This document discusses vitamins and vitamin deficiencies. It defines vitamins as natural micronutrients that have specific biochemical functions and are required in small amounts. Vitamin deficiencies can cause diseases like scurvy from vitamin C deficiency. The document also discusses cases of vitamin deficiency like avitaminosis from long-term deficiency, hypovitaminosis from inadequate intake, and latent hypovitaminosis where symptoms appear under stress. It notes some vitamins can be destroyed by other substances in foods. Too much vitamin intake can also cause hypervitaminosis. Vitamins have medical uses and are sometimes added to foods through processes like vitaminization, revitaminization, and standardization.

1. SIMS 305- Clinical Biochemistry
Dr. Ali Raza
Senior Lecturer
Centre for Human Genetics and Molecular Medicine (CHGMM),
Sindh Institute of Medical Sciences (SIMS), SIUT.

2. Vitamins

3. Introduction of Vitamins

4. Vital Amine
Vitamin

5. Vitamins
• Natural micronutrient organic substances.
• Having specific biochemical functions in the human body
(essential for health maintenance).
Vitamin A helps form and maintain healthy teeth, bones, soft tissue,
mucus membranes, and skin.
Vitamin B12 helps form red blood cells and maintain the central nervous
system.
Vitamin C is an antioxidant that promotes healthy teeth and gums.
helps the body absorb iron and maintain healthy tissue.
promotes wound healing.

6. Vitamins are:
• Required in very tiny (mcgs) and balanced amounts.
• Not made in the body (or not in sufficient quantity)
• Obtained from animals, plants, and microorganisms.
• Their deficiency resulted in a specific diseases.

7. Cases of Vitamin Deficiency and Toxicity
(1). Avitaminosis:
Any disease caused by chronic or long-term vitamin deficiency
or caused by a defect in metabolic conversion, such as
tryptophan to niacin.
It leads to well defined symptoms e.g.
Xerophthalmia due to Vitamin A deficiency.
Rickets due to Vitamin D deficiency.
Pellagra due to Vitamin B3 deficiency.
Beriberi due to Vitamin B1 deficiency.
Scurvy due to Vitamin C deficiency.

8. Cases of Vitamin Deficiency and Toxicity
(2). Hypovitaminosis
• Resulted from inadequate supply of one or more vitamins.
• It appears in the form of well - defined symptoms as
skin changes
reduced vitality and
low resistance to infections.

9. (3). Latent hypovitaminosis:
• A case of unrecognizable deficiency symptoms but
immediately appeared under sudden stress or exposure
to different environment.
• Latent iron deficiency (LID), also called iron-
deficient erythropoiesis,
• medical condition in which there is evidence of iron
deficiency without anemia

10. (4). Hypovitaminosis due to Anti- vitamins:
• Thiaminase in raw fish destroy Vit. B1.
• Avidin in raw egg forming complex with biotin
(vitamin) (biotin – avidin) prevents absorption
of biotin.
• Liatin in linseed oil is antagonist to Vit. B6.

11. 5. Hypervitamninosis:
A case which develops only upon prolonged use
of excessive amount of vitamins.
Hypervitaminosis A
Occurs after large
over dosage of the vitamin.
Symptoms include:
Headache
Abdominal pain
Nausea or vomiting
Lethargy
Visual changes
Impaired consciousness
Hypervitaminosis D
caused by excessive ingestion or
over prescription of prescribed
medications such as calcium with
vit. D.
Symptoms include:
Polyuria
Vomiting
Constipation
Hypertension
Seizures - can be fatal

12. Medicinal applications of Vitamins
Elimination of hypovitaminosis.
Treatment of some diseases.
Prophylaxis against some diseases.

13. Cases of addition of Vitamins to food
1. Vitaminisation:
Addition of vitamins to foods which do not
necessarily contain them naturally
• Addition of vitamins A and D to margarine).
2. Revitaminisation:
Restoration of the original vitamin contents of food that
is lost during processing.
(Flour loss about 70% of its vitamin B content;
Skimmed milk must be revitaminized with
vitamins A and D as they removed on skimming
with fat).

14. Cases of addition of Vitamins to food
3. Standardization:
Compensation of seasonal variations of vitamins in food
(E.g.
• Milk must standardized due to seasonal variation of
vitamin A).

15. 4. Enrichment: Addition of vitamins over the initial
natural level e.g. in Milk and flour.
5. Stabilization of food: Some food products show change
in color and taste due to oxidation by light and air.
Vitamins C and E ( water and fat soluble
antioxidants) are used to protect food from
oxidation and thus saving its nutritional value.
6. Coloring of food products: The carotenoids (natural fat
soluble pigments and pro-vitamin A) and synthetic
carotenoids as: β-carotene, β-apo-8‘- carotenal, and
anthaxanthin are suitable for the coloring of
margarine and cheese.