Vitamin

Site of absorption/Sources

Function

Signs of Deficiency

Signs of Overdose

Vitamin A

Small intestine

Normal Growth and Development

Thickened bone, loss of lung elasticity

Toxic in large amounts

Liver, Kidney, milk fat, Fortified Margarine

Maintenance of epithelial tissue

Epithelial keratinization, Impaired hearing

Transient hydrocephalus, Precocious skeletal growth

Yellow and dark green leafy vegetables

Night Vision

Dryness of cornea, Conjunctiva, Night Blindness, Bitot’s spots

Irritability, Fatigue, Increased intracranial pressure

Orange fruit

Helps provide for normal bone development and tooth formation

Keritinization of salivary glands

Anorexia, Vomiting, Dry and pruritic skin, Loss of body hair, Nystagmus, Gingivitis, Fissures on tongue

Is an antioxidant

Urinary calculi

Hepatosplenomegaly, Lymph node enlargement, Slow clotting time, Increased serum alkaline phosphatase

Vitamin D

Mainly in jejunum

Essential for normal growth and development

Skeletal deformities- fractures, Osteoporosis, Osteomalacia, Osteodystrophy, Rickets

Toxic in large amounts, Muscle weakness, Joint pain, Premature closure of sutures.

Sunlight, Fortified milk, liver, egg yolk, salmon, tuna, and sardines.

Important for the formation of normal bones and teeth

Muscle weakness and loss of tone, Hypocalcaemic tetany, Delayed dentition, Aminoaciduria

Anorexia, Vomiting, Thirst, Polyuria. Fatigue, Lassitude, Headaches

Influences absorption of and metabolism of phosphorus and calcium

Decreased calcium and phosphorus. Increased alkaline phosphatase

Abnormal ECG, shortened QT interval Increased calcium and phosphorus. Decreased magnesium and increased cholesterol.

Vitamin E

Intestine

Is an antioxidant

Increased creatinuria

Possible high blood pressure

Wheat Germ, Vegetable oils, green leafy vegetables,

Protects red blood cells from haemolysis

Increased haemolysis of red blood cells, Muscle weakness

Increased phosphorus.

Egg yolk, nuts

Role in epithelial tissue maintenance

Decreased serum lipid levels

Milk fat

Role is Prostaglandin (hormone) synthesis

Steatorrhea

Vitamin K

Upper Intestine

Blood Clotting

Cutaneous purpura, Ecchymosis

Transient hyperprothrombinaemia

Produced naturally by intestinal flora

Hemorrhage, GIT bleeding, Epistaxis,

Synthetic Vitamin K excess: Haemorrhage, Kernicterus, Vomiting, Porphyrinuria, Albuminuria, Prolonged clotting time.

Liver, soybean oil

Haematuria

Green leafy vegetables, wheat bran

Post-operative hemorrhage

Thiamin (Vitamin B1)

Proximal and lower duodenum, jejunum

Helps in the digestion of carbohydrates

Central nervous system dysfunction

Allergies, Oedema, Fatty Liver, Herpes, Nervousness

Pork, Liver, organ meats, legumes, whole-grains, wheat germ, potatoes.

Essential for growth, normal appetite, digestion and healthy nerves.

Peripheral neuritis

Sweating, Tachycardia Tremors

Made in intestinal tract

Vomiting, Diarrhoea

Vascular hypotension.

Riboflavin (vitamin B2)

Proximal small intestine

Essential for growth

Eyes: Burning, dim vision, photophobia

Essentially non-toxic.

Milk and Dairy, organ meats, green leafy vegetables

Is an enzyme in the body which helps tissues to respire.

Skin: angular stomatitis, chelosis, sebhorrheic dermatitis

eggs

Co-enzyme forms FAD and FMN

Mouth, Magenta tongue

Niacin

Intestine

Acts in metabolism of Carbohydrates and amino acids

Achlorhydria, Dermatitis,

Low Blood Pressure, Burning, Itching skin, Fatty liver

Fish, liver, meat, poultry, many grains, eggs, peanuts,

Involved in glycolysis, fat synthesis, and tissue respiration

Loss of memory, Pigmentation

Peripheral vasodilation, Decreased serum cholesterol, Stimulated central nervous system

Milk, legumes.

