Nutrition and Health Chapter 7 Vitamins
Why was vitamin K named vitamin K?
It was discovered by a Danish scientist and it was named such because it is involved in blood clotting and clotting is spelled with a k in Danish
In regards to water soluble vitamins with absorption, what is it like?
Does not require bile
What are the symptoms of hypervitaminosis A?
Lack of appetite, dry, itchy, flaky skin, coarsening of the hair and hair loss, and liver damage
Is biotin toxic?
It appear to be nontoxic in amounts normally consumed
What are some signs of excess consumption of folate?
It can lead to insomnia, alteration in sleep patterns, irritability, and GI problems. Also it has been seen to alter zinc metabolism.
What happens when you have a deficiency of folate?
It can lead to microcytic, megaloblastic anemia, diarrhea, fatigue, depression and mental confusion
What is the functions of niacin?
It functions as a conenzyme in nearly all metabolic pathways yielding energy from carbohydrates, fats, proteins and alcohol. It also plays a role in tissue respiration, involved in the synthesis and breakdown of fats, and helps maintain healthy skin.
What happens if pregnant women take excessive amounts of vitamin A?
It has been associated with a high percentage of infants with birth defects and an increased risk of miscarriage
Is thiamin toxic?
It is considered non- toxic when taken orally either through the diet or in supplements. Injections of thiamin have been found to be toxic at higher levels.
What is the function of Thiamin?
It is integrally involved as a coenzyme in the catabolism of carbohydrates to yield energy.
What does biotin do?
It is involved in carbohydrate and lipid metabolism. It promotes synthesis of glucose and fatty acids and helps in the breakdown of some amino acids.
What are the functions of folate?
It is involved in protein and amino acid metabolism and also plays a critical role in the synthesis of DNA
What is the function of riboflavin?
It is involved in the metabolism of carbohydrates as well as of fats and proteins.
What is vitamin B12s function?
It is part of several coenzymes; one is involved in the synthesis of the amino acid methionine; another is involved in the use of energy found in proteins, fats, and carbohydrates
What are the functions of vitamin A?
It is required for the synthesis of rhodopsin and other light- receptor pigments in the eye and thus is essential for vision. Vitamin A is necessary for the adjustment of vision, particularly in dim light, called night vision. Vitamin A is also needed for normal growth and development to occur in the body, including the formation of bone and cartilage. Healthy epithelial or skin cells, which line surfaces inside and outside the body, require Vitamin A. This vitamin also plays a roles in reproduction, metabolism, and immune system function
What is an inactive pro- vitamin?
It must be converted to the active form before the vitamin can perform its functions in the body
What is a negative side effect of exercise?
It produces free radicals. Exercise of a high intensity or long duration can lead to oxidative stress in skeletal muscles, in the bloodstream, and possibly in other tissues, which can lead to a decrease in muscular strength as well as hastening the onset of fatigue.
Is riboflavin toxic?
Virtually non toxic in the amounts obtained from dietary sources
In regards to fat soluble vitamins and toxicity what is it like?
Vitamins A and D are quite toxic; vitamins E and K are relatively nontoxic
What makes riboflavin unstable?
When it is exposed to light. Therefore much of the riboflavin in milk is lost when milk is stores in clear containers
What are agents that can destroy thiamin?
Oxygen, heat, alkalis, and water
The entire constellation of symptoms that occur with a deficiency of niacin is known as?
Pellagra which means rough skin
Other than infants who else is at risk for a vitamin K deficiency?
People on long term antibiotic therapy sometimes develop a vitamin K deficiency because antibiotics can kill the bacteria produced in the intestine
What happens to people with untreated scurvy?
People will experience total muscular fatigue and become bedridden. Severe cases of scurvy are rarely seen in the U.S.
The combination of anemia and nerve damage that occurs with B12 deficiency is called what?
Pernicious anemia
What types of foods is beta- carotene present in?
Plant foods only such as carrots, sweet potatoes, apricots, romaine lettuce and peaches
What vitamins act as antioxidants in the body?
Vitamin, E, C, A, and beta- carotene
What does a deficiency of riboflavin lead to?
Ariboflavinosis and dermatitis
Vitamins contribute to what percentage of body weight?
1%
How long can the liver store B12?
2-3 year supply
It is illegal to sell folate in greater amounts of how many micrograms per pill without a prescription?
400 micrograms
What is the RDA for vitamin A for adults?
700 to 900 micrograms of RAE
What is ariboflavinosis?
A deficiency syndrome marked by inflammation of the mouth and tongue and cracking of the tissue around the corners of the mouth and on the lips
How long does it take for someone to get ariboflavinosis?
