Vitamins are the organic substances in food,
which are required in very small amounts and
are not synthesized by the body.
They occur naturally in food and are essential
for good health.
Vitamins are broadly categorized into two
Fat soluble vitamins –Vitamin A,D,E and K
Water soluble –Vitamin B complex and
Liver is the richest source,fish,eggs
Green leafy vegetables, carrots, and yellow fruits
Plays an important role in vision. Retinaldehyde is the part of
the photoreceptors of rods in retina
Vitamin A is also necessary for normal growth, fetal
development, fertility, haemopoiesis and immune function
Corneal ulceration and necrosis
Keratomalacia with scarring leading to blindness
Deficiency is treated by a single large dose of
retinol as palmitate or acetate 200000 IU orally or
Xerophthalmia – 60mg of vit A in oily soln
TOXICITY of vitamin A causes liver
damage,hyperostosis and teratogenicity.
Acute overdose can cause nausea and headache,
raised intracranial pressure and skin
Excessive intake of carotene causes
hypercarotenosis (pigmentation of skin)
Natural form ofVitamin D is cholecalciferaol.
It is formed in the skin by the action of
ultraviolet rays on 7-dehydrocholesterol.
Dietary sources are egg yolk , fish oil, butter
Cholecalciferol is not biologically active. It is
converted in the liver to 25-
hydroxycholecalciferol which is further
hydroxylated in kidneys to 1,25
dihydroxycholecalciferol.This is the active
form of vitamin D
Vitamin D helps in uptake of calcium from the
gut and bone formation
Maintains normal functioning of muscles,
immune function and inflammation.
DEFICIENCY leads to poor bone
mineralization causing rickets in children and
osteomalacia in adults.
Deficiency occurs due to malabsorption or
chronic renal disease
TOXICITY leads to hypercalcaemia leading to
α- tocopherol is the active form of vitamin E
in human body.
• The main function of vitamin E is anti oxidant. It
intercepts free radicals & prevents destruction of cell
• It prevents the oxidation of PUFA by free radicles.
• It is involved in anti-inflammatoy and immune
• It inhibits platelets aggregation.
• It enhances vasodilatation.
Vitamin E deficiency
•Severe vitamin E deficiency causes:
Neurological symptoms (impaired coordination)
& muscle weakness causing ataxia.
Increased risk of cardiovascular diseases
Deficiency occurs in severe PEM and fat
Deficiency is t/t by 800-1200mg of tocopherol/d
Prevention of cardiovascular diseases
Excess vitamin E may cause:
Impaired blood clotting leading to increased
risk of bleeding in some persons.
It is recommended that vitamin E supplements
to be stopped one month before elective
The K is derived from the German word
There are 2 naturally occurring forms of vitamin
K. Plants synthesize phylloquinone (vitamin K1) &
bacteria synthesize menaquinone-3 (vit K2).
•Vitamin K is needed for production of
vitamin K-dependent coagulation factors in
•Other functions include:
Assist in bone mineralization. The
mineral binding capacity of osteocalcin
requires vit K.
SOURCES OFVITAMIN K
Bacteria in large intestine produce vit K2
and supply 40-50% of human requirement.
Almonds & peanuts
Avocado & Broccoli
Vitamin K deficiency
deficiency leads to delayed coagulation and
Is uncommon in adults. Only those with severe
liver disease (obst. Jaundice) chr. Small intn dis &
those on oral anticoagulants are at risk.
Exclusively breast fed & premature babies are at
risk coz human milk is low in vitamin K.
Hemorrhagic disease of the newborn is a serious
threat to life & routine vit k prophylaxis is
Humans, unlike other mammals, are unable to
make ascorbic acid & they get it from food.
Rich dietary sources are citrus juices (orange,
grapefruit & lime), strawberry, Guava, tomato,
sweet red pepper & broccoli.
Recommended daily intake is between
15-120 mg/day depending on age. Smokers &
lactating mother needs the higher range.
promotes absorption of non-heme iron
Connective tissue metabolism
Vitamin C deficiency
Severe deficiency leads to Scurvy with the
Bleeding & bruising easily- swollen bleeding
gums, petechial h’ges,ecchymosis
Joint pain & swelling
Poor wound healing
Fatigue & lack of concentration
• Cardiovascular diseases
• Diabetes Mellitus
• Cancer prevention
• Common cold
Treatment -250 mg vit C 8hrly
Thiamine (Vit. B1)
Known as B1 cause first identified.
Function – important role in peripheral nerve
Food sources– pork, meat, yeast, beef,
legumes, whole grains, nuts.
Deficiency – poor intake, chronic illness,
chronic alcoholism, hyperemesis, bariatric
Signs and symptoms – anorexia, irritability
and Beri Beri
Types of Beri Beri --- wet, dry and infantile
Wet type – Cardiovascular symptoms,
Cardiomegaly, tachycardia, CCF
Dry type – symmetrical peripheral neuropathy
In alcoholics – chronic deficiency causes CNS
manifestations like horizontal nystagmus,
ophthalmoplegia, cerebellar ataxia, mental
impairment known as Wernicke’s
Wernicke’s Encephalopathy with loss of memory
and psychosis is known as Wernicke’s
TREATMENT– acute deficiency
100 mg/day IM for 7 days f/b 10 mg/day till
Riboflavin (Vit. B2)
Important for metabolism of CHO,fat,proteins
Deficiency causes-- Lesions of mucocutaneous
surface of oral cavity and skin, Corneal
vascularization, Anemia and Personality changes
Sources are-- Milk and dairy products, Enriched
breads, Cereals, Fish, Eggs, Broccoli and Legumes
Toxicity– not known becoz GI absorption is very
Niacin (Vit. B3)
Refers to nicotinic acid nicotinamide and
derivatives.They are precursors of NAD and
NADP which are important in oxidation and
reduction reactions in the body.