Diarrhoea

Increased cerebral blood flow

Made by intestinal bacteria

Retarded growth

Increased pulse rate, Increased respiratory rate

Pyridoxine (vitamin B6)

Upper Small intestine

Aids in synthesis and break down of amino acids

Anaemia

Limited toxicity

Pork, glandular meats, cereal bran and germ, milk, egg yolk,

Aids in Synthesis of unsaturated Fatty acids from essential fatty acids

Cutaneous

Oatmeal, legumes

Essential in conversion of tryptophan to niacin

Peripheral neuritis

Made by intestinal bacteria

Essential for normal growth

Folate

Jejunum, Small intestine

Essential for biosynthesis of nucleic acids

Megaloblastic anaemia, Central nervous system changes

No Toxicity reported

Green leafy veg, organ meats, lean beef

Essential for normal maturation of red blood cells

Glottises, Hepatomegaly, Hyperpigmentation,

Wheat, eggs, fish , dry beans, lentils, asparagus

Coenzyme: Tetrahydrofolic acid

Leukopenia, Sprue,

Broccoli, yeast

Intestinal disturbances

Made in the intestinal tract

Thrombocytopenia

Vitamin B12

Terminal ileum

Involved in the metabolism of single-carbon fragments

Megaloblastic/Pernicious Anaemia, Gastrointestinal tract changes, Leukopenia, Nerve Damage, Peripheral neuropathy

Polycythemia

Animal products, milk, eggs only

Essential for biosynthesis of nucleic acids and nucleoproteins.

Diminished sense of position and vibration, Poor growth, Sore, smooth tongue,

Role in metabolism of nervous tissue

Splenomegaly.

Involved with folate metabolism.

Thrombocytopenia.

Related to growth

Pantothenic acid

Intestine

Essential in the intermediary metabolism of carbohydrate, fat and protein

Cardiovascular changes, Depression, Digestive disorders, Greater susceptibility to infection, Neuromotor disturbances

Essentially non-toxic

Present in all plant and animal foods, The best sources are kidney, liver, salmon and yeast

As part of coenzyme A, functions in the synthesis and breakdown of many vital body compounds.

Physical weakness

Biotin

Upper Small Intestine

Essential component of enzymes

Anorexia

Essentially non-toxic

Liver, mushrooms, peanuts, yeast, milk, meat, egg yolk, vegetables

Involved in synthesis and breakdown of fatty acids and amino acids.

Dermatitis: Fine, non-pruritic, scalp, cheeks, neck, groin and gluteal region.

Banana, grapefruit, tomato, watermelon, strawberries

Anaemia

Made in the intestinal tract

Vitamin C

Proximal ileum, Small intestine

Maintains intracellular cement substance with preservation of capillary integrity.

Poor wound healing,

Excesses do not produce a hypervitaminosis, but they are linked to oxalate stones and gout in susceptible people.

Citrus fruit, tomato, melon, peppers, greens, raw cabbage,

Cosubstrate in hydroxylations requiring molecular oxygen

Scurvy

Guava , strawberries, pineapple, potato

Important in the immune responses, wound healing, and allergic reactions.

Increases absorption of iron

Antioxidant

Mineral

Site of absorption/Sources

Function

Signs of Deficiency

Signs of Overdose

Calcium

Mainly absorbed in the duodenum and jejunum

Builds and maintains bones and teeth

Osteoporosis (brittle bones)

Bitter Taste, Lethargy, inability to sleep[, coma, anorexia,

Milk, yoghurt, cheese, sardines, pilchards with bones

Effects transport functions of cell membranes- acts as membrane stabilizer

Constipation, subcutaneous fat necrosis, Renal calcification Kidney stones.

Oysters, tofu

Influences transmission of ions across cell membranes, the release of neurotransmitters at synaptic junctions, the function of protein hormones, and the release or activation of intracellular and extracellular enzymes.

Tetany, Hypertension

Required in nerve transmission and regulation of heart beat

The proper balance of Calcium, Sodium Potassium and Magnesium maintains muscle tone and controls nerve irritability.

Ionized Calcium initiates the formation of a blood clot by stimulating the release of thromboplastin from the blood platelets.

Necessary Co-factor in the conversion of prothrombin to thrombin, which aids in the polymerization of fibrinogen to fibrin

Phosphorus

Small Intestine

Structural role in bones and teeth

Not Common

Hypocalcaemia (with possible resulting tetany)

Cheese, Egg yolk, milk, meat, fish, poultry, whole-grain cereals, legumes, nuts.

Essential component of nucleic acids and phospholipids are key components in the structure of cell membranes.

Neuromuscular, skeletal, haematological and renal abnormalities occur due to decreased ATP

Energy – phosphorylation of glucose, ATP

Magnesium

Entire length of small intestine

Normal constituent of bone

Anorexia, Growth failure, Cardiac Changes

Laxative effect, Diarrhoea, Transient hypocalcaemia,

Whole Grains cereals, tofu nuts, meat, milk, green vegetables, legumes, chocolate

The proper balance of calcium, sodium potassium and magnesium maintains muscle tone and controls nerve irritability.

Neuromuscular changes e.g.

Muscle weakness, irritability and mental derangement.

