Question 1

You eat frequently at fast-food restaurants. In order to improve the nutritional quality and vitamin A content of a typical fast-food meal you would:

Accepted Answer

Ordering a salad with cheese and carrots adds more nutrients to the meal, including vitamin A from the carrots. It also adds some fiber and protein from the cheese. Fries and cheeseburgers do not provide significant vitamins or nutrients, and juice can be high in sugar.

Question 2

Which of the following would provide the highest amount of vitamin E?

Accepted Answer

Wheat germ oil is an excellent source of vitamin E, containing about 20.3 mg per tablespoon. In comparison, whole milk contains about 0.1 mg per cup, a pork chop contains about 0.7 mg per 3 ounces, and a fried chicken leg contains about 0.2 mg per 3.5 ounces.

Question 3

Which of the following preparation or storage techniques for fruits and vegetables will preserve the most vitamins?

Accepted Answer

Stir-frying vegetables in a wok is the best choice for preserving the most vitamins as it involves cooking the vegetables quickly at high heat, which helps to retain their nutrient content. The other options involve exposure to air, light, or heat, which can lead to vitamin loss over time.

Question 4

Which of the following people would be able to make sufficient amounts of vitamin D without having to eat foods containing the vitamin?

Accepted Answer

Vitamin D is synthesized in the skin when it is exposed to sunlight. Therefore, someone who walks outdoors daily with light-weight clothing would be able to make sufficient amounts of vitamin D without having to eat foods containing the vitamin. Someone who always wears sunscreen when outdoors in the daytime (A) would not be able to synthesize enough vitamin D because sunscreen blocks UV light, which is necessary for vitamin D synthesis. Someone who works in an office in a northern urban area (B) would not receive enough sunlight exposure to synthesize vitamin D. Finally, someone with dark skin (D) requires more sunlight exposure than someone with light skin to synthesize the same amount of vitamin D because melanin impedes vitamin D synthesis.

Question 5

You have mixed a container of juice from its concentrate form and placed the open pitcher in the refrigerator to drink from over several days. Which vitamin in the juice is most at risk from the exposure to the air in the refrigerator?

Accepted Answer

Vitamin C is the most at risk as it is easily oxidized when exposed to air, light, and heat.

Question 6

All of the following might contribute to cases of rickets in the U.S. except:

Accepted Answer

Increased physical activity in organized sports would actually be beneficial towards preventing cases of rickets, as weight-bearing exercise helps the body to produce vitamin D, which is necessary for bone health. The other choices listed, increased time spent indoors, dark skin pigmentation, and a preference for soft drinks and punches over milk among adolescents, can contribute to cases of rickets.

Question 7

A young woman on a vegetarian diet has decided to increase her intake of raw bright-colored vegetables and has recently noticed that her skin is turning a bright yellow color. This is most likely a result of over-consumption of:

Accepted Answer

The bright yellow color of the skin is most likely due to the over-consumption of beta-carotene, a pigment found in many brightly colored fruits and vegetables. Beta-carotene is converted to vitamin A in the body and excess amounts can cause a temporary discoloration of the skin known as carotenemia. Folate, vitamin C, and biotin do not typically cause skin discoloration when consumed in excess.

Question 8

All of the following statements about vitamin A supplements and fortified foods are true except:

Accepted Answer

This statement is not entirely true. While it is generally true that the amounts of vitamin A added to fortified foods are not high enough to be a toxicity concern for most people, excessive consumption of fortified foods or supplements could still lead to vitamin A toxicity.

Question 9

You have a friend who eats a lot of highly processed foods, fast foods, and convenience foods, but does drink fortified milk. You tell your friend that she is at risk for developing _____ deficiency.

Accepted Answer

Highly processed foods, fast foods, and convenience foods are often low in vitamin E, which is found in nuts, seeds, and green leafy vegetables. Fortified milk typically contains vitamin D, not vitamin E.

Question 10

The statement, "Eat carrots because they are good for your eyes," is correct because:

Accepted Answer

Carrots contain beta-carotene which is converted to vitamin A in the body, and this vitamin A is essential for the production of rhodopsin, a pigment that is found in the retina of the eye and helps with vision in low light conditions. Therefore, eating carrots can be beneficial for maintaining good eye health. None of the other options mentioned in the question are accurate.

