hsc 4572 Chapter 10
Give an example of a mineral that serves as a cofactor in chemical reactions that neutralize free radicals in the body
(multiple correct answers) -zinc -Mn -Fe -Cu
Select the carotenoids that can be converted into vitamin A in the body
-Alpha-carotene -beta-cryptozanthin -beta-carotene
Sources of provitamin A carotenoids include
-broccoli -carrots -sweet potatoes
Oxidative stress has been linked to the development of
-cancer -diabetes -Alzheimer's disease
Phytochemicals in foods such as _____ have been studied for their role in heart disease prevention
-chocolate -blueberries -citrus fruit
The vitamin E content of a food may be affected by
-exposure to oxygen -exposure to light -deep-fat frying
Recall that selenium has numerous functions, including
-glutathione peroxidase activity -thyroid hormone metabolism
A deficiency of selenium could disrupt normal function of which of the following?
-heart damage -muscle pain and wasting
What are the early symptoms of scurvy?
-joint pain -pinpoint hemorrhages -bleeding gums
Low levels of selenium have been linked to what type of cancer?
-prostate
Which of the following are beneficial functions of phytochemicals in the body?
-reduce cholesterol absorption -protection against free radical damage -mimic hormone activity
Nutrients reduce oxidative damage to cells and DNA by
-serving as cofactors in chemical reactions that neutralize free radicals -donating electrons to react molecules -accepting electrons from reactive molecules
Those at increased risk for a vitamin C deficiency include
-smokers -alcoholics
Groups who are at high risk of a vitamin E deficiency include
-smokers -preterm infants
Provitamin A carotenoids function as antioxidants and help to prevent
-some cancers -cardiovascular disease in high-risk people
Which of the following are good food sources of vitamin C?
-strawberries, 1 cup -red peppers, 1/4 cup -orange, 1 .
High intakes of dietary carotenoids so not result in toxicities because
-the efficiency of carotenoid absorption from the small intestine declines as intake decreases -the conversion of provitamin A carotenoids into vitamin A is slow and regulated
Which of the following statements describe free radicals?
-they are unstable -they can damage cell membranes -they have an imbalance between protons and electrons
The overall goals of medical nutrition therapy during cancer treatment are
-to prevent nutrient deficiencies -to minimize the loss of muscle mass
Select the nutrients that participate in the body's antioxidant defense systems
-vitamin E -vitamin C -selenium
Which of the following are functions of vitamin C?
-wound healing -formation of collagen
Typically, North American adults consume about ____ of the RDA for vitamin E from food sources
2/3
Which carotenoid is the only one that can be sufficiently absorbed and converted to retinol?
Beta-carotene
_____ as found in fruits and vegetables lessen the risk of macular degeneration and cataracts.
Carotenoids
cancer represents abnormal and uncontrollable division of cells that results from mutations in _______.
DNA
Vitamin E is implicated in the prevention of chronic diseases, such as cancer, cataracts, and cardiovascular disease, because
It can prevent oxidative damage
Those consuming megadoses of vitamin C should alert their physicians of this since megadoses can
alter the results of diabetes and blood in feces tests
Carotenoids may aid in the prevention of cardiovascular disease v=because of their ____ properties
antioxidant
Beta-carotene supplements ____ recommended for lung cancer prevention among smokers.
are not
Free radicals may damage DNA, leading to the development of
cancer
To improve intake of antioxidant nutrients,
choose a variety of brightly colored fruits and veggies
Mary tells you that she is taking 1 gram of vitamin C daily to prevent a cold. Which of the following is true regarding megadoses of vitamin C?
excess vitamin C is excreted from the body
What is the interaction between vitamin E and vitamin K?
excessive levels of vitamin E will reduce the clotting ability of vitamin K
When a person experiences oxidative stress, production of ____ in the body is high.
free radicals
When a person experiences oxidative stress, production of ______ in the body is high.
free radicals
The nutrients that have antioxidant properties and help block cancer development can be found in the food groups ____ and ____.
fruits and vegetables
Tomatoes, which contain the phytochemical lycopene in addition to many essential nutrients, can be considered
functional foods
What is the best understood role of selenium?
glutathione peroxidase activity
Vitamin C enhances the absorption of the mineral _____
iron
If cancer is left untreated it can ______, which means it can spread to distant sites of the body
metastasize
excess calorie intake, eventually leading to ____, is the main diet-cancer risk factor
obesity
About half of all chemical reactions in the body involve the exchange of electrons. When a compound in a reaction loses an electron, that compound has been
oxidized
Which food sources are naturally higher in vitamin E?
plant
The deficiency disease for vitamin C is called_____
scurvy
Which of the following minerals participates in antioxidant reactions?
selenium
Possible side effects of high intake levels of vitamin-A yielding carotenoids include
skin that becomes yellow-orange in color
When an antioxidant chemical donates an electron to a free radical,
the antioxidant becomes unstable, but does not cause cellular damage
The chemical name for the four forms of vitamin E is
tocopherols
Which vitamin has been shown to promote resistance to infection?
vitamin C
The fat-soluble antioxidant vitamin responsible for protecting cell membranes by helping to stop damage by free radicals is
vitamin E
Select the food source that has the least amount of selenium per serving
white bread