8. dynamic module: Vitamins

Which of the following would increase vitamin E in a salad? -All options are correct. -olive oil -chopped nuts -avocado slices

All options are correct. All options are correct. Olive oil, chopped nuts, and avocado slices are good sources of fat-soluble vitamin E. Vegetable oils, seeds, green leafy vegetables, and fortified cereals also contribute to an individual's daily intake of vitamin E.

Vitamin D is _____. -All options are correct. -a hormone -made in the body with the help of sunlight -found in fortified milk

All options are correct. All options are correct. Vitamin D is a hormone that plays multiple roles in the body, including in calcium regulation. A deficiency of vitamin D can cause rickets in children and osteomalacia and osteoporosis in adults. Although vitamin D can be made in the body with the help of sunlight, many individuals are not exposed to enough sunlight to meet their needs. Fortified milk and soymilk are excellent sources of vitamin D.

Vitamin ___ is called the "sunshine vitamin." -D -E -C -K

D Vitamin D is called the "sunshine vitamin" because it is made in the body with the help of ultraviolet rays from sunlight. Many individuals do not obtain enough sun exposure, so they must meet their needs through their diet. However, naturally occurring vitamin D sources in food are scarce, and many Americans fall short of their daily requirement of vitamin D. The best ways to obtain vitamin D from food is to consume fatty fish (such as sardines and salmon) and fortified foods and beverages such as milk or soymilk, breakfast cereals, and yogurt. Vitamin E's nutritional claim to fame is its role as a powerful antioxidant. This role is extremely important in protecting cell membranes and preventing oxidation of the "bad" LDL cholesterol carrier. Vitamin C, also known as ascorbic acid, assists in the formation of collagen. It is also an antioxidant and has many other functions. Vitamin K helps blood to clot and helps synthesize proteins that keep bones healthy.

Naturally occurring vitamin B12 is found in which of the following foods? -Eggs and beef -Watermelon and strawberries -Whole-grain bread and pasta -Nuts and seeds

Eggs and beef Naturally occurring vitamin B12 is found only in foods from animal sources, including eggs and beef and other meats, fish, poultry, and dairy products. Individuals who consume a varied diet that includes the minimum recommended servings of these food groups will easily meet daily B12 requirements. Though lacking naturally occurring B12, colorful fruits (including watermelon and strawberries) and vegetables, whole grains, and nuts and seeds provide plant oils and proteins, vitamins, minerals, dietary fiber, and disease-fighting phytochemicals.

Which B vitamin is critical for DNA synthesis and cell division? -Folate (folic acid) -Pyridoxine -Biotin -Pantothenic acid

Folate (folic acid) Folate (folic acid) is critical for DNA synthesis and cell division. Folate is naturally found in foods, especially leafy green vegetables, but is more easily absorbed in its synthetic form, folic acid. Folic acid is found mostly in fortified foods such as breads and breakfast cereals and in supplements. Pyridoxine, the major form of vitamin B6, acts as a coenzyme for over 100 enzymes. Vitamin B6 is also a key player in red blood cell synthesis and in keeping the immune and nervous systems healthy. Pantothenic acid and biotin are both B vitamins that aid in metabolism.

Which of these statements is FALSE? -It is necessary for individuals to consume vitamin supplements in order to meet their daily vitamin needs. -Dietary supplements, a category that includes vitamins, minerals, and herbs, are regulated less stringently by the Food and Drug Administration (FDA) than are drugs. -The U.S. Pharmacopoeia (USP) sets standards for the identity, strength, quality, and purity of dietary supplements. -Supplement manufacturers can voluntarily submit their products to the U.S. Pharmacopoeia (USP) to verify their supplement meets current standards.

It is necessary for individuals to consume vitamin supplements in order to meet their daily vitamin needs. It is NOT necessary for individuals to consume vitamin supplements in order to meet their daily vitamin needs. Fortified foods and vitamin supplements can help individuals with inadequate diets or certain diseases to meet their nutrient needs; however, supplements should never replace a nutrient-dense diet. Dietary supplements, a category that includes vitamin and mineral supplements, are regulated less stringently by the Food and Drug Administration (FDA) than are drugs. The U.S. Pharmacopoeia (USP) sets standards for the identity, strength, quality, and purity of dietary supplements. Supplement manufacturers can voluntarily submit their products to the USP to verify their supplement meets current standards.

