A Comprehensive Introduction to Vitamins and its chemistry, source, RDA, classification, deficiency states and biological importance. This will give readers a overall insight to this topic.
2. Vitamins
Vitamins are organic nutrients that are required in small quantities for a variety of
biochemical functions for normal maintenance of optimum growth and health and
which generally cannot be synthesized in the body and must be supplied by the diet.
In ancient Egypt: Feeding of patients with liver to prevent night blindness (now
known as vitamin A deficiency)
In 1749, the prevention of scurvy by citrus foods, was first discovered by the
Scottish surgeon James Lind.
Hopkins coined the term accessory factors to unknown and essential
nutrients present in the natural foods. In 1913 active principle (an amine)
isolated from rice polishing and, later in yeast, by Funk which could cure
beriberi in pigeons. He coined the term vitamine (greek: vita-life) to the
accessory factors with a belief that all of them were amines. It was later
realised that only few of them are amines.
History
3. Year of discovery Vitamin Source
1909 Vitamin A (Retinol) Cod liver oil (a fish)
1912 Vitamin B1 (Thiamin) Rice bran
1912 Vitamin C (Ascorbic Acid) Lemons
1918 Vitamin D (Calciferol) Cod liver oil
1920 Vitamin B2 (Riboflavin) Eggs
1922 Vitamin E (Tocopherol) Wheat germ oil
1926 Vitamin B12 (Siano Cobalamin) Liver
1929 Vitamin K (Phylloquinone) Luzerne
1931 Vitamin B5 (Pantothenicacid) Liver
1931 Vitamin B7 (Biotin) Liver
1934 Vitamin B6 (Pyridoxine) Rice bran
1936 Vitamin B3 (Niacin) Liver
1941 Vitamin B9 (Folic acid) Liver
The discovery of Vitamins and their sources
4. Biological importance of vitamins
1. Essential for growth, maintenance and
reproduction
2. Fat soluble vitamins are required for normal and colour vision, blood
clotting, bone formation and maintenance of membrane structure.
3. Most of the water soluble vitamins function as coenzymes
4. Vitamins A and D act as steroid hormones.
5. Lack of vitamin in the diet produce characteristic deficiency
symptoms
6. Some drugs and compounds present in natural
sources act as antivitamins.
7. Some vitamin analogs are used as drugs
6. 1) Water- soluble vitamins: can dissolve in aqueous solutions. these are not stored in the body and
can readily excreted. used as cofactors by many enzymes. There are 9 water soluble vitamins.
e.g. Vitamin C and vitamin B-complex.
2) Fat-soluble vitamins: can dissolve in lipid solutions but not in aqueous solutions. these are
absorbed through the intestinal tract with the help of lipids (fat) and stored in the body. There
are 4 types of fat soluble vitamins. Important in vision, bone formation, antioxidants and blood
clotting. e.g. Vitamin A, D, E, & K
Properties Water soluble vitamins Fat soluble vitamins
Solubility Water soluble Fat soluble
Absorption Simple Along with lipids
Storage *No storage Stored in liver
Excretion Excreted Not excreted
Excess intake Nontoxic Toxic
Deficiency Manifests rapidly Manifests slowly
Treatment Regular dietary supply Single large dose
7. Water- soluble vitamins
Thiamin (thiamine), or vitamin B1, is a water-soluble vitamin found naturally in some
foods, added to foods, and sold as a supplement. Thiamin plays a vital role in the growth
and function of various cells. Only small amounts are stored in the liver, so a daily intake of
thiamin-rich foods is needed.
Thiamine (Vitamin B1)
Dietary allowance: The Recommended Dietary Allowance (RDA) for men ages 19 and
older is 1.2 mg daily, and for women in the same age range 1.1 mg daily. For pregnancy and
lactation, the amount increases to 1.4 mg daily.
8. Deficiency
A more severe thiamin deficiency can lead to beriberi, which causes muscle loss and
diminished feeling in the hands and feet (peripheral neuropathy). Because beriberi
impairs reflexes and motor function, it can eventually lead to deadly fluid build-up in the
heart and lower limbs. Another result of serious thiamin deficiency often seen with
alcohol abuse is Wernicke-Korsakoff syndrome that may cause confusion, loss of
muscle coordination, and peripheral neuropathy. Both types of deficiency are also seen
with compromised gastrointestinal conditions such as celiac disease or bariatric surgery,
or those with HIV/AIDs. Treatment is high- dose supplements or injections through a
vein along with a balanced diet.