Sources—beans, milk, meat, eggs
Deficiency causes Pellagra
Common in corn eating
population, alcoholics Hartnup’s
disease, carcinoid syndrome
S/S of Pellagra
Loss of appetite, gen weakness, irritability
abdominal pain and vomiting
Characteristic skin rash, pigmented and
scaling skin(rash known as Casal’s necklace)
Severe Pellagra--3Ds leading to death
dermatitis diarrhea dementia
Treatment – 100 -200 mg of nicotinamide
TDS daily for 5 days
Pantothenic Acid (Vit. B5)
Component of co-enzyme A
Source– liver, yeast, egg yolk, whole grains,
Deficiency—GI disturbances, depression,
muscle cramps paresthesias, ataxia
No toxicity known
Pyridoxine (Vit B6)
It is a cofactor for many enzymes involved in
amino acid metabolism
Synthesis of heme and neurotransmitters
Metabolism of glycogen, lipids, steroids and
Sources– legumes, nuts, wheat bran, meat .
Bioavailability is more in animal sources.
Microcytic hypochromic anemia due to reduced
Hyperhomocystenemia -increased risk of CV
In infants diarrhea ,seizures
Some drugs like INH ,penicillamine ,alpha dopa
RDA--- 1.5-- 2 mg/day
100mg im daily for seizures
Folic Acid (Vitamin B9)
1. Needed for RBC & DNA formation, cell multiplication esp.
2. Newly discovered functions:
a. Prevents neural tube defects
b. Prevents heart disease (reduces homocysteine levels)
c. Prevents colon cancer
Peak incidence 4-7 months
Deficient dietary intake: goat’s milk deficient & powdered
milk poor source
Sources are liver, green leafy veg, and fortified cereals.
Deficient absorption as in celiac
disease, achlorhydria, anticonvulsant
drugs and zinc deficiency
hypothyroidism, drugs like trimethoprim
Increased requirement during rapid
growth & infection
Asso with vitamin B12 deficiency &
Increased destruction possible in
Folic Acid Deficiency
1.Megaloblastic anemia w/ irritability,
failure to gain wt & chronic diarrhea
RDA: 20-50mcg/24 hrs
1.Parenteral folic acid 2-5mg/24 hrs,
response in 72 hrs, therapy for 3-4 wks
2.Transfusions only when anemia severe
Cobalamine (Vitamin B12)
Vitamin B12 is absorbed from the terminal ileum
in presence of intrinsic factor
Deficiency occurs in elderly patients, alcoholics,
malabsorption, drugs like neomycin
Clinical Manifestations of deficiency:
1. Megaloblastic anemia
2. Neurological includes ataxia, paresthesias,
hyporeflexia, Babinski responses, clonus &
3. Tongue smooth, red & painful
RDA: Infants 0.5 mcg/day
Older children & adults 3mcg/day
1. Prompt hematological response w/
parenteral vitamin B12 1-5mcg/24hrs
2. If there is neurological involvement
1mg IM daily for at least 2wks
3. Pernicious Anemia: Monthly vitamin
B12 1mg IM necessary throughout
Dietary sources – milk ,cheese, yoghurt, eggs,
fish, almonds, peanuts, peas and beans
Calcium absorption is impaired in vit. D
deficiency, malabsorption and some foods
Deficiency causes impaired bone
mineralization in children and increased bone
loss in adults
Dietary deficiency is rare
Phosphates are added to processed foods
Deficiency occurs in premature infants, renal
tubular phosphate loss.
Deficiency causes hypophosphatemia and
Needed in formation of Hb, and involved in
many enzymatic reactions.
Dietary sources are red meat, liver, fish,
shellfish,oatmeal, legumes, nuts, dried fruits
Normal daily loss is 1 mg by desquamated
surface cells and intestinal loss.
30 mg of iron is lost in menstruation
Daily intake of 8 mg
Vitamin C enhances iron absorption
Overload of iron leads to haemochromatosis and
Sources are sea fish, seaweed and plants
grown near the sea.
Deficient in mountainous regions.
Deficiency cause IDD, goitre is common,
congenital hypothyroidism, deafness, poor
reflexes and poor learning
Present in meat, shellfish, nuts and legumes
Zn helps in synth and stabilization of protiens
Deficiency is seen in PEM, malabsorption
syndromes, alcoholics and alcoholic liver disease.
Deficiency is characterized by growth
retardation, hair loss, chronic diarrhea ,muscle
wasting and, mental apathy.
Zn promotes general well being, healing of skin
lesions and improves appetite
Prevents free radical damage to the cells.
Takes part in conversion of thyroxin to
triiodothyronine in liver
Deficiency – hypothyroidism,
cardiomyopathy in children and myopathy in
Prevents dental caries.
Deficiency is seen where people consume soft
Excess fluoride cause increase bone
density, calcification of ligaments and
tendons, also affects the dental enamel and
causes mottling, pitting and pigmentation.
DEFICIENCY can cause microcytic
hypochromic anemia, neutropenia, retarded
growth in children, skeletal rarefaction and
Abnormal copper metabolism is seen in
Deficiency occurs in PEM or prolonged