Adam is 65 years old. Which of the following nutrients might his body have difficulty absorbing? -Vitamin B12 in a sirloin steak -Iron in a sirloin steak -Folate in spinach -Riboflavin in milk

Vitamin B12 in a sirloin steak At 65 years of age, Adam might have difficulty absorbing the vitamin B12 in a sirloin steak. A certain level of both gastric acid (stomach acid) and intrinsic factor (secreted by gastric cells) are needed to release vitamin B12 from the proteins in food and make it available for absorption. Approximately 10 to 30 percent of adults over the age of 50 have gastric acid levels too low to free up the vitamin B12 that is found naturally in food, and intrinsic factor production can also decline with age. Synthetic vitamin B12, the vitamin form that is found in fortified foods and supplements, is not bound to protein. Therefore, its absorption is not affected by levels of these secretions. Adults over 50 years of age can best meet their vitamin B12 needs from fortified foods, supplements, or injections of vitamin B12. previous

Folic acid, if consumed prior to and during the first several weeks of pregnancy, can help reduce the risk of giving birth to a newborn with _____ . -a neural tube defect -cretinism -night blindness -fetal alcohol syndrome

a neural tube defect If consumed prior to and during the first several weeks of pregnancy, adequate amounts of folic acid can help reduce the risk of giving birth to a newborn with a neural tube defect, such as spina bifida or anencephaly. Adequate maternal intake of iodine, not folate, reduces the risk for cretinism (a form of brain damage associated with iodine deficiency). Adequate vitamin A or beta-carotene intake can help prevent night blindness in children and adults. Total avoidance of alcohol consumption throughout pregnancy can prevent fetal alcohol syndrome.

Fat-soluble vitamins are ____. -absorbed into the lymphatic system -synthesized by beneficial bacteria in the large intestine -critical to energy metabolism -derived only from animal-based foods

absorbed into the lymphatic system Fat-soluble vitamins are packaged into micelles, cross the lining cells of the small intestine, and are then repackaged into chylomicrons, which are absorbed into the lymphatic system. Although vitamin K is synthesized by bacteria in the large intestine, vitamins A, D, and E are not. The B vitamins, not the fat-soluble vitamins, are critical to energy metabolism. Vegetables, not animal-based foods, are rich in vitamins E and K. Vitamin A is most abundant in meats, especially liver, but provitamin A carotenoids are plant pigments. Fatty fish is a good source of vitamin D, but it is also added to some plant-based foods such as soy milk, and it can be synthesized in the skin with adequate exposure to sunlight.

The primary role of the B vitamins is to ____. -act as coenzymes in energy metabolism and many other metabolic reactions -provide a source of energy -build and repair body tissues -synthesize collagen

act as coenzymes in energy metabolism and many other metabolic reactions The primary role of the B vitamins is to act as coenzymes in energy metabolism and many other metabolic reactions. Thiamin, riboflavin, niacin, vitamin B6, folate, vitamin B12, pantothenic acid, and biotin are known collectively as the B vitamins. Although vitamins are not a source of energy, the body needs many of the B vitamins to convert the three energy-yielding nutrients (carbohydrates, proteins, and fat) to energy (ATP). Vitamin C, also known as ascorbic acid, helps synthesize collagen. Collagen is the key component of the connective tissue, so this protein is needed to build and maintain healthy bones, teeth, skin, and blood vessels.

Choline is __________ . -an essential nutrient -one of the B vitamins -available from very few foods -All options are correct.

an essential nutrient Choline is an essential nutrient. The body is able to synthesize it, but not in sufficient amounts to meet its needs. Therefore, it must be consumed in the diet. Fortunately, it is available from a wide range of foods. Although it behaves like a vitamin, it is not classified as a vitamin.

Vitamin E functions as a(n) ________ to protect cell membranes from being damaged. -antioxidant -free radical -neutrophil -anticoagulant

antioxidant Vitamin E functions as an antioxidant to protect cell membranes from being damaged. Vitamin E neutralizes free radicals before they can harm phospholipids in cell membranes. Many phospholipids contain unsaturated fatty acids, which are vulnerable to the damaging effects of free radicals.

A chronic deficiency of thiamin can cause _____. -beriberi -rickets -scurvy -osteomalacia

beriberi A chronic deficiency of thiamin can cause beriberi. This disease can affect the nervous system and result in weakness and even paralysis. The main dietary source of thiamin is enriched grains (which have many B vitamins and iron added to them), which Americans consume frequently. However, in poor nations with limited access to food, reliance on non-enriched grains increases the risk for beriberi. Additionally, alcohol intake interferes with thiamin absorption in the body. Therefore, those who chronically abuse alcohol are susceptible to a thiamin deficiency and the side effects of beriberi. A vitamin D deficiency can cause rickets in children and osteomalacia in adults. Scurvy is the result of a vitamin C deficiency.

All of the following conditions are associated with a deficiency of vitamin D EXCEPT ______. -beriberi -osteoporosis -osteomalacia -rickets

beriberi Beriberi is not associated with a deficiency in vitamin D. It is a disease that occurs in humans who are deficient in thiamin. Osteoporosis, osteomalacia, and rickets are all bone disorders associated with a deficiency of vitamin D. Lack of vitamin D leads to inadequate absorption of calcium and phosphorus. The bones of children with rickets aren't adequately mineralized and thus are weak, knock knees and bow- shaped. Osteomalacia is the adult equivalent of rickets. Osteoporosis is a disorder characterized by low bone density, which causes the bones to become brittle and prone to fracture.

