Nutrition - Chapter 2

Steps of the scientific method (7)

1. Make observations to generate questions 2. Formulate a hypothesis 3. Review current scientific literature 4. Design studies, perform tests, collect data 5. Analyze data and draw conclusions 6. Share results 7. Conduct more research to confirm or refute findings

A researcher wants to identify lifestyle factors that increase the risk of stomach cancer in men. His study design involves enrolling 250 adult men who have stomach cancer and 250 men who are cancer-free but have similar characteristics and backgrounds as the men who have stomach cancer. The researcher collects and analyzes information about each participant's lifestyle. Based on this information, what kind of study is the researcher conducting? a. Case-control b. Cohort c. Experimental d. In-vivo

a

Scientists in a Central American country are studying factors that may be associated with delayed physical growth among a group of low-income children. The children live in a region of the nation that has high levels of lead in drinking water. This study is an example of a(an) ____ study. a. epidemiological b. uncontrollable c. introspective d. conventional

a

Which of the following kinds of studies would be the best to use when investigating whether cigarette smoking influences weight gain? a. Cohort b. Single-blind c. Double-blind d. Conventional

a

Which of the following nutrients is the most essential for life? a. Water b. Protein c. Omega-3 fatty acids d. Vitamin C

a

Which of the following statements is false? a. The Internet is generally a reliable source of nutrition information, because information posted at websites has been peer-reviewed. b. Websites with .edu in their addresses are likely to provide reliable nutrition information. c. When evaluating claims for dietary supplements that appear at a website, be wary of products that include promises for quick remedies. d. In general, personal websites, such as blogs, are not reliable sources of nutrition information.

a

Which of the following statements is true? a. Nutrient deficiency diseases develop when diets lack essential nutrients. b. A skin rash could be a symptom of a vitamin deficiency disease. c. A headache is a common sign of a mineral deficiency disease. d. Most phytochemicals are classified as essential nutrients.

a

Which of the following substances is a nutrient that does not provide any energy for the human body? a. Water b. Protein c. Carbohydrate d. Alcohol

a

A scientist thinks she has discovered an essential nutrient for humans, because this substance is a. required by cats and dogs. b. needed for the normal development of human cells. c. in most natural foods. d. easily manufactured by chemists.

b

The ____ is responsible for ensuring the safety and effectiveness of medications. a. EPA b. FDA c. NRC d. FTC

b

Which of the following substances is a nutrient that provides energy for humans? a. Alcohol b. Sugar c. Caffeine d. Thiamin

b

A serving of food supplies 144 kcal from protein. Based on this information, how many grams of protein are in the serving? a. 16 b. 26 c. 36 d. 46

c

According to the observations of a nutrition scientist, laboratory mice are healthier when their diet contains physiological levels of vitamin D than when their diet lacks the micronutrient. The scientist hypothesizes that mice will be less likely to develop cancer when they consume a diet that supplies megadoses of vitamin D. Based on this information, the scientist is ready to a. plan a retrospective study involving at least 5,000 laboratory mice to test the vitamin D and cancer hypothesis in mice. b. design a double-blind study to test the vitamin D and cancer hypothesis in mice. c. conduct a controlled laboratory experiment to test the vitamin D and cancer hypothesis in mice. d. set up an experimental epidemiological study to test the vitamin D and cancer hypothesis in mice.

c

Which of the following foods is both energy and nutrient dense? a. Strawberries b. Whole-grain bread c. Peanut butter d. Raw apples

c

Which of the following statements is true? a. According to the legal definition developed by the FDA, a "dietary supplement" is a food that influences metabolism. b. Physicians and dietitians do not recommend dietary supplements for their patients. c. Before taking a dietary supplement, people should determine whether the product is necessary and safe. d. People who develop side effects after taking dietary supplements can report their experiences to the GAO.

c

Which of the following statements is true? a. According to the legal definition developed by the FDA, a "dietary supplement" is a food that influences metabolism. b. Physicians and dietitians do not recommend dietary supplements for their patients. c. Dietary supplements may interact negatively with other substances a person takes. d. People who develop side effects after taking dietary supplements can report their experiences to the GAO.

c

Which of the following substances is a phytochemical? a. glucose b. zinc c. caffeine d. pantothenic acid

c

variable

personal characteristic or other factor that changes and can influence an outcome

anecdotes

reports of personal experiences

placebo effect

response to a placebo

epidemiology

study of the occurrence, distribution, and causes of health problems in populations

double-blind study

experimental design in which neither the participants nor the researchers are aware of each participant's group assignment

placebo

fake treatment, such as a sham pill, injection, or medical procedure

control group

group being studied that does not receive a treatment

treatment group

group being studied that receives a treatment

evidence based

information that is based on results of scientific studies

Popular health-related magazines typically publish articles that have been peer-reviewed.

False

Scientists use anecdotes as scientific evidence to support their findings.

False

By conducting a prospective epidemiological study, medical researchers can determine risk factors that may influence health.

True

Dietary supplements include vitamin pills as well as products that contain echinacea, ginseng, and garlic.

True

In general, registered dieticians are reliable sources of information about food and nutrition.

True

A group of scientists would like to determine lifestyle factors that are associated with the development of asthma among American children. Based on this information, the researchers should design a (an) _____ study. a. conventional b. in-vivo c. double-blind d. epidemiological

d

According to a main goal of Healthy People 2020, Americans should a. receive annual influenza vaccinations. b. reduce children's exposure to junk foods at home and school. c. learn how to obtain nutrition information from reliable sources. d. create environments that foster good health for everyone.

d

Researchers are conducting a study to determine the effects of zinc supplements on the human immune system. The study involves providing pills that contain zinc to one group of human subjects and pills that do not contain zinc or other active ingredients to another group of people. The pills that do not contain zinc are a. probiotics. b. supplements. c. antidotes. d. placebos.

d

The recommended dose of a vitamin is 2.0 mg. Based on this information, a megadose of the vitamin would be _____ mg or more. a. 4.0 b. 10.0 c. 15.0 d. 20.0

d