Symptoms appearing with mild to moderate deficiency:
Weight loss
Confusion, memory loss
Muscle weakness
Peripheral neuropathy
Lowered immunity
Food Sources
Thiamin is found naturally in meats, fish, and whole grains. It is also added to breads,
cereals, and baby formulas. Fortified breakfast cereals, Pork, Fish, Beans, lentils, Green
peas, Enriched cereals, breads, noodles, rice, Sunflower seeds, Yogurt
9. Riboflavin (Vitamin B2)
Made of the sugar alcohol ribitol and flavin, Part of the coenzymes flavin adenine
dinucleotide (FAD) and flavin mononucleotide (FMN). Vitamin B2 is a water-soluble
vitamin that is flushed out of the body daily, so it must be restored each day. Riboflavin is a
vitamin that is needed for growth and overall good health. It helps the body break down
carbohydrates, proteins and fats to produce energy, and it allows oxygen to be used by the
body.
Dietary allowance: recommended daily allowance
(RDA) of riboflavin is dependent on age, gender and
reproductive status. RDA is 1.3 milligrams daily for
men and 1.1 mg for women. As a supplement,
riboflavin is usually included in multivitamins and B-
complex vitamins. It also is available separately in
doses of 25 mg, 50 mg and 100 mg.
10. Food Sources
The best way to get this vitamin is by eating foods that are rich in riboflavin. Riboflavin is
found in eggs, nuts, dairy products, meats, broccoli, brewer's yeast, Brussel sprouts, wheat
germ, wild rice, mushrooms, soybeans, green leafy vegetables and whole grain and
enriched cereals and bread,
Deficiency
Deficiency can cause anemia, sore throat, mouth or lip sores, inflammation of the skin
(dermatitis) and swelling of soft tissue in the mouth (cheilosis and glossitis).
11. Niacin (Vitamin B3)
Vitamin B3, also known as niacin, plays a key role in skin, digestive, and mental health,
and supports the functions of more than 200 enzymes in the body.
Vitamin B3 is a combination of two chemicals: nicotinic acid and nicotinamide. The
body breaks these chemicals down to produce two additional chemicals: NAD and NADP
involved in oxidation- reduction reactions.
Dietary allowance: Children: between 2-16 milligrams daily, depending on age Men: 16
milligrams daily and Women: 14 milligrams daily
Food Sources
Niacin is found in a variety of foods,
especially meat, poultry, fish, nuts and
legumes.
12. Deficiency
Severe vitamin B3 deficiency causes a condition called pellagra.
Pellagra affects the skin, nervous system, digestive system, and mucous membranes, such
as the eyes and nose.
Symptoms of pellagra include:
Symmetrical lesions on both sides of the body. The lesions are most visible at pressure
points and on areas of the skin exposed to the sun. Some people develop lesions that cover
their entire hands or feet.
Less severe cases of vitamin B3 deficiency may cause less serious symptoms in the skin,
nervous system, digestive system, or mucous membranes. Those symptoms might include:
irritated or red skin, headaches, fatigue, unexplained digestive problems, mood issues,
such as anxiety or depression, changes in thinking or the ability to concentrate, dizziness
and poor circulation
13. Pantothenic Acid (Vitamin B5)
Vitamin B5, also called pantothenic acid, is one of the most important vitamins for human
life. It’s necessary for making blood cells, and it helps you convert the food you eat into
energy.
Vitamin B5 is one of eight B vitamins. All B vitamins help you convert the protein,
carbohydrates, and fats you eat into energy.
Is part of coenzyme A needed for energy production as wellas glucose and cholesterol
Synthesis.
