Ch. 11: The Fat-Soluble Vitamins: A, D, K and E
Substance that causes abnormal fetal development and birth defects
teratogen
Over consumption of beta-carotene in food products is associated with :
the skin turning yellow
Retinoic Acid
Acid form of Vitamin A that supports growth
How is vitamin E thought to play a role in reducing the risk of heart disease?
It slows oxidation of low density lipoproteins
When the cornea softens it is called
Keratomalacia
Vitamin E Deficiency
May lead to erythrocyte hemolysis (seen in premies) which can then lead to hemolytic anemia -Prolonged deficiency may cause neuromuscular dysfunction leading to loss of muscle coordination and reflexes and nerve damage
Vitamin A Reproduction and Growth in Men, Women and Children
Men: sperm production Women: fetal development Children: bone remodeling
The first detectable sign for deficiency of vitamin A
Night Blindness
Vitamin D deficiency in adults, poor mineralization of bone, bone becomes increasingly soft, flexible, brittle and deformed
Osteomalacia
Vitamin D deficiency most common in elderly causing loss of calcium from bones and resulting in fracture
Osteoporosis
Xeropthalmia
Progressive blindness caused by vitamin a deficiency due to inadequate mucus production that damages the cornea.
Food source for vitamin K
green leafy vegetables
Vitamin K deficiency
- Can lead to hemorrhagic disease which causes excessive bleeding -Reduces bone density
Vitamin A Roles
- Promote vison (retinal) -Participates in protein synthesis and cell differntiation (retinoic acid) -Supports reproduction and regulates growth (retinol) -Stored in liver
Vitamin A deficiencies
- leads to increase risk of infectious diseases (mucous membrane) - Night blindness - Blindness (Xerotpthalamia) - Keratinization
Main function of vitamin E is :
to act as an antioxidant
Typical food source of Vitamin E
vegetable oils
What do fat soluble vitamins require for digestion?
Bile
Vitamin E Sources
Found in plant oils, nuts and seeds
Vitamin K Functions
Functions in the synthesis of blood clotting proteins (prothrombin) and bone proteins (osteocalcin) that regulate blood calcium
Type of anemia prevented by vitamin E
Hemolytic anemia
Vitamin E Functions
To prevent the oxidation of polyunsaturated fatty acids and LDL - Functions as an antioxidant to donate electrons to free radicals
Retinal
Aldehyde from of vitamin A that supports vision
Use of this increases risk for vitamin K deficiency
Antibiotics
Antioxidant found in deep orange fruits and deep orange vegetables and vitamin A precursor
Beta-carotene
Vitamin K Sources
Can be made by bacteria in the GI tract but leafy green vegetables are a good source
Vitamin D Toxicity
Can lead to hypercalcemia or really high blood calcium and may contribute to formation of kidneys stones
Precursor for vitamin D synthesis
Cholesterol
Vitamin A Sources
Cornflakes, broccoli, carrots, tomato juice, liver, mango, sweet potato
Vitamin A toxicity symptoms
Damage to the liver and bone defects (osteoporosis) High doses of this vitamin during pregnancy may lead to birth defects
Factors that contribute to Vitamin D deficiency:
Dark skin breastfeeding without supplementation Lack of sunlight Not using fortified milk
Vitamin D Sources
Fortified milk sunlight egg yolks salmon
Where are fat soluble vitamins stored?
Liver and adipose tissue
3 forms of Vitamin A
Retinol, Retinal and Retinoic Acid (Retinoids)
The specific protein responsible for transporting vitamin A from the liver into the blood
Retinol-binding protein (RBP)
Vitamin D deficiency in children causing childs legs to bend
Rickets
How does Vitamin D differ from other nutrients?
The body can synthesize them with the help of sunlight and from a precursor that the body makes from cholesterol.
What happens during Keratinization?
The epithelial cells change shape and begin to secrete the protein keratin causing the skin to become dry, rough and scaly .
Vitamin D Functions
To maintain blood calcium and phosphorus levels and assists in their absorption stimulates retention by kidneys
Can be made naturally from sunlight and a precursor derived from cholesterol
Vitamin D
Most common deficiencies in the US
Vitamin D
Rickets Osteomalacia and calcium deficiency
Vitamin D Deficiencies
Substance that promotes synthesis of prothrombin
Vitamin K
This vitamin is injected into infants at birth
Vitamin K
Which fat soluble vitamin is synthesized by intestinal bacteria?
Vitamin K
When the cornea becomes dry it is called..
Xerosis
Retinol
alcohol form of vitamin a that supports reproduction
Vitamin K toxicity
can decrease the effectiveness of anticoagulants
Keratinization may result from
deficiency of vitamin A
Vitamin E deficiency disorder
erthrocyte hemolysis
Rhodopsin
is a protein combined with retinal; under goes bleaching process: converting cis to trans-Retinal. Allowing the nerve impulse to be sent to the brain about what you're seeing.
Vitamin E Toxicity
rare; but it could act as a blood thiner, hemorrhagic effects