Nutrition Chapter 8
Which group is LEAST at risk for developing vitamin C deficiency?
Adults who consume plenty of fruits and vegetables
Elevated homocysteine is associated with increased risk of cardiovascular disease. In clinical studies, which vitamins have been shown to decrease homocysteine levels in the blood?
B6, folate & B12
how well a vitamin is absorbed and used by the body
Bioavailability
Which disease is caused by niacin deficiency?
Pellagra
Vitamin C deficiency causes:
bleeding gums.
Pellagra occurs when _________ is the staple grain in the diet and the diet does not provide a mixture of different foods.
corn
Vitamins may be lost when food is processed. When these vitamins are added back to the processed food at the same or higher level, the food is said to be:
enriched
Milk products are usually packaged in opaque bottles due to the fact that:
exposure to light causes degradation.
Folate deficiency symptoms are less of a problem recently because:
grain products are now fortified with folate
High folate intake may:
mask a vitamin B12 deficiency, giving rise to permanent nerve damage.
Vitamin B12 deficiency caused by a lack of intrinsic factor results in:
pernicious anemia.
The ____________ is the site of most vitamin absorption into the body.
small intestine
Which lifestyle factor increases the requirement for vitamin C?
smoking cigarettes
Beriberi is a disease caused by lack of ________ in the diet.
thiamin
Meeting vitamin B12 needs from the diet is especially difficult for:
vegans
Folic acid supplements are most frequently recommended for:
women who may become pregnant.
major functions of vitamin C in the body
-Formation of collagen -Protection against damage from free radicals -Enhancing iron absorption
Vitamin B6 is involved in which physiologic processes?
-Formation of non-essential amino acids -Hemoglobin synthesis -Formation of white blood cells important for immunity
Which is a good dietary source of thiamin?
-Sunflower seeds -Pork -Whole grains
Absorption of vitamin B12 is dependent upon:
-adequate stomach acid. -pepsin. -intrinsic factor.
Riboflavin forms active coenzymes that do:
-assist with energy production from carbohydrates, proteins and fats. -function as electron carriers. -participate in the citric acid cycle.
Symptoms of ariboflavinosis include:
-inflammation of the eyes and mouth. -scaly, greasy skin eruptions. -confusion.
Choline deficiency may contribute to:
-neurological disorders. -atherosclerosis. -liver disease.
The process of bioavailability related to vitamin requirements is affected by:
-solubility. -transport systems. -precursors. -carrier proteins.
Which group of people is most at risk for developing thiamin deficiency?
Chronic alcoholics
Pantothenic acid forms part of which molecule?
Coenzyme A
A person consuming a diet deficient in dairy products but otherwise adequate, would have the most difficulty obtaining sufficient amounts of which vitamin?
Riboflavin
Biotin is tightly bound by avidin, which prevents absorption of the vitamin. Avidin is commonly found in:
egg whites
A primary function of thiamin is to:
facilitate the production of energy from glucose.
A common adverse effect of niacin toxicity is:
flushing of the skin
Which B vitamin decreases the risk of neural tube defects in developing babies?
folic acid
The process of adding nutrients to foods is called:
fortification
The RDA for B6 in adults ____________ with aging.
increases
can be synthesized in the body from the amino acid tryptophan
niacin