Dietary allowance:
Age 0-6 months: 1.7 milligrams per day
Age 7-12 months 1.8 mg/day
Age 1-3 years: 2 mg/day
Age 4-8 years: 3 mg/day
Age 9-13 years: 4 mg/day
Age 14 and older: 5 mg/day
14. Food Sources
Broccoli, members of the cabbage family, white and sweet potatoes, whole-grain cereals,
mushrooms, nuts, beans, peas, lentils, meats, poultry, dairy products and eggs
Deficiency
Symptoms of a vitamin B5 deficiency are likely to include:
Headache
Fatigue
Irritability
Impaired muscle coordination
Gastrointestinal problems
15. Pyridoxine (Vitamin B6)
Vitamin B6, or pyridoxine, is a water-soluble vitamin found naturally in many foods, as well
as added to foods and supplements. Pyridoxal 5’ phosphate (PLP) is the active coenzyme
form and most common measure of B6 blood levels in the body. PLP is a coenzyme that
assists more than 100 enzymes to perform various functions, including the breakdown of
proteins, carbohydrates, and fats; maintaining normal levels of homocysteine (since high
levels can cause heart problems); and supporting immune function and brain health.
Vitamin B6 has been widely studied for its role in
disease prevention. The vitamin in supplement form
shows the most promise for the treatment of
pregnancy-induced nausea, but such use should
only occur under the supervision of a physician.
Adequate blood levels of B6 may be associated with
lower risk of cancers, compared to low blood levels.
However, the use of separate B6 supplements (apart
from the RDA amounts in typical multivitamin
preparations) is inconclusive and not
recommended.
16. Deficiency
A vitamin B6 deficiency most often occurs when other B vitamins in the body are low,
particularly vitamin B12 and folic acid. A mild deficiency may have no symptoms, but a
more severe or prolonged deficiency can exhibit the following:
Microcytic anemia, Skin conditions, Depression, Confusion, Lowered immunity
Certain conditions can increase the risk of developing a deficiency by interfering
with the absorption of vitamin B6:
Kidney disease, Autoimmune intestinal disorders like celiac disease, ulcerative
colitis, and Crohn’s disease, Autoimmune inflammatory disorders such as rheumatoid
arthritis, Alcoholism
Dietary allowance: The Recommended Dietary Allowance (RDA) for men ages 14-50
years is 1.3 mg daily; 51+ years, 1.7 mg. The RDA for women ages 14-18 years is 1.2 mg; 19-50
years, 1.3 mg; and 51+ years, 1.5 mg. For pregnancy and lactation, the amount increases to
1.9 mg and 2.0 mg, respectively.
Food Sources
Vitamin B6 is found in a variety of animal and plant foods. Beef liver, Tuna, Salmon,
Fortified cereals, Chickpeas, Poultry, Some vegetables and fruits, especially dark leafy
greens, bananas, papayas, oranges, and cantaloupe
17. Biotin (Vitamin B7)
It is a water-soluble B vitamin found naturally in some foods and also in supplements.
Biotin plays a vital role in assisting enzymes to break down fats, carbohydrates, and
proteins in food. It also helps to regulate signals sent by cells and the activity of genes.
Dietary allowance: An RDA (Recommended
Dietary Allowance) does not exist for biotin
because there is not enough evidence to suggest a
daily amount needed by most healthy people.
Instead, there is an AI (Adequate Intake) level,
which is assumed to ensure nutritional adequacy.
The AI for biotin for men and women 19 years and
older and for pregnant women is 30 micrograms
daily. Lactating women need 35 micrograms daily.
Food Sources: Beef liver, Eggs (cooked), Salmon, Avocados, Pork, Sweet potato, Nuts,
seeds
18. Deficiency
A biotin deficiency in the U.S. is rare, as most people eat enough biotin in a varied diet.
Alcoholism can increase the risk of biotin deficiency and many other nutrients as alcohol
can block their absorption, and also because alcohol abuse is generally associated with a
poor dietary intake. About a third of pregnant women show a mild biotin deficiency despite
eating adequate intakes, though the exact reason is not clear.
Symptoms appearing with a biotin deficiency:
-Thinning hair
-Scaly skin rashes around eyes, nose, mouth
-Brittle nails
19. Folic Acid (Vitamin B9)
Folate is the natural form of vitamin B9, water-soluble and naturally found in many foods.
It is also added to foods and sold as a supplement in the form of folic acid; this form is
actually better absorbed than that from food sources—85% vs. 50%, respectively. Folate
helps to form DNA and RNA and is involved in protein metabolism. It plays a key role in
breaking down homocysteine, an amino acid that can exert harmful effects in the body if it
is present in high amounts. Folate is also needed to produce healthy red blood cells and is
critical during periods of rapid growth, such as during pregnancy and fetal development.