A person must consume a riboflavin poor diet for 2 months before getting these symptoms
Where can pantothenic acid be found?
A variety of plant and animal foods
What are the consequences of a vitamin a deficiency?
A vitamin A deficiency for several months may lead to night blindness and flaking skin
What are vitamins?
Chemically unrelated organic (carbon- containing) substances that are grouped together because each vitamin is essential in the diet in minute amounts
What prescription druge used to treat acne has a high dosage of vitamin A?
Accutane
How does one determine how much thiamin should be in their diet?
Active people generally need higher intakes of thiamin than sedentary ones
What are some functions of beta- carotene?
Acts as an antioxidant in the body and may counteract the destructive effects of free radicals produced by cellular oxygen use during exercise
What can a vitamin D deficiency lead to?
Affects the mineralization of bones and teeth. In children, vitamin D deficiency can lead to faulty calcification of bones, causing the bones to remain soft. Also rickets, which is also associated with improper development and formation of teeth, leading to an increased risk of dental caries.
What are the functions of vitamin D?
Aiding in the absorption, transport, and use of calcium and phosphorus. The small intestine, the bones, the kidneys and some other tissues are all involved in these functions. In some ways, vitamin D acts more like a hormone than a vitamin in the body. Its main function appears to be regulation of blood calcium levels so that appropriate amounts of calcium are available to body cells.
In our diets, vitamin D is found only in?
Animal foods
What are the functions of vitamin E?
As an antioxidant, vitamin E appears to protect polyunsaturated fatty acids in cell membranes from oxidation thereby reducing the risk of cells being damaged or destroyed. Vitamin E also helps to detoxify free radicals, which have been implicated in the development of heart disease and some types of cancers.
Dr. Lind called the factor present in lemon juice that prevented and cured scurvy the anti- scorbutic factor. Today what is anti- scorbutic known as?
Ascorbic acid, more commonly known as vitamin C
What is a coenzyme?
Associates with specific enzymes to form an active enzyme- coenzyme complex that acts as a catalyst in particular metabolic reactions in the body
The protein found in raw egg that can bind to biotin and render it inactive is known as?
Avidin
Why are infants and young children more prone to developing vitamin A toxicity?
Because their livers cannot store as much of the vitamin as adult livers can
List the Vitamin A and beta- carotene foods.
Beef liver, sweet potatoes, carrot, butternut squash, mango, spinach, turnip greens, dandelion green, collard green, kale, milk 2%, oysters, broccoli, escarole, apricot, boiled egg, acorn squash, peach, and butter.
What does a thiamin deficiency cause?
Beriberi
What is the most important vitamin A precursor?
Beta- carotene
Most vitamins function as?
Coenzymes
Vitamin C is required for the synthesis of what?
Collagen, the main structural protein in bones, teeth and connective tissue; carnitine, which is needed for fatty acid metabolism; and norepinephrine, a neurotransmitter involved in transmitting impulses along certain types of nerves.
Besides infants, people with certain medical conditions, like who, are more prone to developing vitamin E deficiencies?
Cystic fibrosis; malabsorption disorders; liver, gallbladder, and pancreatic disease; protein- energy malnutrition (in infants and children)
What are some of the things that vitamin D has said to prevent against?
Decreasing the risk of osteoporosis and may be beneficial for warding off certain forms of cancer (colon, rectal, colorectal), Alzheimer's disease and Crohn's Disease
What are the four Ds of pellagra?
Dermatitis, diarrhea, dementia and possibly death
The first nutrition research study was conducted by who?
Dr. James Lind, a surgeon in the British Navy in the mid-1700s
In regards to fat soluble vitamins and excretion, what is it like?
Excess amounts are not excreted in large amounts.
In regards to water soluble vitamins and excretion, what is it like?
Excess amounts are typically excreted in the urine
Is vitamin C toxic?
Excess vitamin C in the body is excreted in the urine and feces within approximately 3 hours of ingestion, regardless of size of the dose. Mega doses may lead to short- term diarrhea.
How is folate destroyed?
Exposure to heat, air, and ultra- violet light
What are free radicals?
Extremely reactive molecules that may lead to oxidative damage to proteins, lipids, and DNA, typically referred to as oxidative stress
Is it easier for people with dark skin or fair skinned to make an equivalent amount of vitamin D?
Fair skin
What are symptoms of vitamin C deficiency?
Fatigue, bleeding gums, loss of appetite, slow wound healing and an increased risk for tearing capillaries
Regular ingestion of as little as how many times the RDA of vitamin D can lead to toxicity symptoms?
Five times the RDA
What is folate sometimes referred to as?
