red blood cells as they attempt to divide and mature. The result is fewer, but larger, red blood cells that cannot carry oxygen or travel through the capillaries as efficiently as normal red blood cells
What are symptoms of vitamin B6 toxicity?
Depression, fatigue, irritability, headaches, nerve damage causing numbness and muscle weakness leading to an inability to walk and convulsions; skin lesions
What are dietary supplements regulated by?
FDA (Food and Drug Administration)
What are the coenzyme forms of riboflavin?
FMN (flavin mononucleotide) and FDA (flavin adenine dinucleotide)
A precursor is a conditionally essential vitamin. True False
False
Research shows that vitamin C can prevent and even cure the common cold. True False
False
Vitamins are measured in grams in food and in the body. True False
False
Water-soluble vitamins are stored in the body. True False
False