Dietary allowance
The Recommended Dietary Allowance for folate
is listed as micrograms (mcg) of dietary folate
equivalents (DFE). Men and women ages 19
years and older should aim for 400 mcg DFE.
Pregnant and lactating women require 600 mcg
DFE and 500 mcg DFE, respectively. People who
regularly drink alcohol should aim for at least
600 mcg DFE of folate daily since alcohol can
impair its absorption.
20. Food Sources
Dark green leafy vegetables (turnip greens, spinach, romaine lettuce, asparagus, Brussels
sprouts, broccoli), Beans, Peanuts, Sunflower seeds, Fresh fruits, fruit juices, Whole grains,
Liver, Seafood, Eggs, Fortified foods and supplements
Deficiency
A folate deficiency is rare because it is found in a wide range of foods.
Signs of deficiency can include: megaloblastic anemia (a condition arising from a lack of
folate in the diet or poor absorption that produces less red blood cells, and larger in size
than normal); weakness, fatigue; irregular heartbeat; shortness of breath; difficulty
concentrating; hair loss; pale skin; mouth sores.
21. Cobalamin (Vitamin B12)
Vitamin B12, or cobalamin, is naturally found in animal foods. It can also be added to foods
or supplements. Vitamin B12 is needed to form red blood cells and DNA. It is also a key
player in the function and development of brain and nerve cells.
Vitamin B12 binds to the protein in the foods we eat. In the stomach, hydrochloric acid and
enzymes unbind vitamin B12 into its free form. From there, vitamin B12 combines with a
protein called intrinsic factor so that it can be absorbed further down in the small intestine.
Dietary allowance: The Recommended Dietary Allowance for men and women ages
14 years and older is 2.4 micrograms (mcg) daily. For pregnancy and lactation, the
amount increases to 2.6 mcg and 2.8 mcg daily, respectively.
Food Sources: Fish, shellfish, Liver, Red meat, Eggs, Poultry, Dairy products such as
milk, cheese, and yogurt, Fortified nutritional yeast, Fortified breakfast cereals,
Enriched soy or rice milk
22. Deficiency
Signs of deficiency may include:
Megaloblastic anemia— a condition of larger
than normal sized red blood cells and a smaller
than normal amount; this occurs because there
is not enough vitamin B12 in the diet or poor
absorption
Pernicious anemia- a type of megaloblastic
anemia caused by a lack of intrinsic factor so
that vitamin B12 is not absorbed
-Fatigue, weakness
-Nerve damage with numbness,
tingling in the hands and legs
-Memory loss, confusion
-Dementia
-Depression
-Seizures
23. Ascorbic Acid (Vitamin C)
Vitamin C, or ascorbic acid, is a water-soluble vitamin. This means that it dissolves in
water and is delivered to the body’s tissues but is not well stored, so it must be taken
daily through food or supplements.
Vitamin C plays a role in controlling infections
and healing wounds, and is a powerful
antioxidant that can neutralize harmful free
radicals. It is needed to make collagen, a fibrous
protein in connective tissue that is weaved
throughout various systems in the body:
nervous, immune, bone, cartilage, blood, and
others. The vitamin helps make several
hormones and chemical messengers used in the
brain and nerves.
Dietary allowance: The Recommended Dietary Allowance for adults 19 years and older
is 90 mg daily for men and 75 mg for women. For pregnancy and lactation, the amount
increases to 85 mg and 120 mg daily, respectively. Smoking can deplete vitamin C levels in
the body, so an additional 35 mg beyond the RDA is suggested for smokers.
24. Deficiency
Vitamin C deficiency is rare in developed countries but may occur with a limited diet that
provides less than 10 mg daily for one month or longer. In developed countries, situations
at greatest risk for deficiency include eating a diet restricted in fruits and vegetables,
smoking or long-term exposure to second hand smoke, and drug and alcohol abuse. The
following are the most common signs of a deficiency.
