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By R e m y a.. P. R2 0 16 -2 4 -0 0 1P h D. C o m m u n it y S c ie n c e C o l l e g e o f H o r t ic u l t u r e K A U , V e l l a n i k k a r a
FAT SOLUBLE VITAMINS
WHAT ARE FAT SOLUBLE VITAMINS ?• THEY DISSOLVE WITHIN THE BODY’S FAT CELLS• USUALLY FOUND IN FAT AND FATTY FOODS.• CAN BE USED IMMEDIATELY OR STORED IN LIVER AND
FATT CELLS FOR FUTURE USE• BILE SALTS ARE ESSENTIAL FOR THEIR ABSORPTION• THEY ARE NOT EXCRETED THROUGH URINE• THE 4 FAT SOLUBLE VITAMINS ARE A,D,E AND K.
• The word vitamin comes from the Latin word “vita” means life• Vitamins are chemicals found in very small quantity in
different foods• They have been defined as organic compounds
required in in minute amounts to maintain normal health of organisms.
VITAMIN - A• Widely distributed in animal and plant foods• Animals- pre formed-Retinol• Plants –pro formed - Carotene
Beta Carotene• It is cleaved in the intestine to produce two moles of
Retinal.
• In humans this conversion is insufficient , hence beta carotene possesses about one sixth activity of vitamin A compared to that of retinol.
FUNCTIONS
• Retinal is a necessary structural component of Rhodopsin, the light sensitive pigment within the rod and cone cells of the retina.• Rods are involved in dim light vision• Cones are responsible for bright light and colour
vision.
vision
Colour vision
• the colour vision is governed by colour sensitive pigments porphyropsin(red), iodopsin (green) and cyanopsin (blue).• All these are retinalopsin complexes.• When bright light strikes the retina,one or more of
these pigments are bleached depending on the particular colour of the light.• These pigments dissociates into retinal ad opsin.• This reaction passes on a nerve impulse to brain.
Epithelial cell integrity
• Many epithelial cell appear to require vitamin A for proper differentiation and maintenance.• Lack of this vitamin leads to dysfunction of many
epithelia• The skin becomes keratinized and scaly and mucus
secretion is suppressed.
Bone remodelling Reproduction • Normal level of vitamin A
is needed for sperm production.• Normal reproductive
cycles in females require adequate availability of vitamin A.
• Normal functioning of osteoblast and osteoclasts is depent upon vitaminA
Resistance to infection
• The deficiency of Vit.A has been shown to increase the frequency and severity of diseases.• Studies shows a dramatic decline in mortality from
diseases such as measles by the simple and inexpensive administration of vitamin A .
Signs of deficiencyoccular Extra occular
• Retarded growth• Skin disorders• Effect on reproductive
organs• Effect on bone
• Night blindness• Conjuctival xerosis• Bitot’s spot• Corneal xerosis• keratomalacia
Night blindness
Conjuctival xerosis
Bitot’s spot
Corneal xerosis
keratomalacia
VITAMIN -D• Also called sunshine vitamin• Available in 2 forms • D3 chle calciferol• D2 ergocalciferol
• Cholecalciferol (D3) : it is made in the skin of animals and humans• Ergocalciferol : obtained artificially by irradiation of
ergosterol
Chemical origins of vitamin D• Precurors are found in both animal tissue and yeast.• In yeast ergosterol is converted to Vit D2 –
ergocalciferol.• In the dermal cells of animals, the precursor 7-
dehydroxycholesterol is first converted to a previtamin D3 then to vitamin D3.• Vit D2 and D3 are both converted to similar active
compounds in the liver and kidney.
Functions • Calcium balance • Cell differentiation• Immunity• Blood pressure regulation• Development of bones and teeth.
Endocrine paracrine &intracrine functions of vitD
Deficiency • Rickets – in children• Osteomalacia – in adults• Increased risk of osteoporosis
Rickets • Rickets is the softening and weakening of bones in children, usually
because of an extreme and prolonged vitamin D deficiency.• Vitamin D promotes the absorption of calcium and phosphorus from
the gastrointestinal tract. A deficiency of vitamin D makes it difficult to maintain proper calcium and phosphorus levels in bones, which can cause rickets.• If a vitamin D or calcium deficiency causes rickets, adding vitamin
D or calcium to the diet generally corrects any resulting bone problems for your child. Some skeletal deformities caused by rickets may need corrective surgery.
Osteomalacia • The term "osteomalacia" is often restricted to the
milder, adult form of the disease. Signs and symptoms can include diffuse body pains, muscle weakness, and fragility of the bones.
Signs and symptoms• Diffuse joint and bone pain (especially of spine, pelvis, and
legs)• Muscle weakness• Difficulty walking, often with waddling gait• Hypocalcemia • Compressed vertebrae and diminished stature• Pelvic flattening• Weak, soft bones• Easy fracturing• Bending of bones
Oral manifestation• Teeth developmental abnormalities of dentine and
enamel.• Higher risk of caries• Enamel – there may be hypoplasia, may be molted
yellow or grey in colour
VITAMIN E
Also called anti aging factor.Tocopherol from the word toco means childbirth and pheros means to bear.
sources
Functions • Vitamin E is an antioxidant. This means it protects
body tissue from damage caused by substances called free radicals, which can harm cells, tissues, and organs. They are believed to play a role in certain conditions related to aging.• The body also needs vitamin E to help keep the
immune system strong against viruses and bacteria.
• Vitamin E is also important in the formation of red blood cells and it helps the body use vitamin K. It also helps widen blood vessels and keep blood from clotting inside them.• Cells use vitamin E to interact with each other and
carry out many important functions.• Whether vitamin E can prevent cancer, heart disease,
dementia, liver disease, and stroke
Deficiency • Reproductive : abortion in females; atrophy of
spermatogenesis in males and leading to permanent sterility.• Heart : necrosis and fibrosis of heart muscles• Blood capillaries : leads to degenerative changes
VITAMIN K
• Phyloquinone is essential for reproduction & other factors involved in blood clotting mechanism• Known as anti hemorrhagic vitamin
Sources
Functions
Deficency • Easily bruise or bleed.• Cartilage calcification.• Uncontrollable bleeding at surgical or puncture sites.• Brain bleeding in newborns.
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