1. An Overview of Nutrition
Chapter 1

2. Introduction Daily food choices Diet Benefit health Harm health
Chronic disease
Diet
Foods and beverages

3. Food Choices Are Highly Personal
Personal preference
Taste: sweet and salty, genetics
Habit
Ethnic heritage or tradition
Social interactions
Availability, convenience, and economy
Benefits of home-cooked meals
Positive and negative associations

4. Food Choices – Other Factors
Emotions
Boredom, depression, anxiety
Stress
Values
Religious beliefs, political views, environmental concerns
Body weight and image
Nutrition and health benefits
Functional and fortified foods

5. The Nutrients Water Minerals Vitamins Carbohydrates Proteins
Hydrogen & oxygen
Inorganic (no carbon)
Minerals
Simplest nutrient
Inorganic
Vitamins
Organic (contains carbon)
Carbohydrates
Organic
Proteins
Contains nitrogen
Lipids (fats)

6. Body Composition of Healthy-Weight Men and Women
Figure 1-1 Body composition of healthy-weight men and women

7. The Six Classes of Nutrients
Organic
Inorganic
Energy-yielding
Macronutrient
Micronutrient
Carbohydrates ✓
Lipids (fats)
Proteins
Vitamins
Minerals
Water
Table 1-1 The six classes of nutrients

8. Macronutrients and Micronutrients
Macronutrients yield energy
Carbohydrate
Fat
Protein
Water and minerals do not yield energy
Micronutrients
Vitamins and minerals
Human body needs small amounts

9. Energy-Yielding Nutrients
Macronutrients: source of kcalories
Carbohydrate = 4 kcal/g
Protein = 4 kcal/g
Fat = 9 kcal/g
Higher energy density
Alcohol
Not a nutrient
Yields energy – 7 kcal/g
Lower energy density foods
Contribute to weight loss

10. Energy in the Body Body uses macronutrients
Bonds between the nutrients’ atoms break
Energy is released
Can then be used or stored
Macronutrients
Provide raw material for building tissue and regulating body activities
Proteins regulate digestion and energy metabolism

11. The Vitamins Thirteen organic vitamins Facilitate energy release
Each has a special role to play
Facilitate energy release
Almost every bodily action requires assistance from vitamins
Vulnerable to destruction
Heat (as from cooking), light, and chemicals

12. The Minerals and Water Minerals Water Do not yield energy
Sixteen essential minerals
Other minerals are environmental contaminants
Example: lead
Indestructible
But can be lost into cooking water, for example
Water
Environment for nearly all body processes

13. The Science of Nutrition
Foundation in several other sciences
Biology, biochemistry, physiology
Tremendous growth
Knowledge gained from sequencing the human genome
Nutritional genomics

14. Conducting Research Use of scientific method Research studies
Systematic process for conducting research
Research studies
Controls
Randomization
Sample size
Placebos
Double-blind experiments

15. The Scientific Method

16. Design a study and conduct the research to collect relevant data
Identify a problem to be solved or ask a specific question to be answered
OBSERVATION & QUESTION
HYPOTHESIS & PREDICTION
Formulate a hypothesis—a tentative solution to the problem or answer to the question—and make a prediction that can
be tested
EXPERIMENT
Design a study and conduct the research to collect relevant data
RESULTS & INTERPRETATIONS
Summarize, analyze, and interpret the data; draw conclusions.
Figure 1-3 The Scientific Method Research scientists follow the scientific method. Note that most research generates new questions, not final answers. Thus the sequence begins anew, and research continues in a somewhat cyclical way.
HYPOTHESIS SUPPORTED
HYPOTHESIS NOT SUPPORTED
NEW OBSERVATIONS & QUESTIONS
THEORY
Develop a theory that integrates conclusions with those from numerous other studies
Stepped Art

17. Types of Research Epidemiological studies Experimental studies
Cross-sectional studies
Case-control studies
Cohort studies
Experimental studies
Laboratory-based animal studies
Laboratory-based in vitro studies
Human intervention (clinical) trials