Scurvy, the hallmark disease of severe vitamin C deficiency, displays symptoms resulting
from loss of collagen that weakens connective tissues:
-Skin spots caused by bleeding and bruising from broken blood vessels
-Swelling or bleeding of gums, and eventual loss of teeth
-Hair loss
-Delayed healing of skin wounds
-Fatigue, malaise
-Iron-deficiency anemia due to decreased absorption of non-heme iron
Food Sources
Fruits and vegetables are the best sources of this vitamin. Citrus (oranges, kiwi, lemon,
grapefruit) Bell peppers, Strawberries, Tomatoes, Cruciferous vegetables (broccoli, Brussels
sprouts, cabbage, cauliflower) White potatoes
25. VitaminA
Fat -soluble vitamins
Vitamin A also stimulates the production and activity of white blood cells, takes part in
remodeling bone, helps maintain healthy endothelial cells (those lining the body’s
interior surfaces), and regulates cell growth and division such as needed for
reproduction.
The two main forms of vitamin A in the human diet are preformed vitamin A (retinol,
retinyl esters), and provitamin A carotenoids such as beta-carotene that are converted
to retinol. Preformed vitamin A comes from animal products, fortified foods, and
vitamin supplements. Carotenoids are found naturally in plant foods. There are other
types of carotenoids found in food that are not converted to vitamin A but have health-
promoting properties; these include lycopene, lutein, and zeaxanthin.
Dietary allowance: The
Recommended Dietary
Allowance for adults 19 years
and older is 900 mcg RAE for
men (equivalent to 3,000 IU)
and 700 mcg RAE for women
(equivalent to 2,333 IU)
26. Food Sources
Many breakfast cereals, juices, dairy products, and other foods are fortified with retinol
(preformed vitamin A). Many fruits and vegetables and some supplements contain beta-
carotene, lycopene, lutein, or zeaxanthin.
Leafy green vegetables (kale, spinach, broccoli), orange and yellow vegetables
(carrots, sweet potatoes, pumpkin and other winter squash, summer squash)
Tomatoes, Red bell pepper, Cantaloupe, mango, Beef liver, Fish oils, Milk, Eggs, Fortified
foods
Deficiency
Vitamin A deficiency is rare in Western countries but may occur. Conditions that interfere
with normal digestion can lead to vitamin A malabsorption such as celiac disease, Crohn’s
disease, cirrhosis, alcoholism, and cystic fibrosis. Also at risk are adults and children who
eat a very limited diet due to poverty or self-restriction. Mild vitamin A deficiency may
cause fatigue, susceptibility to infections, and infertility. The following are signs of a more
serious deficiency:
-Xerophthalmia, a severe dryness of the eye that if untreated can lead to blindness
-Nyctalopia or night blindness
-Irregular patches on the white of the eyes
-Dry skin or hair
27. Walds Visual Cycle (Rhodopsin Cycle)
The retina of the eye contains two types of receptor cells,
Rod cells which are responsible for dim light vision &
the cones, responsible for bright light vision. Cones are
also responsible for colour perception. The deficiency of
cone pigments makes the individual colour blind. In
retinal pigments, the rod cells contain rhodopsin. Under
the influence of light, rhodopsin is converted to
lumirhodopsin which is further converted into
metarhodopsin. Then hydrolysed to protein opsin &
trans retinal. Trans-Retinal (transretinene) is inactive in
the synthesis of rhodopsin; it must be converted to the
active cisisomer. In the eye, the trans-retinal is reduced
to trans-retinol by the enzyme retinal reductase &
NADH. The trans retinol which is too inactive in
rhodopsin synthesis is passed into blood stream, and
then carried to liver. It is then converted to cis isomer. In
dim light active cis-retinol from the blood enters the
retina where it is oxidized to cis-retinal by reverse action
of retinal reductase in the presence of NAD+. Finally,
the cis-retinal combines with protein opsin to give back
rhodopsin and thus cycle is repeated.
28. Vitamin D
Vitamin D is both a nutrient we eat and a hormone our bodies make. Few foods are
naturally rich in vitamin D, so the biggest dietary sources of vitamin D are fortified foods
and vitamin supplements. Good sources include dairy products and breakfast cereals (both
of which are fortified with vitamin D), and fatty fish such as salmon and tuna.
Dietary allowance: For most people, the
best way to get enough vitamin D is taking a
supplement, but the level in most
multivitamins (400 IU) is too low.
Encouragingly, some manufacturers have
begun adding 800 or 1,000 IU of vitamin D
to their standard multivitamin
preparations.
Two forms of vitamin D are used in supplements: vitamin D2 (“ergocalciferol,” or pre-
vitamin D) and vitamin D3 (“cholecalciferol”). Vitamin D3 is chemically
indistinguishable from the form of vitamin D produced in the body.