Folic acid
What types of foods are preformed vitamin A found?
Foods of only animal origin such as liver, butter, eggs and fish oils
What types of foods are vitamin more commonly in?
Fruits and vegetables, and low in animal foods
What does the antioxidant activity of vitamin C do?
Has been found to protect lipids in the bloodstream and in cell membranes from oxidative damage. It also helps prevent destruction of folate (a B vitamin) in the body. Along with vitamin E, C appears to reduce the risk of cataract formation in the eye
What was Dr. Lind looking to find?
He wanted to identify factors that would reduce the incidence of scurvy among sailors at sea
Low levels of vitamin E in the body could lead to?
Heart disease
What are agents that can destroy pantothenic acid?
Heat, acids, alkalis and water
What are agents that can destroy vitamin c?
Heat, oxygen (air), alkalis (high pH) and water
What are agents that can destroy folic acid?
Heat, oxygen, and water
Where is biotin produced?
In bacteria in the intestine
Where is vitamin A found?
In foods as preformed vitamin A, which has vitamin activity and as precursors, called carotenoids, that can be converted to active Vitamin A in the body
What is osteomalacia?
In this disease, the calcium and phosphorus stored in bones are withdrawn, causing to become soft, porous and weak. Bone fractures and bone deformation are also common
The main dietary sources of Vitamin D in the U.S. are found?
In vitamin D fortified milk, margarine is also fortified with vitamin D in the U.S. and fatty fish
Who is most at risk for a vitamin E deficiency?
Infants born preamturely. Premature infants are often given special supplements to reduce their risk of developing hemolytic anemia. Intravenous vitamin E has caused toxic side effects in some infants and is not recommended.
Is vitamin B6 toxic?
Ingestion of very high levels of vitamin B6 for prolonged periods can cause severe damage to the nerves and an inability to control muscular movement.
What are the symptoms of a biotin deficiency?
Lack of appetite, nausea, an enlarged tongue, mental depression, pallor, loss of hair, dry scaly skin, and increased levels of cholesterol and bile in the blood
What are the major symptoms of vitamin D toxicity?
Lack of appetite, nausea, weakness, high blood pressure, excessive urination and thirst, excessive blood calcium levels and deposition of calcium into the soft tissues of the body and increased kidney stone formation and kidney failure
What happens when there is a B12 deficiency?
Leads to microcytic megaloblastic anemia. Prolonged deficiency of vitamin B12 leads to nerve damage caused by destruction of myelin sheaths.
What are the best sources of vitamin K?
Leafy green vegetables and bacteria in the human intestinal tract
What are agents that can destroy riboflavin?
Light and water
What are agents that can destroy vitamin B-12?
Light, strong acids (low pH), strong alkalis and water
What foods contain folate?
Liver, green leafy vegetables, legumes, oranges, corn, banana, peanut butter, and several other vegetables
What is beriberi?
Mainly affects the nervous and cardiovascular systems and can cause mental confusion, lack of appetite, muscular weakness, paralysis, edema increased heart rate and enlarged heart
What are the benefits of taking vitamin E?
May reduce the risk of developing certain types of cancer, including cancer of the stomach, esophagus and liver. Some evidence indicates also it may reduce the risk of developing cataracts
Are vitamins micronutrients or macronutrients?
Micronutrients
Is vitamin E toxic?
Most adults can tolerate oral doses up to 80 times their RDAs for months to years with no side effects. Premature infants given intravenously vitamin E have exhibited some toxic side effects. It is overall considered relatively nontoxic
In regards to water soluble intake frequency to meet requirements what is it like?
Most are needed daily
In regards to water soluble vitamins and toxicity what is it like?
Most are nontoxic or toxic only at very high intakes; niacin and vitamin B6 can be toxic
What are the reasons why most people get pernicious anemia?
Most the pernicious anemia seen in the U.S> is caused by inadequate absorption of B12. This condition results from insufficient production of intrinsic factor.
Where can vitamin B12 be found?
Naturally found only in animal foods. Some vegetarian foods such as fortified soy milk, are fortified with B12 to prevent deficiencies of this vitamin in strict vegetarians.
Is vitamin K toxic?
Naturally occurring forms of vitamin K appear to be nontoxic to humans. excessive intakes of synthetic supplements such as menadione have been shown to have toxic side effects in infants, including anemia and excessive levels of bile in the blood.
Are large doses of B12 considered toxic?
No
Are vitamins metabolized to yield energy or form body tissues?
No
Can beta- carotene cause hypervitaminosis A?
No
Does the body store large amounts of the water soluble vitamins?
No
Is biotin present in foods affected by exposure to light?