18. Examples of Epidemiological Studies

19. Examples of Experimental Studies

20. Analyzing Research Findings
Correlations – only show association
Positive correlation
Not necessarily a desired outcome
Negative correlation
No correlation
Cautious interpretations and conclusions
Accumulation of evidence

21. Publishing Research Peer review
Research has validity
Findings are preliminary when published
Not meaningful by themselves
Findings need to be replicated

22. Parts of a Research Article
• Abstract. The abstract provides a brief overview of the article. • Introduction. The introduction clearly states the purpose of the current study and provides a comprehensive review of the relevant literature. • Review of literature. A comprehensive review of the literature reveals all that science has uncovered on the subject to date. • Methodology. The methodology section defines key terms and describes the study design, subjects, and procedures used in conducting the study. • Results. The results report the findings and may include tables and figures that summarize the information. • Discussion: The discussion draws tentative conclusions that are supported by the data and reflect the original purpose as stated in the introduction. Usually, it answers a few questions and raises several more. • References. The references reflect the investigator's knowledge of the subject and should include an extensive list of relevant studies (including key studies several years old as well as current ones).
Table 1-3 Parts of a research article

23. Dietary Reference Intakes
Standards defined for:
Energy
Nutrients
Other dietary components
Physical activity
Collaborative effort between United States and Canada
Recommendations apply to healthy people
May be different for specific groups

24. EAR and RDA Estimated Average Requirements (EAR)
Average amount sufficient for half of population
Recommended Dietary Allowances (RDA)
Recommendations to meet needs of most healthy people
Set near the top end of the range of EAR

25. EAR and RDA Compared

26. Adequate Intakes and Upper Intake Levels
Adequate Intakes (AI)
Insufficient scientific evidence to establish EAR
AI value set instead of RDA
Expected to exceed average requirements
Tolerable Upper Intake Levels (UL)
Point where nutrient is likely to be toxic
Helps protect against overconsumption

27. Inaccurate versus Accurate View of Nutrient Intakes
If a person’s usual intake falls above the RDA, the intake is probably adequate because the RDA meets the needs of almost all people.
A usual intake that falls between the RDA and the EAR is more difficult to assess; the intake may be adequate, but the chances are greater or equal that it is inadequate.
If the usual intake falls below the EAR, it is probably inadequate.
Figure 1-6 Inaccurate versus accurate view of nutrient intakes

28. Establishing Energy Recommendations
Estimated Energy Requirement (EER)
Average dietary energy intake to maintain energy balance
Healthy body weight
Physical activity
No upper level

29. Acceptable Macronutrient Distribution Ranges (AMDR)
Adequate energy and nutrients
Reduce risk of chronic diseases
Ranges
45-65% kcalories from carbohydrate
20-35% kcalories from fat
10-35% kcalories from protein

30. Using Nutrient Recommendations
Estimates apply to healthy people
Needs adjusting for medical problems, malnourishment, or other condition
Recommendations – not minimum levels nor optimal levels
Goals intended to be met through diet
Apply to average daily intakes
Each DRI category serves a unique purpose

31. Nutrition Assessment
Deficiency or excess over time leads to malnutrition
Undernutrition and overnutrition
Symptoms of malnutrition
Diarrhea
Skin rashes
Fatigue
Others

32. Creating a “Total Picture” of the Individual
Historical information
Health status, SES, drug use
Diet history – intake over several days; portion sizes; computer analysis
Anthropometric measurements
Height and weight – track to identify trends
Physical examinations
Laboratory tests

33. Stages in the Development of a Nutrient Deficiency
Figure 1-7 Stages in the development of a nutrient deficiency

34. Nutrition Assessment of Populations
National nutrition surveys
Conducted by various agencies
One survey collects data on food types and amounts
Another collects data about people themselves
Oversample high-risk groups
National health goals
Healthy People program
National trends