The body also manufactures vitamin D from cholesterol, through a process triggered by the
action of sunlight on skin, hence its nickname, “the sunshine vitamin.”
29. Functions of vitamin D
Vitamin D has many important functions, including:
Supporting bone health by enabling the absorption of calcium
Promoting muscle health
Modulating the immune system
Aiding cell growth
Reducing inflammation, which helps prevent diseases such as rheumatoid
arthritis and psoriasis
Regulating blood pressure and supporting cardiovascular health
Foods sources of vitamin D
Good dietary sources of vitamin D include:
oily fish, such as mackerel or salmon, beef liver, cheese, mushrooms, egg yolks, fortified
foods, including some breakfast cereals, orange juice, milk, soy drinks, and margarine
30. Deficiency
A vitamin D deficiency may produce no symptoms, or symptoms may take several years
to appear. However, it may increase the risk of long term health problems.
In time, low levels of vitamin D can lead to:
Osteoporosis: The bones become thin or brittle. The first sign may be a bone breaking
easily as a result of minor trauma. It often affects older people.
Osteomalacia: This can affect children. The bones become soft, resulting in bone
deformities, short stature, dental problems, fragile bones, and pain when walking.
Researchers are looking into whether other symptoms or conditions, such
as depression, bone pain, and weakness, may result from low vitamin D levels and can
low vitamin D levels lead to hair loss
31. Vitamin E
Vitamin E is a fat-soluble vitamin with several forms, but alpha-tocopherol is the only
one used by the human body. Its main role is to act as an antioxidant, scavenging loose
electrons—so-called “free radicals”—that can damage cells. [1] It also enhances immune
function and prevents clots from forming in heart arteries. Antioxidant vitamins,
including vitamin E, came to public attention in the 1980s when scientists began to
understand that free radical damage was involved in the early stages of artery-clogging
atherosclerosis, and might also contribute to cancer, vision loss, and a host of other
chronic conditions. Vitamin E has the ability to protect cells from free radical damage as
well as stop the production of free radical cells entirely. However, conflicting study
results have dimmed some of the promise of using high dose vitamin E to prevent
chronic diseases.
Dietary allowance:The Recommended
Dietary Allowance (RDA) for vitamin E for
males and females ages 14 years and older
is 15 mg daily (or 22 international units,
IU), including women who are pregnant.
Lactating women need slightly more at 19
mg (28 IU) daily.
32. Food Sources
Vitamin E is found in plant-based oils, nuts, seeds, fruits, and vegetables. Wheat germ oil
Sunflower, safflower, and soybean oil, Sunflower seeds, Almonds, Peanuts, peanut butter
Beet greens, collard greens, spinach, Pumpkin, Red bell pepper, Asparagus, Mango,
Avocado
Deficiency
Because vitamin E is found in a variety of foods and supplements, a deficiency in the U.S. is
rare. People who have digestive disorders or do not absorb fat properly (e.g., pancreatitis,
cystic fibrosis, celiac disease) can develop a vitamin E deficiency. The following are
common signs of a deficiency:
-Retinopathy (damage to the retina of the eyes that can impair vision)
-Peripheral neuropathy (damage to the peripheral nerves, usually in the hands or
feet, causing weakness or pain)
-Ataxia (loss of control of body movements)
-Decreased immune function
33. Vitamin K
Vitamin K is a fat-soluble vitamin that comes in two forms. The main type is called
phylloquinone, found in green leafy vegetables like collard greens, kale, and spinach.
The other type, menaquinones, are found in some animal foods and fermented foods.
Menaquinones can also be produced by bacteria in the human body.
Vitamin K helps to make various proteins that are needed for blood clotting and the
building of bones. Prothrombin is a vitamin K-dependent protein directly involved with
blood clotting. Osteocalcin is another protein that requires vitamin K to produce
healthy bone tissue.
Vitamin K is found throughout the body including the liver, brain, heart, pancreas, and
bone. It is broken down very quickly and excreted in urine or stool. Because of this, it
rarely reaches toxic levels in the body even with high intakes, as may sometimes occur
with other fat-soluble vitamins.
Dietary allowance:
AI: An “adequate intake” (AI) is used when there is not enough evidence to establish a
Recommended Dietary Allowance (RDA). The AI amount is estimated to ensure nutritional
adequacy. For adults 19 years and older, the AI for vitamin K is 120 micrograms (mcg) daily
for men and 90 mcg for women and for those who are pregnant or lactating.
