Слайд 2Key terms
Vitamin – organic molecule essential for body processes;
Avitaminosis –
total deficiency of one or more vitamins;
Hypovitaminosis – deficiency of
one or more vitamins;
Hypervitaminosis – excess amount of intake of one or more vitamins.
Слайд 3Vitamins
Vitamins were first discovered in 1890 when the disease beriberi
was found to be due to a lack of vitamin
B
A small amount of vitamins is ingested in food and play important roles in regulation of the metabolism of the body.
The main source of vitamins is plants
However, animal tissues, especially liver, contain a rich supply of vitamins
Слайд 4Vitamins
Overheating of food, therefore, may cause destruction of vitamins
Functions of
vitamins
--to give the body resistance to infection
--to prevent against bleeding
and blood deficiency
--to assist in formation, development and rigidity of bone tissue
--to regulate growth, development and reproduction
--to provide a regular program of nutrition
Слайд 5Polish biochemist Casimir Funk discovered vitamin B1 in 1912 in
rice bran.
He proposed the complex be named "Vitamin" (vital amines).
By
the time it was shown that not all vitamins were amines, the word was already ubiquitous.
Слайд 6Vitamin - definition
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.
Vitamins have diverse biological function:
hormone-like functions as regulators of mineral metabolism (vit. D),
regulators of cell and tissue growth and differentiation (some forms of vit. A)
antioxidants (vit. E, C)
enzyme cofactors (tightly bound to enzyme as a part of prosthetic group, coenzymes)
Слайд 7Vitamin classification
Lipid-soluble vitamins (A, D, E and K)
hydrophobic compounds,
absorbed efficiently with lipids,
transport in the blood in lipoproteins or
attached to specific binding proteins,
more likely to accumulate in the body,
more likely to lead to hypervitaminosis
Слайд 8Vitamin classification
Water-soluble vitamins - 8 B vitamins and vitamin C
Function:
mainly as enzyme cofactors,
hydrophilic compounds dissolve easily in water,
not
readily stored, excreted from the body,
their consistent daily intake is important.
Many types of water-soluble vitamins are synthesized by bacteria.
Слайд 9Metabolic functions of vitamin A
Vision
Gene transcription
Immune function
Embryonic
development and reproduction
Bone metabolism
Haematopoieis
Skin health
Antioxidant activity
Слайд 10Sources of vitamin A
cod liver oil
meat
egg
milk
dairy products
carrot
broccoli
spinach
papaya
apricots
http://health.allrefer.com/health/nutrition.html
Слайд 11Vitamin D and imunity
It increases the activity of natural killer
cells (cytotoxic lymphocytes).
Increases the phagocytic ability of macrophages .
Reduces the
risk of virus diseases (colds, flu).
Reduces the risk of many cancers (colon, breast and ovarian cancer).
Reduces the risk of cardiovascular disease → have a positive impact on the composition of plasma lipids.
Слайд 12Sources of vitamin D
In addition to sunbathing:
various fish species (salmon,
sardines and mackerel, tuna, catfish, eel), fish oil, cod liver
eggs, beef liver, mushrooms
Слайд 13Vitamin C (Ascorbic acid )
Vitamin C is the most famous
vitamin.
sources: almost exclusively in foods from plant sources (citrus fruits,
broccoli, peppers, kiwi, strawberries, potatoes, tomatoes), although fresh milk and liver contain small amounts.
Слайд 14Major function in the body
helps form collagen
helps in growth and
repair of body tissue and blood vessels
prevents scurvy
a
strong antioxidant
aids in absorption of iron
helps regulate the metabolism of cholesterol and amino acids