A plant pigment that the body can convert to vitamin A is _____. -beta-carotene -retinol -Retin-A -rhodopsin

beta-carotene Beta-carotene is a plant pigment that the body can convert to vitamin A. Retinol is the most usable form of vitamin A in the body. Retin-A is an acne medication that contains retinoids. Rhodopsin is a vitamin-A containing protein required for healthy vision.

High consumption of raw egg whites can lead to a deficiency of which vitamin? -biotin -vitamin A -niacin -vitamin C

biotin High consumption of raw egg whites can lead to a deficiency in the B vitamin biotin. Raw egg whites contain the protein avidin, which binds with biotin and blocks it from absorption in the intestine. Cooked eggs are not a problem because heat breaks down and inactivates the protein, allowing biotin to be absorbed. Biotin deficiency can cause hair loss, depression, fatigue, nausea, and skin rashes.\ Vitamin A deficiency can lead to night blindness and damage to the cornea, known as xerophthalmia. Niacin deficiency causes pellagra, which can result in dermatitis, dementia, depression, and even death. Vitamin C deficiency leads to scurvy, which leads to tissue breakdown and bleeding and can also be fatal.

A deficiency of vitamin B12 can cause ________. -macrocytic anemia -microcytic anemia -scurvy -pellagra

macrocytic anemia A deficiency of vitamin B12 can cause macrocytic anemia. This form of anemia is characterized by large, immature red blood cells. When there isn't enough vitamin B12 available, folate can't be utilized properly to help red blood cells divide. A folate deficiency can also cause macrocytic anemia. Microcytic anemia is a form of anemia in which the red blood cells are smaller than normal, resulting from a deficiency of iron or vitamin B6. Scurvy is a disease caused by a deficiency of vitamin C. This deficiency impairs collagen synthesis. The signs and symptoms of scurvy include wounds that fail to heal, bleeding gums, fractures, and other signs of tissue breakdown, as well as diarrhea, weakness, and depression. A deficiency of niacin results in pellagra, which can result in dermatitis, dementia, depression, and even death.

All of the following are good sources of vitamin C EXCEPT ________. -milk -strawberries -potatoes -broccoli

milk Milk is not a good source of Vitamin C. However, it is a good source of riboflavin, vitamin B12, pantothenic acid, biotin, and choline. Fortified milk is a good source of vitamin D and preformed vitamin A; however, milk does not contain vitamin C. Most Americans associate vitamin C with citrus fruits, and indeed, one serving of either orange juice or grapefruit juice will just about meet an adult's daily needs. But a wide variety of fruits and vegetables provide vitamin C. Strawberries, broccoli, and even potatoes are good sources. One medium potato provides about 70 percent of an average adult's needs.

A deficiency of which vitamin causes signs and symptoms characterized by the four Ds: dermatitis, dementia, diarrhea, and death? -niacin -thiamin -vitamin C -cobalamin

niacin A deficiency of niacin causes pellagra, which is characterized by the four Ds: dermatitis (skin inflammation), dementia (confusion and memory loss), diarrhea, and death. Niacin, or vitamin B3, is needed to metabolize the energy-yielding macronutrients—carbohydrates, fats, and proteins. Niacin is found in enriched grains, which are consumed abundantly in America, so pellagra is rare in the United States. However, pellagra can occur with alcohol abuse or a very poor diet. Thiamin, or vitamin B1, deficiency is known as beriberi and causes weakness and paralysis. Deficiency of vitamin C causes scurvy, and deficiency of cobalamin, or vitamin B12, causes macrocytic anemia and impairs the nervous system.

In a vegan breakfast consisting of raisin bran cereal with soy milk and a glass of orange juice, the vitamin C in the orange juice will enhance the absorption of _____. -the iron and calcium in the cereal -the bran in the cereal -the vitamin D in the fortified soy milk -the calcium in the fortified soy milk

the iron and calcium in the cereal The vitamin C in the orange juice will enhance the absorption of the iron and calcium in the cereal. Vitamin C does not affect the absorption of vitamin D. However, the vitamin D in the soy milk will help you absorb the calcium that is also in the cereal. Bran is a form of dietary fiber and is not absorbed by the body.