34. Food Sources
Phylloquinone: Green leafy vegetables including
collard and turnip greens, kale, spinach,
broccoli, Brussels sprouts, cabbage, lettuces, Soybean
and canola oil Salad dressings made with soybean or
canola oil, Fortified meal replacement shakes
Menaquinones: Natto (fermented soybeans), Smaller
amounts in meat, cheese, eggs
Deficiency
Vitamin K deficiency in adults is rare, but may occur in people taking medications that
block vitamin K metabolism such as antibiotics, or in those with conditions that cause
malabsorption of food and nutrients. A deficiency is also possible in newborn infants
because vitamin K does not cross the placenta, and breast milk contains a low amount. The
limited amount of blood clotting proteins at birth increases the risk of bleeding in infants
if they are not given vitamin K supplements. The following are the most common signs of a
deficiency:
-A longer time for blood to clot or a prolonged prothrombin time (as measured in
a physician’s office)
-Bleeding
-Hemorrhaging
-Osteopenia or osteoporosis
38. Vitamin Food Sources
Vitamin B6
Pyridoxin
Potatoes, bananas
100% bran, instant oatmeal
Meat, fish, poultry, liver, soybeans, chickpeas, lentils, pistachio, nuts,
sunflower seeds
Vitamin B12
Cobalamin
Milk, cheese, yogurt, fortified soy or rice beverages
Meat, fish, poultry, liver, eggs, fortified soy products
Vitamin B9
Folate
Asparagus, cooked spinach, romaine lettuce, Brussels sprouts, beets,
broccoli, corn, green peas, oranges, orange juice
Bread, enriched pasta, wheat germ
Liver, dried beans, soybeans, chickpeas, lentils, sunflower seeds, flaxseeds
*Folic acid is the type of folate found in Vitamin supplements and fortified
foods.
Vitamin C
Ascorbic acid
Citrus fruits such as oranges, grapefruits and
their juices, kiwi, strawberries, mangoes, papaya
Red, yellow and green peppers, broccoli, Brussels sprouts, tomatoes, raw
dark leafy vegetables
39. Vitamin Food Sources
Vitamin A
Carotenoids
Liver, some fish
Milk, cheese
Cantaloupe, pink grapefruit, tomatoes, broccoli, dark green leafy vegetables
like spinach, beet greens and Swiss chard, dark orange vegetables such as
carrots and sweet potatoes
Vitamin D
Calciferol
Milk, fortified soy and rice beverages
Fortified margarine
Some fish, eggs, organ meats, fish liver oils
Vitamin E Vegetable oils
Avocados, leafy green vegetables
Wheat germ, sunflower seeds, some nuts, peanut butter
Vitamin K Broccoli, soybeans, dark green leafy vegetables such as kale, collards,
turnip/beet greens and spinach
40. RDA /RDI (Recommended Dietary Allowance/Intake) of vitamins
Vitamin name RDA for adult male
Vitamin B1 1.2 mg
Vitamin B2 1.3 mg
Vitamin B3 16.0 mg
Vitamin B5 5.0 mg
Vitamin B6 1.3–1.7 mg
Vitamin B12 2.4 µg
Vitamin C 90.0 mg
Vitamin name RDA for adult male
Vitamin A 900 µg
Vitamin D 10 µg
Vitamin E 15.0 mg
Vitamin K 120 µg
41. Vitamin name Deficiency disease
Vitamin B1 Beriberi, Wernicke syndrome
Vitamin B2 Ariboflavinosis, Glossitis, Angular stomatitis
Vitamin B3 Pellagra
Vitamin B5 Paresthesia
Vitamin B6 Anemia, peripheralneuropathy.
Vitamin B9
Megaloblastic anemia and Deficiency during pregnancy is
associated with birth defects, such as neural tube defects
Vitamin B12 Megaloblastic anemia
Vitamin C Scurvy
Deficiency diseases
Vitamin A Night blindness, Hyperkeratosis, and Keratomalacia
Vitamin D Rickets and Osteomalacia
Vitamin E
Deficiency is very rare; sterility in males and abortions in females, mild
hemolytic anemia in newborn infants.
Vitamin K Bleeding diathesis
