Evaluating sources of nutrition information
The Internet is full of nutrition information—
On an Internet search engine, look up a nutrition question that interests you. For example, “Do some foods make you smarter?” “What are the best food sources of calcium?” What article did you select?
On what kind of Web site does the information appear? Is it a .com, .edu, or .gov?
Is the author of the article listed? If not, can you determine who might have written it?
Is there any evidence that the author of the information has some authority in the field of nutrition or health? What are the author’s qualifications, credentials, and connections to the subject?
Who is the intended audience for this information? Is the audience a scholarly one? If so, does the article include a clear bibliography that you can consult for further sources?
Are there clues that the author is biased? For example, is the author selling or promoting a product? Is the author taking a personal stand on a social or political issue? Describe how the the article is biased, or provide evidence that it is unbiased.
How timely is the information? When was the information published?
To verify the credibility of the source, search for additional texts on the topic to find related sources, and sources that cite this source to better understand its intellectual value. Overall, does this appear to be a credible article? Explain.
Take It Further
The Academy of Nutrition and Dietetics publishes Position and Practice Papers on a variety of nutrition topics as related to health and disease. Visit www.eatright.org to learn more about the organization. Under the “Health Professionals” tab on the home page you will find a link to the Position and Practice Papers. After accessing this link, click on “What Is an Academy Position Paper?” and browse the list of position papers. Choose one and read the abstract and skim the paper.
What Position Paper was of interest to you and why?
Was any other professional organization involved in the development and publication of this Position Paper? If so, what organization(s) partnered with the Academy of Nutrition and Dietetics?
List two to three pertinent facts or findings from the Position Paper abstract or article.
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Nutrition science is an interdisciplinary field that studies dietary intake and behavior, as well as the nutrients and constituents in food, their use by the body, and their influence on human health.
Nutrients are chemical substances obtained from food that are required for normal growth, development, reproduction, and tissue maintenance and repair. They include the macronutrients—
Phytochemicals are a dietary constituent found in plant foods that are beneficial to human health.
Unbalanced nutrition, or malnutrition, can be the consequence of undernutrition, which may result in nutrient deficiencies, or overnutrition, which may result in accumulation of excess body fat or obesity.
Diet plays a significant role in the risk, progression, and treatment of most chronic diseases. Excess consumption of calories, animal fats, sugar, and sodium is linked with increased risk of the leading causes of mortality.
The Dietary Reference Intake values (DRIs) are issued by the Institute of Medicine and provide quantitative estimates of recommended nutrient intake for individuals on the basis of sex, age, and life stage.
The DRIs are intended to help prevent nutrient deficiency, promote overall health, prevent disease, and avoid excess intake. To support these goals and provide more comprehensive nutrient recommendations, the DRIs encompass Estimated Average Requirements (EARs), Recommended Dietary Allowances (RDAs), Adequate Intakes (AIs), and Tolerable Upper Intake Levels (ULs).
The DRIs establish Acceptable Macronutrient Distribution Ranges (AMDRs) for carbohydrates, proteins, and fats expressed as a percent of total calories.
Estimated Energy Requirements (EERs) are also established within the DRIs as average energy intakes needed to maintain weight in a healthy person of a particular age, sex, weight, height, and physical activity.
Nutrition research employs the scientific method. Research design and consistency across studies are important determinants of the quality, reliability, and applicability of study findings.
Registered dietitian (RD) (also called RDNs—
Healthy People 2020 is a government-
The health and diets of Americans are monitored through government surveys like the National Health and Examination Survey (NHANES) that collects data about food and nutrient intake.
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Review Questions
Each of the six classes of nutrients:
provide energy for the body.
are essential for growth, development, and reproduction.
are required in similar quantities by the body.
can be produced by the body if dietary intake is inadequate.
1. b
2. All of the following are true regarding phytochemicals, EXCEPT:
they are classified as an essential micronutrient.
there are thousands of these compounds found in foods.
they are linked with reduced risk of cancer.
they are found primarily in plant foods.
2. a
3. Homeostasis can be defined as:
the process of digestion, absorption, and excretion of nutrients.
the interaction of nutrients resulting in reduced absorption and utilization.
the maintenance of a stable, internal environment in the face of external variability.
the balance and distribution of carbohydrate, protein, and fat intake in the overall diet.
3. c
4. Current nutrition research and policy focuses primarily on:
diseases of overconsumption.
nutrient deficiency diseases.
prevention of infectious diseases.
dietary supplements and herbs.
4. a
5. The focus of the RDA reference value:
is to only prevent deficiency diseases due to the prevalence of undernutrition.
is on nutritional supplements rather than food intake.
is to provide the amounts of nutrients required to restore health after major illness.
is to prevent deficiency diseases as well as reduce the risk of chronic diet-
5. d
6. All of the following are true regarding the Recommended Dietary Allowance (RDA), EXCEPT:
it represents the average amount of calories allowed for maintenance of a healthy body weight.
it represents the average daily amount of a nutrient that meets the needs of nearly all healthy individuals.
the nutrient requirement for most people is less than the RDA for individual nutrients.
it cannot be established if there is insufficient evidence to generate an EAR for that nutrient.
6. a
7. The Tolerable Upper Intake Level (UL) is defined as:
the optimal level of nutrient intake a person should consume each day.
the estimate of a safe daily level of nutrient intake that should not be exceeded.
the amount of excessive intake consumed from supplements and fortified foods.
the level at which calorie intake exceeds expenditure.
7. b
8. Randomized control trials encompass all of the following characteristics, EXCEPT:
they are retrospective in nature and classified as epidemiological studies.
they compare the effects of an intervention between experimental and control groups.
they randomly assign people to receive or not receive an intervention or treatment.
they may incorporate a placebo to avoid the expectation of results, or placebo effect.
8. a
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9. The name of the professional organizationof registered dietitians in the United Statesis the:
American Association of Dietitians and Nutritionists.
Academy of Nutrition and Dietetics.
American College of Dietetic Professionals.
National Food and Nutrition Association.
9. b
10. Healthy People 2020 is:
an ongoing government survey that collects data on the intake and eating patterns of Americans.
a public school-
a government-
a corporate and consumer partnership aimed at improving the healthfulness of commercial food products.
10. c
Take It Further
What are three specific ways you can evaluate the credibility and scientific validity of nutrition information or claims in the media or on the Internet?
Get Ready to Track Your Diet!
In this first SuperTracker exercise you will get familiar with the MyPlate component of the SuperTracker tool.
1. Log onto the United States Department of Agriculture (USDA) website at www.choosemyplate.gov. On the top of the home page, you will see the heading “SuperTracker and Other Tools.” Click this link.
2. You will need to create a profile for yourself to get a personalized diet plan. This profile will allow you to save your information and diet intake for future reference. You will be using the SuperTracker tool for the assignments in each of the chapters so choose a user name and password that will be easy for you to remember.
3. Return to the home page and click on the MyPlate link.
4. Click on the fruits category.
5. Click on the vegetables group.
6. Click on the grains group.
7. Click on the protein group.
8.Click on the dairy group.
9. Click on the oils group.
What is the Key Consumer Message for the fruits group?
What is the Key Consumer Message for vegetables group?
What is the Key Consumer Message for grains group? List two examples of whole grain foods and two examples of refined grain foods.
List two examples of animal sources of protein and two examples of plant sources of protein.
What is the Key Consumer Message for the dairy group?
According to SuperTracker, what is the difference between oils and fats? List two examples of oils. List two foods that are naturally high in oils.