2. Introduction to Human Nutrition Course Web Page Course Web Page

3. Real Hope for Haiti – Clinic for Malnourished Children

4. Chapter Outline  Nutrition defined  Classifying the nutrients  Nutritional research –  Nutritional research – now in CH 2  Nutrition and health Healthy People 2020 goals Healthy People 2020 goals  Factors impacting food choices Small group exercise Small group exercise

5.  intake that allows you to function at your best and promotes health.  Quality intake that allows you to function at your best and promotes health. Intake that provides adequate levels of each nutrient Intake that provides adequate levels of each nutrient  of intake that promotes a healthy body weight.  Quantity of intake that promotes a healthy body weight. Nutritional Goals

6. Nutrition Defined  Nutrition – the science of foods and the nutrients they contain  Study the: action of foods and the nutrients in the body action of foods and the nutrients in the body relationship between diet and health relationship between diet and health

7. Nutrition Defined  Actions in the body include: Ingestion Ingestion Digestion Digestion Absorption Absorption Transport Transport Metabolism Metabolism Excretion Excretion

8. What’s Considered Food?  Foods contain nutrients and are derived from plant or animal sources  Nutrients are used by the body to provide energy and to support growth, maintenance and repair of body tissues ~ 40 nutrients identified at this time ~ 40 nutrients identified at this time

9. Classifying Nutrients (1.3) There are 6 Classes of Nutrients 1. Carbohydrates 2. Lipids (fats) 3. Proteins 4. Vitamins 5. Minerals 6. Water

10. Body Composition

11. Describing the Nutrients  There are several ways to classify the classes of nutrients. Essential or nonessential Essential or nonessential Organic or inorganic Organic or inorganic Macronutrient or micronutrient Macronutrient or micronutrient Energy yielding or not Energy yielding or not

12. Classifying Nutrients  Essential nutrients – nutrients the body either cannot make or cannot make enough of to meet its needs. These nutrients must be obtained from foods (ingested in some manner) These nutrients must be obtained from foods (ingested in some manner) Examples: Examples: VitaminsVitamins Calcium, iron, and other mineralsCalcium, iron, and other minerals Some of the amino acidsSome of the amino acids

13. Essential Nutrients  To be classified as an essential nutrient: The biological function of nutrient is known The biological function of nutrient is known Omission from the diet leads to a decline in a biological function Omission from the diet leads to a decline in a biological function Return of the nutrient restores the biological function Return of the nutrient restores the biological function

14. Classifying Nutrients  Nonessential nutrients – body can make from other nutrients ingested  Examples: CholesterolCholesterol Some amino acidsSome amino acids

15. Classifying Nutrients by Composition  Organic nutrients - contain carbon CarbohydratesCarbohydrates LipidsLipids ProteinsProteins VitaminsVitamins  Inorganic nutrients - do not contain carbon MineralsMinerals Water Water

16. Quantity Needed  Macronutrients: need in relatively large amounts Carbohydrates, lipids, proteins Carbohydrates, lipids, proteins  Micronutrients: need in relatively small amounts All other nutrients All other nutrients

17. Classifying Nutrients  Energy-yielding nutrients (3): Carbohydrates Carbohydrates Fats (lipids) Fats (lipids) Proteins Proteins  Where does the energy come from?

18. A little more on energy  Measure energy in kilocalories in U.S. What most think of as a “calorie” is really a kilocalorie What most think of as a “calorie” is really a kilocalorie Kcal = amount of energy needed to raise the temperature of 1 kg of water by 1 0 C Kcal = amount of energy needed to raise the temperature of 1 kg of water by 1 0 C  Measure energy in kilojoules (kJ) in most other countries

19. Energy in the Body  The body uses the energy yielding nutrients to fuel all activities All energy yielding nutrients are “caloric”. All energy yielding nutrients are “caloric”.  If more energy is ingested than is needed to fuel body activities the extra energy is stored as _________ and ________ occurs.

20. Energy-Yielding Nutrients

21.  Carbohydrates: C, H, O 4 kcal/gram 4 kcal/gram Body’s primary source of energy Body’s primary source of energy Use as glucoseUse as glucose Glucose is the brain’s only source of energyGlucose is the brain’s only source of energy Carbohydrate stores are limited ~12-24 hours (in liver and muscle) Carbohydrate stores are limited ~12-24 hours (in liver and muscle)

22. Classes of Carbohydrates  Simple sugars Monosaccharides and disaccharides Monosaccharides and disaccharides  Complex carbohydrates Starch Starch Fibers Fibers  Carbohydrate rich foods……..

23. Lipids  Lipids – fats and oils: C, H, O 9 kcal/gram 9 kcal/gram Body’s alternate source of energy Body’s alternate source of energy Use fat along with glucose as an energy source most of the timeUse fat along with glucose as an energy source most of the time Stores are unlimited Stores are unlimited

24. Types of Lipids  Fats – solids  Oils – liquids  Saturated (solids/fats) No carbon to carbon double bonds No carbon to carbon double bonds  Unsaturated (liquids/oils) Carbon to carbon double bond(s) present Carbon to carbon double bond(s) present  Lipid rich foods?