No
Is pantothenic acid affected by exposure to air or light?
No
Is vitamin B12 affected by exposure to heat or varying pH levels?
No
Does long exposure to sunlight lead to overproduction of vitamin D and toxicity?
No because the body regulates the amount of the provitamin synthesized in the skin
Is the loss of fat soluble vitamins during food preparation, processing or storage a serious concern?
No because these vitamins are relatively stable
Are pantothenic acid deficiencies common in humans?
No it has never been reported to occur naturally in humans because it is so widely distributed amongst are food supply
Can the body produce adequate amounts of methionine?
No it is an essential amino acid so we must get it from our food
Is likely to have a biotin deficiency?
No it is rare
Is it recommended to take beta- carotene as a supplement?
No it is suggested to get it from a diet rich in yellow- green fruits and vegetables
Does the liver store large amounts of folate?
No the liver stores small amounts of folate
Is the increased iron absorption associated with high levels of vitamin C supplementation good for everyone?
No, it can be harmful and life- threatening for others who already have high iron levels because of certain genetic diseases. Excess iron in the body can cause permeant damage to both the liver and heart.
Does the body store a lot of vitamin C?
No, so we need to consume it every day
Vitamin C increases absorption of what?
Nonheme iron and limits or regulates absorption of copper
Pernicious anemia is most prevalent in who?
Older adults because production of intrinsic factor decreases with age.
In adults, what can vitamin D deficiency lead to?
Osteomalacia
What are agents that can destroy biotin?
Oxygen, alkalis, and water
What are some good sources of vitamin E?
Polyunsaturated vegetable oils, wheat germ, leafy greens, almonds, peanuts and shellfish
Vitamins that exist in the inactive pro- vitamin forms are sometimes called what?
Precursors
Who is most prone to folate deficiency?
Pregnant women, which could lead to an abnormal development of the neural tube
What are some other functions of vitamin c?
Promote functioning of white blood cells and macrophages, immune responses, wound healing, and allergic reactions. Prolonged psychological stress can deplete the body's supply of vitamin C potentially decreasing immune- system responses.
The body's requirement for vitamin B6 increases as the intake of what increases?
Protein
Where can riboflavin be found?
Protein foods, milk, and milk products. Some green vegetables are also good sources
What is vitamin B6 sometimes called?
Pyridoxine
In regards to fat soluble vitamins with absorption, what is it like?
Requires bile and is aided by dietary fat; is prevented by laxatives containing mineral oil
How does one get hypervitaminosis A?
Results from long- term abuse of supplements. Chronic intake of vitamin A in amounts of ten times greater than the RDA can result in hypervitaminosis
What can a deficiency of vitamin C lead to?
Scurvy
In regards to fat- soluble vitamins stability, what is it like?
They are all relatively stable and not lost during cooking
Are vitamin B6 deficiencies common in the U.S.
They are rare
In regards to fat soluble intake frequency to meet requirements what is it like?
Usually are not needed daily because of high body stores
In regards to water- soluble vitamins stability, what is it like?
Some are destroyed by exposure to air, heat, or light; lost in cooking water
What happens when the body needs vitamin D?
Some of the stored provitamin is transported to the kidneys and converted into active vitamin D called calcitriol
What are some sources of thiamin?
Sunflower seeds, fortified grain products, legumes and fresh peas
What are some foods that contain vitamin C?
Sweet red pepper, orange juice, kiwi fruit, cantaloupe, green peppers, grapefruit, bok toy, strawberries, broccoli, spanish rice, potato with skin, spaghetti with tomato sauce dandelion greens, collard greens, watermelon chunks, cabbage, apple, salsa, pepperoni pizza, apple juice, hamburger with bun, eggplants boiled, bread, chicken fried and skim milk.
What happens with high niacin intakes?
The body may release histamine. The excess niacin competes with uric acid for excretion in the urine, thereby raising uric acid levels in the bloodstream. Liver damage and skin problems may result and blood glucose levels may increase.
What is the function of pantothenic acid?
The coenzyme form of pantothenic acid, called coenzyme A, assists in many reactions involved in carbohydrate, lipid and protein metabolism.
Where are fat soluble vitamins often present?
The fat portion of foods
The conversion of beta- carotene (or pro- vitamin A) occurs primarily where in the body?
The intestinal wall
Where are fat soluble vitamins often stored in the body?
The liver and adipose tissue
What happens in vitamin E deficiency?
The membranes of the red blood cells suffer oxidative damage and break because they are not protected by the antioxidant activity of vitamin E. The premature destruction of red blood cells leads to hemolytic anemia.
Is niacin toxic?
