introduction nutrition

1. Chapter four
Prepared by Nutritionist: fardus fuad rageh

2. Chapter four
Vitamins
Introduction:
• Vitamins are all organic compounds which, as originally
defined, cannot be synthesized in the human body and
must be provided in the diet.
• They are essential for the normal processes of
metabolism, including growth and maintenance of
health.
• It is known that the body is able to produce part or even
all of its requirements for some of the vitamins,
Example: Vitamin D from cholesterol and niacin from
Tryptophan.

3. types of vitamins
there are two types of vitamins
 water soluble vitamin and
 fat soluble vitamin

4. The Water soluble Vitamins
• The Water soluble Vitamins Include the B- Vitamins
and Vitamin C.
• They share few common properties besides their
solubility characteristics.
• Since they are water soluble excess can be excreted
through urine.
Hyper-vitaminosis may not cause toxicity.
Most of these vitamins act as coenzymes.
The B- Vitamins are essential and must be provided
through diet: these include:

5. Continue…………..
-
- Thiamine (Vit B1
- Riboflavin (Vit B2
- Niacin (Nicotinic acid (or
Nicotinamide3)
- Pantothenic acid (Vit B5
- (Pyrodoxine,pyridoxal,&
Pyridoxamine 6)
- Biotin
- Vitamin B12(Cobalamin)
- Folic Acid

6. Thiamine (vitamin B1}
Sources
:
 The good sources of Thamine are:
Seeds,
Nuts,
Wheat,
Legumenious plants (rich source).
 RDA: Minimum requirement 1.0mg for adults, infants and
children 0.4-1.3mg Requirment increases in conditions of
Anoxia-shock, Hemorrhage, injury, illness, fever and
hyperthyroidism. Also increased carbohydrate in take,
pregnancy and lactation.

7. Continue……
 Thiamine deficiency
• Symptoms: There are two types
Dry beri-beri not associated with edema and
 wet beri-beri with edema, probably due to congestive
cardiac failure and low plasma albumin.
• Symptoms
Include Peripheral Neuropathy, and
Anorexia.
The signs may progress to edema and Cardiovascular
disorders, Neurological & muscular degeneration.

8. Riboflavin (Vitamin B2
Source
Meats,
Nuts,
Legumes,
Milk,
fish,
egg etc.
RDA: 1.5-2.5mg for adults, infants 0.6mg, children 1.0-1.8mg
Deficiency
Lack of riboflavin in the diet causes a generally non fatal
syndrome of inflammation of the corner of mouth (angular
stomatitis), painful glossitis of tongue (Purple) and Scaly
dermatitis

9. Continue………..

10. Niacin vitaminB3
:Source
milk,
Lean meat,
grains,
cereals and from Metabolism of Tryptophan.
 RDA: Adults17-21mg, infants 6mg.
 The requirement increases with increased intake of
calories, illness, severe injury ,infection ,burns, high corn
(maize) diet, pregnancy and lactation.
• Deficiency
Deficiency leads to Pellagra, a disease involving GIT and
CNS. The disease is characterized by intense irritation and
inflammation of the mucous membranes of the mouth

11. continue…..
and other parts of the GIT, leading to gastro- intestinal
hemorrhage, Dermatitis, Dementia & Diarrhea. (the “3-
D’s” cardinal features)

12. Vit C (Ascorbic Acid)
Source:
Citrus fruits,
Potato,
tomato & green vegetables
RDA: 60mg/day
Deficiency:
scurvy symptoms are spongy gums and
bleeding of gums due to defective collagen
synthesis.

13. Continue…………….

14. Fat Soluble Vitamins
 fat soluble vitamins are stored in the tissues as they are not
readily absorbed from the food. With the exception of Vit.
K, they do not serve as coenzymes. Indeed Vit D act more
like hormone.
vitamin A
is present in the diet as retinol or as β-carotene some of which
is hydrolyzed in the intestine to form retinol. It is a generic
term for a collection of three forms of Vitamins, retinol, retinal
and retinoic acid (Retinoids) all of which are found from
animal and plant sources.

15. Continue…….
Source:
A rich source is Liver, but leafy vegetables and some fruits provide the
largest amount of βcarotene
Liver, egg yolk, butter and milk are good sources of βcarotene.
Functions
• β-carotene has an antioxidant role and prevents the development of
diseases in which the action of free radicals is implicated .
• It plays a protective role against Cancer and cardiovascular disease.

16. Vit A deficiency
 Vit A affects growth and differentiation of epithelial
cells leading to defective epitheliazation, a condition
affecting the cornea of the eye. It produces softening ,
Severe Vit A deficiency leads to progressive
keratinization of the cornea and possibly permanent
blindnes

17. Vitamin D:
 Vitamin D is the only vitamin that is usually not
required in the diet, for this reason it is rather
classified as a hormone since under conditions
of inadequate exposure to sunlight that dietary
intake is required.

18. Continue…..
Sources:
Fish oils,
milk, egg yolk are naturally rich sources of Vit D.
Functions:
Target organs are bone, Kidney and Intestine. Calcitriol
promotes bone mineralization.

19. Deficient of vitamin D
Type I
vit D dependent rickets Is caused by an inherited defect in
the conversion of 25(OH)- D3to calcitriol
Type II
Is a vitamin D-resistant rickets caused by absence of
calcitriol receptor.
In adults the deficiency produce Osteomalacia due to
decreased absorption of calcium and phosphorous,
maintains a low plasma level resulting in weak
mineralization of bones.

20. ……

21. Vitamin E
Function
The main function of Vit E is as an antioxidant, in particular a
membrane antioxidant associated
with lipid membrane structure.
Source:
The richest source is vegetable oil, and nuts
.

22. Vitamin K
Functions
It is the only one acting as co-enzyme from the group of Fat
soluble vitamins.
This vitamin is also synthesized by intestinal bacteria.
It is required for post translational modifications of several
proteins required in the coagulation cascade. For e.g. Factor II,
VII. IX and X

23. vitamin deficiency
Thiamin B1 beriberi
Riboflavin B2 Angular stomatisis,glostisis
Niacin B3 pellagra
Pantothenic acid B5
Pyridoxamine B6
Bioti B8
Folic Acid B9
Cobalamin B12
V.C (Ascorbic Acid scurvy
V.A Light blindnes,skin,bone,theat
general metabolism
V.E
V.D rickets
V.K bleeding

24. Thank you for your attention
Prepared by nutritionist: fardus fuad rageh