25. Proteins  Proteins: C, H, O, N, S 4 kcal/gram (same as _______) 4 kcal/gram (same as _______) Body’s least desirable source of energy Body’s least desirable source of energy WHY? …….WHY? ……. Protein is used for energy only when carbohydrate is NOT available as an energy source. Protein is used for energy only when carbohydrate is NOT available as an energy source. Protein rich foods? Protein rich foods?

26. Energy-Yielding Non-nutrient  Alcohol – 7 kcal/gram  Non-nutrient because it interferes with growth, maintenance and repair of the body Alcohol’s metabolites are harmful Alcohol’s metabolites are harmful No required functions in the body No required functions in the body

27. Energy Density  Measure of the kcal per gram of food  _______ has the highest energy density of the 3 energy-yielding nutrients.  Foods with a high energy density provide more kcal per gram than low density foods.

28. Energy Density

29. Evaluating a Food Label  _____ grams carbohydrate  _____ grams fat  _____ grams protein  TOTAL KCAL: ____________

30. 6 Classes of Nutrients Carbohydrates Carbohydrates Lipids (fats and oils) Lipids (fats and oils) Proteins Proteins Vitamins Vitamins Minerals Minerals Water Water

31. Vitamins  Essential  Organic, micronutrient  Not energy-yielding  Can be water-soluble or fat-soluble Examples:

32. Minerals  Essential  Inorganic, micronutrient Major minerals: Ca, P, Na Major minerals: Ca, P, Na Trace minerals: Fe, Zn Trace minerals: Fe, Zn  Not energy-yielding  Indestructible

33. Water  Water (H 2 O) Essential Essential Organic or inorganic? Organic or inorganic? Noncaloric Noncaloric We are ~60% water We are ~60% water

34. Not everyone has access to clean water

35. The Science of Nutrition  One of the newest sciences New branch is nutritional genomics New branch is nutritional genomics Study of the interaction of nutrients with DNA/genes and how those genes impact healthStudy of the interaction of nutrients with DNA/genes and how those genes impact health  Like all sciences, nutrition is based on scientific research  Skip to slide 53 – Nutrition and health

37. Scientific Method 1. Observations  Questions 2. Hypotheses  Predictions 3. Test hypotheses/predictions 4. Analyze data and draw conclusions 5. Share results

38. Observations and Questions  Make observations about diet and health. These observations lead to questions For example: The incidence of breast cancer is much lower in Japan than in the U.S. The incidence of breast cancer is much lower in Japan than in the U.S. Diet in Japan is rich in…..while in U.S. diet is rich in …… Diet in Japan is rich in…..while in U.S. diet is rich in ……  Question?:

39. Develop Hypotheses and Make Predictions  Hypothesis – tentative explanation of the observations or answer to the question  Make prediction – If the hypothesis is true what else is true?

40. Experiments  Conduct experiments to test the predictions Easier said than done when people are involved! Easier said than done when people are involved! We’ll consider research designs later/soon. We’ll consider research designs later/soon.

41. One Experimental Design  When possible, randomly assign subjects to either a control of experimental group Goal is for two groups to be as similar to each other as possible Goal is for two groups to be as similar to each other as possible Control Group – either no change to diet or given a placebo Control Group – either no change to diet or given a placebo Experimental group – diet changed or given a supplement Experimental group – diet changed or given a supplement

42. Experimental Design  Compare the health/lab values of the two groups before and after the diet change. Example – DASH diet study Example – DASH diet study

43. Analyze results…  Analyze results  Draw conclusions about the validity of the hypothesis  Test alternate hypotheses  Share findings Publish in nutritional journals Publish in nutritional journals Present findings at conferences Present findings at conferences

44. Common Research Designs 1. Epidemiological study (observe) Cross-sectional Cross-sectional Longitudinal Longitudinal Case-control study Case-control study 2. Experimental (intervene) Animal studies Animal studies Human clinical trials Human clinical trials Double blind studyDouble blind study Lab studies Lab studies

45. The Science of Nutrition 1. Epidemiological studies Study of populationsStudy of populations Look for correlations between dietary practices and healthLook for correlations between dietary practices and health Nurses Health StudyNurses Health StudyNurses

46. Epidemiological Studies Cross-sectional - look for correlations between diet and health at a point in time Longitudinal Studies - Follow a group of people (a cohort) over a period of time Look for differences in diet that might account for the differences in healthLook for differences in diet that might account for the differences in health

47. Epidemiological Studies  Case-control study – compare the diet of individuals with a condition to that of healthy individuals Again, do not change their diet…..just observe it. Again, do not change their diet…..just observe it.

48. Human Experimental Studies Often called a Clinical Study Randomly assign like people to either the experimental or control groupRandomly assign like people to either the experimental or control group Alter the diet of experimental group as compared to a control groupAlter the diet of experimental group as compared to a control group Compare incidence of disease/lab values/ performance …. of two groupsCompare incidence of disease/lab values/ performance …. of two groups

49. Types of Clinical Trials  Blind experiments Subjects do not know which group they are inSubjects do not know which group they are in  Double blind experiments Neither subjects nor the researchers know which group the subjects are in until after the experiment is overNeither subjects nor the researchers know which group the subjects are in until after the experiment is over Goal is to avoid bias in the reporting/recording of the data.Goal is to avoid bias in the reporting/recording of the data.