Question 11

Who would be at the greatest risk of developing osteomalacia?

Accepted Answer

The answer of Who would be at the greatest risk...

Question 12

A girl has stopped growing in height prematurely because her bones are not going through the remodeling process necessary for growth. This most likely results from a deficiency of which vitamin?

Accepted Answer

The answer of A girl has stopped growing in height...

Question 13

Tobacco use introduces into the body oxidants that can potentially harm body tissues. What antioxidant plays an important role in protecting sensitive blood constituents from being damaged, and so is needed in much higher amounts in people exposed to tobacco products and smoke?

Accepted Answer

Vitamin C is a water-soluble antioxidant that plays a vital role in protecting sensitive blood constituents, such as red blood cells, from being damaged by tobacco smoke. Smoking significantly increases the body's demand for vitamin C, making it essential for individuals exposed to tobacco products and smoke to consume larger amounts of this nutrient. Beta-carotene and vitamin E are fat-soluble antioxidants that also play important roles in protecting against oxidative damage but do not have as direct a role in protecting blood constituents as vitamin C. Vitamin K is not an antioxidant and does not play a significant role in protecting against oxidative damage caused by smoking.

Question 14

An individual has developed heart disease and high blood lipid values and refuses to take lipid-lowering prescription medications. Which vitamin might be suggested by his physicians as an alternative for lowering blood lipids?

Accepted Answer

Niacin (vitamin B3) has been shown to effectively lower blood lipid values, including LDL cholesterol and triglycerides, when taken in high doses. It can also increase HDL cholesterol levels. Therefore, it may be suggested as an alternative for someone who refuses to take prescription lipid-lowering medications. However, high doses of niacin can have side effects and should only be taken under medical supervision.

Question 15

A person who has taken antibiotics for several months because of a severe bacterial infection may develop a deficiency of:

Accepted Answer

Antibiotics can disrupt the normal gut bacterial flora, which is responsible for producing vitamin K. Therefore, a prolonged use of antibiotics can cause a deficiency in vitamin K.

Question 16

A person who lives in a city with high air pollution levels may be exposed to increased oxidative damage in the lungs from breathing the contaminated air. Which antioxidant vitamin is needed to protect the cells from damage?

Accepted Answer

Vitamin E is the antioxidant vitamin needed to protect the cells from oxidative damage in the lungs caused by air pollution. Vitamin E helps to neutralize harmful free radicals in the body and protect the cell membranes from oxidative damage. Vitamin A and vitamin K do not have direct antioxidant activity, while vitamin C is also an antioxidant but is more typically associated with protecting water-soluble areas of the body, such as the blood and its components.

Question 17

A woman who is on a low-carbohydrate diet for weight loss may have difficulty maintaining an adequate level of the B vitamins thiamin, riboflavin, niacin, and folate. What characteristic of her diet would cause this?

Accepted Answer

Thiamin, riboflavin, niacin, and folate are found in grain foods and cereals. Exclusion of these foods in a low-carbohydrate diet can lead to a deficiency in these B vitamins.

Question 18

Which of the following groups would not be at risk for developing a thiamin deficiency?

Accepted Answer

People who consume enough calories from whole foods, including whole grains and legumes, are not at risk for developing a thiamin deficiency. Thiamin is found in a variety of whole foods including fortified breads and cereals, whole grains, legumes, meat, and fish. People who are addicted to alcohol and those who consume polished rice as a food staple are at risk for developing a thiamin deficiency.

Question 19

Foods fortified with vitamin D are important because:

Accepted Answer

Very few foods have a naturally high vitamin D content, and not everyone will be able to obtain adequate exposure to the sun. Therefore, foods fortified with vitamin D are important to ensure adequate intake of this crucial nutrient. Option C is incorrect because it is not unsafe for older people to take vitamin D supplements, but they may need to consult with their healthcare provider to determine the appropriate dosage.

Question 20

You have a friend who has very little exposure to the sun and she consumes very few dairy foods. In addition, she has a 2-year-old child and 3-month-old twins. Your friend is at very high risk for developing:

Accepted Answer

Osteomalacia is a condition characterized by weakened bones due to vitamin D deficiency, which can occur in adults with limited sun exposure and low dietary intake of vitamin D, often found in dairy products.

Quiz 7: The Vitamins