The niacinamide form of niacin is nontoxic, but high intakes of nicotinic acid form can cause a variety of unwanted side effects.
What is the major symptom of vitamin E deficiency seen in adults?
The premature destruction of red blood cells
What is xerophthalmia?
The symptoms include dry, hard cornea. If this condition is left untreated, damage to the cornea progresses, leading to a softening of the cornea and eventually blindness.
How long can adults store vitamin A in the liver for?
They can store up to a years supply of vitamin A in the liver
Vitamin K deficiencies are rare, but why may a newborn infant develop a vitamin K deficiency?
They lack intestinal bacteria and therefrom do not obtain any vitamin K from this source. Newborns are not always fed immediately after birth and breast milk is relatively low in vitamin K.
What types of problems can free radicals induce?
They may be involved in the development of heart disease and certain types of cancer, as well as the aging process
What is the purpose of an antioxidant?
They protect cells against oxidative destruction by free radicals
In regards to fat soluble vitamins and transport in blood stream what is it like?
They travel along with blood lipids
In regards to water soluble vitamins and transport in blood stream what is it like?
They travel on their own
If a grapefruit is cut in half or a container of orange juice is refrigerated uncovered and exposed to air what will happen to the vitamin c in these products?
They will lose it
Is thiamin stable?
Thiamin is unstable and loses its activity when exposed to air, heat or a high pH
What happens after vitamin A stores have exceeded?
This leads to vitamin A toxicity or hypervitaminosis
Who is most likely to get pellagra?
Those with low dietary intakes of niacin whose skin is exposed to intense sunlight
What is the major function of vitamin K?
To promote coagulation of blood after injury, thereby preventing hemorrhaging. Vitamin K is necessary for the synthesis of prothrombin, an inactive form of thrombin. Thrombin in turn catalyzes the conversion of fibrinogen into fibrin, an insoluble protein that forms the mesh- like substance of a blood clot.
Why do smokers have a higher RDA for vitamin C?
Tobacco smoke appears to increate the rate of turnover and metabolism of vitamin C, thus leading to low levels of the vitamin in the bloodstream
Is pantothenic acid toxic?
Toxicity from high intakes of pantothenic acid are rare. Intakes of 10 to 20 grams per day occasionally result in diarrhea and fluid retention
True or false, metabolism of all the energy- supplying nutrients (carbs., lipids, and protein) depends on vitamin coenzymes?
True
What was the first vitamin discovered?
Vitamin A after the first letter in the alphabet
What are the fat soluble vitamins?
Vitamin A, D, E, and K
What are some of the functions of vitamin B6?
Vitamin B6 functions as a coenzyme in the metabolism of proteins and amino acids. In the absence of vitamin B6 the body could not produce the non- essential amino acids. Synthesis of many neurotransmitters also depends on this vitamin as does metabolism of some fats.
What are the water soluble vitamins?
Vitamin C, thiamin, riboflavin, niacin, vitamin B-6, folate, vitamin B-12, biotin and pantothenic acid
What is the most toxic vitamin?
Vitamin D
Who are people at risk for developing osteomalacia?
Women who have had multiple pregnancies coupled with poor dietary intakes and infrequent exposure to the sun. Lactose- intolerant people with dark skin who live in smoggy cities are likely to develop vitamin D deficiency because they drink little milk and produce relatively small amounts of vitamin D from exposure to the sun.
What is a long term deficiency of vitamin A?
Xerophthalmia
Are both inactive vitamin D formed in the skin and vitamin D absorbed from dietary sources transported through the bloodstream to the liver?
Yes
Do most Americans meet the RDA for vitamin B12?
Yes
Do people who produce insufficient amounts of intrinsic factor develop b12 deficiency regardless of their dietary intake of this vitamin?
Yes
Does the FDA require that all enriched grains be fortified with folate?
Yes
Does the body's need for niacin increase as the intake of kilocalories increases?
Yes
Is niacin a stable vitamin?
Yes
Is vitamin C an antioxidant?
Yes
Do many Americans have inadequate folate intake?
Yes because low consumption of vegetables and loss of the vitamin in cooking
Can the human body produce vitamin D?
Yes from cholesterol present in the skin, this conversion depends on exposure of the skin to the ultraviolet rays in sunlight and yields inactive provitamin D
Are alcoholics at risk for vitamin A deficiency?
Yes people with liver disorders or conditions that impair absorption are also at an increased risk of developing vitamin A deficiency.
Are young children or are adults at a greater risk for developing vitamin A deficiency?
Young children
What are agents that can destroy vitamin B-6?
oxygen, ultraviolet light, alkalis, and water