Chapter 11 "The Fat-Soluble Vitamins: A, D, E, and K
Osteomalacia
softening of the bone
what physical conditions can result from too much Vitamin For Vitamin A toxicity?
such effects are unlikely when a person depends on a balanced diet for nutrients
Osteoporosis
A condition in which the body's bones become weak and break easily.
what role does Vitamin A play on Beta-carotene as an Antioxidant?
It serves as a vitamin A precursor. Some beta-carotene acts as an antioxidant capable of protecting the body against disease.
The three different forms of vitamin A known as the retinoid are....
Retinol Retinal and Retinoid acid
what are the major food sources of Vitamin E?
Vegetable oils Seeds Nuts Green leaf veggies
what is hemorrhagic disease and why may Vitamin K be helpful in preventing this ?
a disease characterized by excessive bleeding. An adequate intake of vitamin K helps to decrease bone turnover and protect against fractures.
like Vitamin D, Vitamin K can be obtained from a non-food source. How is it obtained or made ?
bacteria in the GI tract synthesize vitamin K. The diet must also supply vitamin K, which is primarily found in leafy green vegetables.
what role does Vitamin A play on Protein Synthesis and Cell Differentiation?
both vitamin A and beta-carotene help to protect against skin damage from sunlight.
how may Vitamin E reduce the risk of heart disease?
by protecting low-density lipoproteins (LDL) against oxidation and reducing inflammation.
why is Vitamin A needed to prevent Blindness ?
caused by a lack of Vitamin A at the front of the eye; cornea. Severe vitamin A deficiency is the leading cause for this..
What foods are easily converted to retinol?
foods derived from animals
Vitamin D is not actually a vitamin, what is it ?
hormone
Vitamin D- What makes it different than all the other nutrients in the body and why?
in that the body can synthesize it, with the help of sunlight, from a precursor that the body makes from cholesterol. Vitamin D is not an essential nutrient; given enough time in the sun, people need no vitamin D from foods.
when there is a Vitamin D deficiency, what happens to calcium?
it creates a calcium deficiency and increases the risks of several chronic diseases and osteoporosis.
what are the roles of Vitamin E as an antioxidant, specifically related to free radicals and fatty acid oxidation?
it is a fat-soluble antioxidant and one of the body's primary defenders against the adverse effects of free radicals.
which group of people are most likely to suffer from Vitamin D deficiencies and why ?
most likely in older adults. the skin, liver, and kidneys lose their capacity to make and activate vitamin D with advancing age. Also because adults drink little to no milk. Finally, adults typically spend much of the day indoors.
what is Vitamin K's primary role ?
primary action is blood clotting
Briefly explain the carotenoids and what foods provide them.
they can be converted to vitamin A. Plants
What is vitamin D's role in bone growth and how does it do it ?
to assist in the absorption of calcium and phosphorus, thus helping to maintain blood concentrations of minerals.
why is Vitamin A needed to prevent Infectious Diseases?
vitamin A supports immune function and inhibits replication of the measles virus.
Rickets
vitamin D deficiency disease in children characterized by inadequate mineralization of bone (bowed legs or knock-knees, outward-bowed chest, and "beads" on ribs)
what role does Vitamin A play on Reproduction and Growth ?
In women, vitamin A supports normal fetal development during pregnancy. Children lacking vitamin A fail to grow. given vitamin A supplements, these children gain weight and grow taller.
what are the three diseases that can occur as a result of Vitamin D deficiency and briefly explain them?
Rickets Osteomalacia Osteoporosis
what is the most studied carotenoid and what can it be used to form?
beta-carotene. Can be split to form retinol in the intestine and liver.
why can't Beta-carotene cause Vitamin A toxicity?
it is not converted efficiently enough in the body to cause vitamin A toxicity; instead it is stored in the fat just under the skin.
why is Vitamin A needed to prevent Night Blindness ?
it is one of the first signs to detect it. This issue is caused by a lack of Vitamin A at the back of the eye; retina.
what role does Vitamin A play on Vision?
plays two indispensable roles in the eye: it helps maintain a crystal-clear outer window, the cornea, and it participates in the conversion of light energy into nerve impulses at the retina.
why is Vitamin A needed to prevent Keratinization?
without vitamin A, the goblet cells in the GI tract diminish in number and activity, limiting the secretion of mucus.
what role does vitamin K play in the bone proteins?
without vitamin K, osteocalcin cannot bind to the minerals that normally form bones, resulting in low bone density.