Respiratory paralysis

In normal muscle contraction calcium acts as a stimulator, and magnesium as a relaxor

Cardiac arrest

Sodium, chloride, potassium

Absorbed in the intestine

Volume regulation – Na/K/CA ATPase

Not Common

High Blood Pressure

Table Salt

Glucose transport

Seafood, milk, milk eggs

Transport of some amino acids incl. Alanine, Proline, Tyrosine and Tryptophan

Hypokalaemia – lethargy, muscle weakness

Potassium is found in fruit

Sulfur

Needed for synthesis of essential metabolites

Not common

Protein foods such as meat, fish, poultry, eggs, milk, cheese legumes and nuts.

Functions in oxidation/reduction reactions

Mineral

Site of absorption/Sources

Function

Signs of Deficiency

Signs of Overdose

Iron

Duodenum and jejunum

Involved in transport of Oxygen and Carbon Dioxide around the body through heme in red blood cells

Anaemia - lethargy

Nausea, Vomiting, Metallic Taste, Peripheral vascular collapse, Discoloured (black) stools

Liver, Meat, Egg yolk, legumes, whole grains, dark green vegetables, shrimp, oysters

Involved in the Immune System

Anaphylaxis (to iron dextrin’s) Hemosiderosis, Splenomegaly, Negative chromium balance

Involved in cognitive performance

Increased susceptibility to intracellular inflections

Zinc

Absorption occurs through the intestine, and the zinc is then absorbed in the liver

Participates in reactions involving either synthesis or degradation of major metabolites such as carbohydrates, lipids, proteins and nucleic acids.

Short Stature, hypogonadism,

Nausea, Vomiting, Metallic taste, Epigastric distress, Gastric erosion, Sweating, Dizziness, Tachycardia, Hyperamylasemia, T cell dysfunction, elevated LDL/HDL ratio in serum lipid pattern.

Oysters, shellfish, herring, liver, legumes, milk, wheat bran

Stabilization of protein and nucleic acid structure and the integrity of subcellular organelles.

Mild anaemia, Decreased taste acuity

Involved in transport processes, immune function and the expression of genetic information

Delayed wound healing, Hair loss, Skin lesions, Night blindness has also been reported.

Copper

Absorbed to a small extent in the stomach. Most absorption occurs in the jejunum

Used in enzymes- specifically oxidation of iron.

Decrease in serum levels leads to a failure to absorb iron. This leads to Microcytic haemochromic anaemia.

Nausea, Vomiting, Gastrointestinal hemorrhage, Hemolytic anaemia, Jaundice, Chronic hepatic cirrhosis

Liver, shellfish, whole grains, cherries, legumes, kidneys, poultry, oysters, chocolate, nuts

Enzymes have role in mitochondrial energy production, protection from oxidants, and synthesis of melanine and cathecholamines.

Neutropenia, Leukopenia and bone demineralization follows with haemorrhages and skin depigmentation, Defective elastin formation. Failure of erythropeoisis as well as cerebral and cerebellar degeneration lead to death.

Acute hepatic necrosis.

Iodine

Stored in thyroid

Thyroid hormones

Goiter (enlargement of thyroid)

Iodized table salt, seafoods, seaweed, liquorice

Controls reactions involving cellular energy

Cretinism in children born from Iodine deficient mothers

Manganese

Mode of absorption is unknown

Component of enzymes

Infertility

Schizophrenia-like psychotic disorders

Blueberries, whole grains, nuts, legumes, fruit, tea

Associated with the formation of connective and bony tissues, growth and reproduction, and carbohydrate and lipid metabolism.

Parkinson’s disease like neurological disorder.

Fluoride

Hardens teeth and bones?

Not Common

Mottling of teeth

Drinking water, tea, coffee, rice, soyabeans, spinach, gelatin, onions, lettuce

Molybdenum

Legumes, dark green leafy vegetables, cereal grains, organs

Constituent of enzyme xanthine oxidase- used in oxidation-reduction reactions

Hypercupuria, Genu Valgum (in India)

Cobalt

Absorbed through the intestine.

Constituent of vitamin B12

Not common

Increased blood volume, Increase in red blood cells

Liver, kidney, oysters, clams, poultry, milk

Essential in normal functioning of all cells particularly cells of bone marrow, nervous system, and gastrointestinal system.

Selenium

Absorbed in upper segment of small intestine.

Antioxidant

Rare in humans

Peripheral vascular collapse. Weakened fingernails and toenails

Grains, onions, meats, milk, vegetables- depends on Selenium content of the soil

Fat metabolism

Dental enamel defects, Hair loss, Dermatitis, Generalized tremor, and garlicky odour of breath.

Chromium

Normal lipid and carbohydrate metabolism.

Altered carbohydrate metabolism e.g. Impaired glucose tolerance, glycosuria, fasting hyperglycaemia

Nausea and vomiting Increased insulin sensitivity and hypoglycaemia

Corn Oil, clams, whole-grain cereals, meats

Appears to be involved in the function of insulin

Elevated serum insulin levels, and decreased insulin binding