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413 PHG
50% by Dr.Ebtesam S. Al-Sheddi -15 marks midterm exam-20 marks final exam
50% by Dr. Areej Al-Taweel-15 marks midterm exam--20 marks final exam
-Lab :-30 marks: - Practical exam
COURSE DESCRIPTION The course will cover the following subjects:
Vitamins Minerals Allergens Biologics
BY THE END OF THE COURSE
You should be able to know: What are the Water soluble vitamins What are the Fat soluble vitamins The recommended dose, function,
deficiency and the toxicity of each vitamin.
What are the micro and macro-minerals
The recommended dose, function, deficiency and the toxicity of each mineral.
What are allergens and the different types.
What are biologics and the different types
Vitaminslecture 1
Presented By :Ebtesam Al-Sheddi
VITAMINS An organic compound required as a nutrient
in tiny amounts by an organisms. It cannot be synthesized in sufficient
quantities by an organism, and must be obtained from the diet.
13 VITAMINS FOR GOOD HEALTH: 2 GROUPS
Water soluble vitaminsB group:B1 thiaminB2 riboflavinB3 niacin B5 pantothenic acidB6 pyridoxineB7 bitoinB9 folic acidB 12 cyanocobalminVitamin C ascorbic acid
Fat soluble vitaminsVitamin AVitamin DVitamin EVitamin K
FAT VERSUS WATER SOLUBLEVITAMINSFat-soluble
vitamins Dissolve in fat Require bile
acids to be dissolved and then absorbed.
enter the lymph, then the blood
Can be stored in body: liver, adipose tissue.
Toxicity is possible.
Water-soluble vitamins
Dissolve in water. Easily absorbed. Not stored in large
quantities. Execrated via
urine. Generally non-
toxic.
Fat soluble vitaminsvitamin A
Generally called retinol.
It is a group of compounds with the biological activity of retinol.
These compounds include:
Provitamin A and Preformed vitamin A
Preformed vitamin A Provitamin A Animal source Called retinoids: Retinol (key player)
and retinyl ester (retinylpalmitates).
Consist of 4 isoprene units (C20)
Plant source Called carotenoids: α-carotene, β-
carotene and β-cryptoxanthin.
Consist of 8 isoprene units (C40)
Retinoids and carotenoids are precursors for the biosynthesis of 2 essential metabolites of vitamin A:
11-cis-retinal and all-trans-retinoic acid.
Vitamin A functions
11 -cis- retinal All trans-retinoic acid
Required for night and color vision.
Formed in retina. Component of visual
pigments (rhodospin rods) that present in retina.
The most bioactive form. Required for:
1. regulation of embryonic development and growth and reproduction.
2. maintenance of epithelial tissue and repair of body tissues.
3. proper function of immune system
Carotenoids
Serve as antioxidants
.
Source: Preformed: liver, milk,
ready eat cereal, margarine and egg.
Provitamin: carrot, cantaloupe, sweet potato and spinach.
Recommended daily allowance (RDA) = 4000 – 5000 IU (International Units).
1 IU from 0.3 µg of retinol or 0.6 µg of β-carotene
Vitamin A deficiency More obvious deficiency symptoms than
other vitamins Night blindness
Leading cause of blindness in third world countries
Cell keratinization Dry skin (treatment and pregnancy?) Xerophthalmia (dryness of cornea &
conjunctiva) Reproductive failure Abnormal skeletal
development/maintenance Immune dysfunction Respiratory infection.
Hypervitaminosis A• Skeletal malformations, spontaneous fractures,
internal hemorrhages• Overconsumption of beta carotene from food sources
may cause skin to turn yellow but is not harmful• Birth defects and miscarriage• Decalcification, joint pain, fragility• Dry itchy skin (caution about acne treatments) • Hair loss• Liver damage
Fat soluble vitaminsvitamin D
The two major forms are vitamin D2 or ergocalciferol, plant
version vitamin D3 or cholecalciferol, animal version
(Calciferol)
Vitamin D2 (made from ergosterol)
Vitamin D3 is made in the skin when 7-dehydrocholesterol reacts with ultraviolet light.
Vitamin D3 is biologically inert, must undergo two hydroxylation reactions to be activated in the body.
Calcitriol (1,25-dihydroxycholecalciferol) is the active form of vitamin D
Vitamin D - Functions
Regulation of bone health, calcium, and phosphorus
Regulation of muscle composition and muscle function
Prevention of cancer Regulation of immune system Regulation of insulin and blood sugar Regulation of blood pressure and
cardiovascular health
Sourses Vitamin D is naturally produced by the human body
when exposed to direct sunlight. Expose hands, face, arms 2-3 x/week for 5-10
minutes each time. Milk, yogurt, margarine, cereals, bread, pastries
fortified with vitamin D2 and/or vitamin D3.
Egg cod liver oil and salmon Adequate Intake (AI) for VitaminD
• 5 ug/d (200 IU/day) for adults under age 51
• 10-15 ug/day (400 - 600 IU/day) for older adults
–May need combination of fortified foods
Vitamin D deficiency
impaired bone mineralization and leads to bone softening diseases, rickets in children and osteomalacia in adults, and possibly contributes to osteoporosis.
Hypervitaminosis D
Hypercalcemia High blood pressure Anorexia, nausea and vomiting These symptoms are often followed by
polyuria, polydepsia, weakness, nervousness, pruritus, and eventually renal failure