Which of the following can be destroyed by exposure to water or heat? -the water-soluble vitamins (B vitamins and vitamin C) -the fat-soluble vitamins (vitamins A, D, E, and K) -major minerals -trace minerals

the water-soluble vitamins (B vitamins and vitamin C) The water-soluble vitamins (B vitamins and vitamin C) can be destroyed by exposure to water or heat. When foods such as vegetables are soaked in water or cooked in large amounts of water, water-soluble vitamins leach into the water. To reduce vitamin loss, cook vegetables in a minimal amount of liquid. Cooking vegetables until "just tender" is best, as it reduces the cooking time and heat exposure and preserves the vitamins. Although the fat-soluble vitamins (A, D, E, and K) tend to be more stable than water-soluble vitamins, some food preparation techniques can cause the loss of these vitamins as well. Minerals cannot be destroyed by exposure to water or heat.

A deficiency of vitamin A can result in _______. -vision problems -neural tube defects, such as spina bifida -pellagra -inability to clot blood

vision problems A deficiency of vitamin A can result in vision problems. A chronic vitamin A deficiency can lead to an inability to regenerate the light-sensitive protein rhodopsin, causing night blindness. A prolonged vitamin A deficiency can also lead to dryness and permanent damage to the cornea. Vitamin A deficiency is the number-one cause of preventable blindness in children. A deficiency of folate during pregnancy can result in birth defects called neural tube defects, such as spina bifida. A deficiency of niacin results in pellagra, which can result in dermatitis, dementia, depression, and even death. Vitamin K plays a major role in blood coagulation, or clotting. Without vitamin K, the body would lack the ability to clot blood. previous

Which nutrient is involved in collagen formation and immune and antioxidant defenses? -vitamin C -pantothenic acid -thiamin -riboflavin

vitamin C Vitamin C, also known as ascorbic acid, is involved in collagen formation and and immune and antioxidant defenses. Collagen, the most abundant protein in the body, is necessary for healthy bones, teeth, cartilage, ligaments, tendons, skin, and blood vessels. As an antioxidant, vitamin C reduces free radical damage. It also helps with the production of white blood cells, key players in a healthy immune system. Vitamin C also enhances absorption of dietary iron and calcium. Pantothenic acid aids in the metabolism of the nutrients that provide energy: carbohydrates, proteins, and fats. Thiamin is needed for nerve function and energy metabolism. Riboflavin is important for energy metabolism and healthy cells.

Which of the following is/are considered antioxidants? -vitamin E and beta-carotene -vitamin A and vitamin D -vitamin D and vitamin K -vitamin B12 and beta-carotene

vitamin E and beta-carotene Vitamin E and beta-carotene are considered antioxidants. Vitamin E donates an electron to free radicals, thereby stabilizing them. Beta-carotene is a weaker antioxidant. Free radicals can contribute to chronic diseases such as cancer and cardiovascular disease and accelerate the aging process. They also contribute to age-related macular degeneration and cataracts. Diets abundant in antioxidant-rich fruits, vegetables, and whole grains are associated with a lower incidence of many diseases. Vitamin C is also an antioxidant. Vitamin K helps synthesize proteins important to blood clotting and bone health. Vitamin A is involved in vision, reproduction, and cell differentiation, and may have a weak antioxidant role. Vitamin D is involved in in calcium balance and bone health. Vitamin B12 is involved in DNA synthesis and red blood cell formation.

Which vitamin is essential for blood to clot? -vitamin K -vitamin D -vitamin B6 vitamin A

vitamin K Vitamin K is essential for blood to clot. Vitamin K helps synthesize four clotting factors that are involved in the complex chain of events that causes blood clotting. Without vitamin K, a simple cut on the finger would cause uncontrollable bleeding. Vitamin B6 is a coenzyme and is part of over 100 chemical reactions in the body. Vitamin D is necessary for regulation of calcium and phosphorus. Vitamin A refers to a family of retinoids that are needed for strong vision, reproduction, and healthy fetal development.

Which of the following vitamins is fat soluble? -vitamin K -vitamin C -vitamin B6 -folic acid

vitamin K Vitamin K is fat soluble. A vitamin is either fat soluble or water soluble, depending on how it is absorbed and handled in the body. The fat-soluble vitamins A, D, E, and K are stored in the body and require dietary fat for absorption. They can accumulate to the point of toxicity if intake is excessive. The water-soluble B vitamins (including vitamin B6 and folic acid) and vitamin C are absorbed with water and typically aren't stored in the body for extended periods. Excess amounts of water-soluble vitamins do not accumulate to toxic levels, but they can be harmful if routinely over-consumed in large doses.

Which of the following nutrients can accumulate to the point of toxicity if intake is excessive? -vitamins A, D, E, and K -thiamin, riboflavin, niacin, and pyridoxine -folate, pantothenic acid, vitamin B6, and vitamin B12 -vitamins E, C, and D and biotin

vitamins A, D, E, and K Because they are fat-soluble, vitamins A, D, E, and K are stored in the body and can accumulate to the point of toxicity if intake is excessive. Water-soluble vitamins—including vitamin C and the B vitamins—are typically not stored in the body for long periods of time, and excess amounts are excreted in urine.