35. Healthy People 2020 Nutrition and Weight Status Objectives
Increase the proportion of adults who are at a healthy weight
Reduce the proportion of adults who are obese
Reduce iron deficiency among young children and females of childbearing age
Reduce iron deficiency among pregnant females
Reduce the proportion of children and adolescents who are overweight or obese
Increase the contribution of fruits to the diets of the population aged 2 years and older
Increase the variety and contribution of vegetables to the diets of the population aged 2 years and older
Increase the contribution of whole grains to the diets of the population aged 2 years and older
Reduce consumption of saturated fat in the population aged 2 years and older
Reduce consumption of sodium in the population aged 2 years and older
Increase consumption of calcium in the population aged 2 years and older
Increase the proportion of worksites that offer nutrition or weight management classes or counseling
Table 1-4 Healthy people 2020 nutrition and weight status objectives (continues)

36. Healthy Weight Objectives (Cont’d.)
Increase the proportion of physician office visits that include counseling or education related to nutrition or weight
Eliminate very low food security among children in US households
Prevent inappropriate weight gain in youth and adults
Increase the proportion of primary care physicians who regularly measure the body mass index of their patients
Reduce consumption of kcalories from solid fats and added sugars in the population aged 2 years and older
Increase the number of states that have state-level policies that incentivize food retail outlets to provide foods that are encouraged by the Dietary Guidelines
Increase the number of states with nutrition standards for foods and beverages provided to preschool-aged children in childcare
Increase the percentage of schools that offer nutritious foods and beverages outside of school meals
NOTE: Nutrition and Weight Status is one of 38 topic areas, each with numerous objectives. Several of the other topic areas have nutrition-related objectives, and these are presented in Appendix J.
SOURCE:
Table 1-4 Healthy people 2020 nutrition and weight status objectives (cont’d.)

37. Diet and Health Food plays vital role in supporting health
Percentage of Total Deaths
1. Heart disease
23.7
2. Cancers
22.9
3. Chronic lung diseases
5.7
4. Strokes
5.1
5. Accidents
4.9
6. Alzheimer's disease
3.4
7. Diabetes mellitus
2.9
8. Pneumonia and influenza
2.1
9. Kidney disease
1.8
10. Suicide
1.5
Food plays vital role in supporting health
Chronic disease – epidemic levels
Multiple factors over multiple years
Table 1-5 Leading causes of death in the United States
NOTE: The diseases highlighted in bold have relationships with diet SOURCE: Deaths: Preliminary data for 2011, National Vital Statistics Reports. October 10, Centers for Disease Control and Prevention,

38. Chronic Disease Risk Factors
Percentage of Deaths
Tobacco 18
Poor diet/inactivity 15
Alcohol 4
Microbial agents 3
Toxic agents 2
Motor vehicles
Firearms 1
Sexual behavior
<1
Illicit drugs
Risk factors
Persist over time
Cluster
Prominence of risk factors
Tobacco
Diet and activity patterns
Others
Table 1-6 Factors contributing to deaths in the United States
SOURCE: A. H. Mokdad and coauthors, Actual causes of death in the United States Journal of the American Medical Association 291 (2004): , with corrections from Journal of the American Medical Association 293 (2005): 298.

39. Nutrition Information and Misinformation
Highlight 1

40. Nutrition on the Internet
Validity of information
Who is providing information?
Qualifications
Internet
Anyone can publish anything
No guarantees of accuracy
Evaluate websites
Who, when, where, why, and what?

41. Nutrition in the News News often tells lopsided story Testimonials
Tight deadlines
Limited understanding
Current and controversial

42. Identifying Nutrition Experts
Physicians and other health-care professionals
Training in nutrition is limited
Registered dietitian (RD)
Degree and clinical internship
National exam
Maintain up-to-date knowledge
Dietetic technician registered (DTR)

43. Credentials Identifying fake credentials
College accreditation
Diploma mills
Fraudulent businesses
Red flags of nutrition quackery
Misinformation
Consider the source
Buyer beware

44. Red Flags of Nutrition Quackery
Figure H1-2 Red flags of nutrition quackery