This document discusses vitamins, including their definitions, classifications, sources, functions, deficiencies, and antagonists. It notes that vitamins are organic compounds required in small amounts to perform specific biological functions. They are classified as either fat-soluble (A, D, E, K) or water-soluble (B-complex, C). Most vitamins must be obtained through diet as the body cannot synthesize them. Deficiencies can occur if vitamins are missing from the diet or not absorbed properly. The document also examines provitamins, hypervitaminosis, avitaminosis, and antivitamins.

1. Ritesh Srivastava
DEPARTMENT OF BIOCHEMISTRY
Shridev Suman Subharti Medical College
Dehradun

2.  Vitamins are organic compounds required in
the diet in small amount to perform specific
biological functions for normal maintenance
of the organism. [Reproduction in human
being]
 Required Small amount since their degradation
is relatively slow.
 Naturally occur in food.
 Deficiency occurs when the vitamin is missing
from diet.

3.  Hopkins coined the term “Accessary Factors”
to the unknown and essential nutrients present
in the natural foods.
 In 1912 Hopkins & Funk isolated an active
principle ( an amine) from rice polishings &
later in yeast, which could we Beri-Beri in
pigeons he coined the term Vitamin.

4.  (Vita- Life) he believe that all of term are amines . But
later he realized that only few of them are amines. The
term vitamin however is continued without the final
latter ‘e’.

5. VITAMINS
Fat soluble Water Soluble
Vitamin A
Vitamin D Non B-complex B Complex
Vitamin E
Vitamin K Vitamin C(Ascorbic acid)
Energy Releasing Hematopoietic

6. B Complex
Energy Relesing Hematopoietic
Thiamine [B1] Folic Acid[B9]
Riboflavin [B2]
Niacin [B3] Vitamin B12
Pyridoxine [B6] [Cyanocobalamin]
Biotin [B7]
Pantothanic Acid [B5]

7.  Choline
 Lipoic Acid
 Inosital
 PABA (Para Amino Benzoic Acid)
[To remember- ‘CLIP’]

8. Most of Vitamins are not biosynthesized by the body & hence for
its functional use we have to depend on the diet intake.
Few vitamins which are synthesized & supplement for the use are:
Vitamin D from cholesterol
Vitamin B3 Niacin – from tryptophan
Vitamin K,
Vitamin B7, Are synthesized by
Vitamin B12 normal bacterial flora of gut & intestine,
acting on
Food supplement absorbed
use for body function

9.  Vitamins are widely distributed in nature.
 Foods of plant and animal origin contains rich amount of
various vitamins.
 Usually fat soluble vitamins are associated with fats &
predominantly obtained by fatty diet of plant & animal
origin – fish oils, liver, meat, wheat germ oil etc.
 Water soluble vitamins are predominantly presents in fresh
fruits, vegetables, cereals, grains, yeast etc.

10.  Thus a mixed type of diet. will provide sufficiently for
all type of vitamins to the body, whose function will
maintain normal health, growth and reproduction.

11. It is a condition, due to excessive accumulation of vitamins
in body tissues like liver, spleen, brain and bones.
The manifestation of hyper vitaminosis are due to its toxic
effects on the functional activity of tissues.
Fat soluble vitamins:
Over consumption of these vitamins may increase the
storage capacity and affects the normal functions of the
tissues.
Excessive intake of water soluble vitamins. Does not lead to
hyper vitaminosis, since they are not stored in the body and
any excess intake then daily excreted through urine.

12.  Avitaminosis is a condition produced due to deficiency of
vitamins in the body.
 Absence of vitamins affects the body and make it suffer
from the manifestations.
Causes for Avitaminosis (Vitamin deficiency)
Body can suffer form Avitaminosis due to different reasons:
i) Inadequate dietary intake of vitamins.
ii) Inadequate absorption from GIT lumen due to GIT
disorders.
iii) Inadequate utilization of vitamins.
iv) Drug induced deficiency.

13. Provitamins are precursors of active form of vitamins,
they are present in food substances, when ingested in the
body, by the help of enzymatic action they are
immediately converted to vitamin.
As such provitamins have no function similar vitamin
form.
Examples: Corrotenes (yellow pigments) present in
fruits & vegetables are provitamins of vitamin A

14. I – Carrotene [Most Potent]
In Intestinal mucosal cell β-carrotene Dioxygenase
2 milecules of Retinal [Vitamin A]
II – 7-Dehydrocholesterol – Precursor of VitaminD
[Provitamin]
7-Dehydrocholesterol
Skin U.V Light
Cholecalciferol [Vit D3]

15.  These are chemical compounds which inhibit or oppose
the vitamin activity and produce vitamin deficiency.
 They are also termed as Antagonist and their action as
Antagonism.
 Mostly related to Vitamin B complex members and
Vit. K.
 Vitamins B-complex members form coenzymes and
mediate enzyme reactions.
 Antivitamin are generally structural analogs of these
vitamins hence they participate in enzymatic reactions
and competitively in habit the reactions as they are not
specific in action.

16. I – Dicumarol Warfarin. Vitamin K.
II – Avidin. Biotin.
III – Oxythiamine . Thiamine.
IV – Favin Monosulphate. Riboflavin.
V – Methotrexate. Folate.

17. All vitamins are potent growth factors which maintains normal
health growth and reproduction.
I – Vitamin A :- Role in vision growth & differentiation of epithial
cells.
II – Vitamin D :- Role in mineral (calcium) metabolism bone
mineralization.
III – Vitamin E :- Antioxidant activity – protects tissues.
IV – Vitamin K :-Role in blood clotting mechanism
V – Vitamin C :- Reducing agent.
VI – Vitamin B complex :- They form co-enzymes [organic factor]
which mediate [help] certain enzyme reactions of metabolism.