50. Experimental Studies Animal Studies Controlled studies in lab setting using animalsControlled studies in lab setting using animals Alter diet of experimental groupAlter diet of experimental group Compare health/lab values of control and experimental groupsCompare health/lab values of control and experimental groups Benefits? ….Benefits? …. Drawbacks? ……Drawbacks? ……

51. Experimental Studies Lab-Based Studies Also called in vitro studiesAlso called in vitro studies Examine impact of a substance on living tissue in a “test tube”Examine impact of a substance on living tissue in a “test tube”-------------------------------------------------------------

53. The Science of Nutrition  Size matters Good studies have relatively large sample sizes Good studies have relatively large sample sizes Preliminary studies have smaller sample sizes Preliminary studies have smaller sample sizes  Peer review matters Information in peer- reviewed research journals is much more credible than that in popular magazines, TV, Internet Information in peer- reviewed research journals is much more credible than that in popular magazines, TV, Internet

54. Diet and Health  Diet - the foods one consumes The quality of your daily diet affects the risk of chronic diseasesThe quality of your daily diet affects the risk of chronic diseases Meaning…..The food choices you make daily have a cumulative impact on your health Meaning…..The food choices you make daily have a cumulative impact on your health

55. Nutrition and Health  Chronic health issues associated with diet include: Heart disease Heart disease Hypertension Hypertension Obesity Obesity Type II Diabetes Type II Diabetes Osteoporosis Osteoporosis

56. Improving your Health  Goal is to reduce the number of risk factors that are in your control Risk factor = something that statistically increases the incidence of a disease Risk factor = something that statistically increases the incidence of a disease Risk factors may not be the cause of the diseaseRisk factors may not be the cause of the disease

57. Leading Causes Death Leading Causes Death - US Leading Causes Death 1. Heart disease: 616,067 2. Cancer: 562,875 3. Stroke: 135,952 4. Chronic respiratory diseases: 127,924 5. Accidents (unintentional injuries): 123,706 6. Alzheimer's disease: 74,632 7. Diabetes: 71,382 8. Influenza and Pneumonia: 52,717 9. Kidney disease: 46,448 10. Septicemia: 34,828 CDC, 2009

58. Leading Causes Death Leading Causes Death - US Leading Causes Death 1. 1. Heart disease: 596,577 2. 2. Cancer: 576,691 3. 3. Chronic lower respiratory diseases: 142,943 4. 4. Stroke (cerebrovascular diseases): 128,932 5. 5. Accidents (unintentional injuries): 126,438 6. 6. Alzheimer's disease: 84,974 7. 7. Diabetes: 73,831 8. 8. Influenza and Pneumonia: 53,826 9. 9. Kidney disease: 45,591 10. 10. Intentional self-harm (suicide): 39,518 CDC, 2010 data CDC, 2010 data

59. Improving Health  Risk factors in your control: Smoking Smoking Alcohol intake Alcohol intake Over-consumption of calories Over-consumption of calories Physical inactivity Physical inactivity Poor quality diet Poor quality diet

60. Improving Health  Risk factors you cannot control: Age Age Gender Gender Genetics (family history) Genetics (family history) Ethnicity Ethnicity

61. Maine Data   27% report NO physical activity 1 in 5 engage in moderate physical activity ~5 days/week   74% do NOT eat 5 servings of fruits and vegetables daily   28.9% of Maine adults are obese (2013)

62. Healthy People 2020 Healthy People 2020  Americans with a healthful diet: Consume a variety of nutrient-dense foods within and across the food groups, especially: Consume a variety of nutrient-dense foods within and across the food groups, especially: whole grains, fruits, vegetables, low-fat or fat-free milk or milk products, and lean meats and other protein sources.whole grains, fruits, vegetables, low-fat or fat-free milk or milk products, and lean meats and other protein sources. Limit the intake of saturated and trans fats, cholesterol, added sugars, sodium (salt), and alcohol. Limit the intake of saturated and trans fats, cholesterol, added sugars, sodium (salt), and alcohol.

63. Healthy People 2020  Limit caloric intake to meet caloric needs. All Americans should avoid unhealthy weight gain, and those whose weight is too high may also need to lose weight All Americans should avoid unhealthy weight gain, and those whose weight is too high may also need to lose weight

64. Food Choices  Small group exercise What influences your food choices each day? What influences your food choices each day? Why do you eat what you eat? Why do you eat what you eat? Get into groups of ~4 and make a list of what impacts your food choices most days. Get into groups of ~4 and make a list of what impacts your food choices most days. Turn this list in next time we meet.Turn this list in next time we meet.

65. Food Choices – Text Answers 1. Personal preferences 2. Habit 3. Ethnic heritage 4. Tradition 5. Social interactions or pressure 6. Availability 7. Convenience 8. Economy $ 9. Positive or negative associations 10. Emotional Comfort 11. Values - Religious, political, environmental 12. Health concerns 13. Nutritional value