The Role of Nutrition in Our Health

1. The Role of Nutrition in Our Health Chapter 1

2. Test Yourself • A calorie is a measure of the amount of fat in a food. • Proteins are not a primary source of energy for our bodies. • All vitamins must be consumed daily to support optimal health. • The Recommended Dietary Allowance is the maximum amount of a nutrient that people should consume to support normal body functions. T F T F T F T F

3. What is Nutrition? • Nutrition is a relatively new discipline of science. • Nutrition: the study of food, including • How food nourishes our bodies • How food influences our health Digestion Absorption Utilization Excretion

4. How Does Nutrition Contribute to Health? • Nutrition contributes to wellness. • Wellness: more than absence of disease • Many factors contribute to an individual’s wellness. Primary among these are: • Nutrition • Physical activity

5. How Does Nutrition Contribute to Health? • Healthful diet is part of disease prevention

6. How Does Nutrition Contribute to Health?

7. How Does Nutrition Contribute to Health? • Nutrition is so important it has become a national goal to promote optimal health and disease prevention. • Goals of Healthy People 2020 – this is a health promotion and disease prevention plan for the United States. • Increase quality and years of healthy life • Eliminate health disparities

8. How Does Nutrition Contribute to Health? • Obesity is a growing problem in the U.S. • Note the states in dark “red” which indicates a prevalence of obesity >30%

9. What Are Nutrients? • Nutrients: chemicals in foods that our bodies use for energy and to support the growth, maintenance, and repair of our tissues. Six groups of nutrients: • Carbohydrates • Lipids • Proteins • Vitamins • Minerals • Water

10. What Are Nutrients? • Essential nutrients: nutrients for which specific biological functions have been identified, and which our bodies cannot make enough of to meet our biological needs • Essential nutrients must be obtained from our diet • Examples: Vitamin C, Calcium, Thiamin

11. What Are Nutrients? • Macronutrients: nutrients required in relatively large amounts. • Carbohydrates, lipids, proteins • Provide energy to our bodies • Micronutrients: nutrients required in smaller amounts. • Vitamins and minerals

12. What Are Nutrients? • Organic nutrients: nutrients contain an element of carbon that is an essential component of all living organisms • Carbohydrates, lipids, proteins, vitamins • Inorganic nutrients: nutrients that do not contain carbon • Minerals and water

13. Energy From Nutrients • We measure energy in kilocalories (kcal). • Kilocalorie: amount of energy required to raise the temperature of 1 kg of water by 1oC. • On food labels, “calorie” actually refers to kilocalories.

14. Carbohydrates • Primary source of fuel for the body, especially for the brain and physical activity. • Provide 4 kcalper gram. Carbohydrates are found in grains (wheat, rice), vegetables, fruits, and legumes (lentils, beans, peas), milk products.

15. Lipids - triglycerides, phospholipids, sterols • Insoluble in water. • Provide 9 kcal per gram. • An important energy source during rest or low intensity exercise. • Stored as adipose tissue (body fat) – major form of stored energy. • Foods containing lipids also provide fat-soluble vitamins and essential fatty acids.

16. Proteins • Proteins are chains of amino acids. • Support tissue growth, repair, and maintenance. • Proteins can supply 4 kcal of energy per gram, but are not a primary energy source. • Proteins are an important source of nitrogen.

17. Vitamins • Vitamins are organic molecules that assist in regulating body processes: • critical in building and maintaining healthy bones and tissues • support immune system • ensure healthy vision • Many can be destroyed by heat and oxidation • Vitamins do not supply energy to our bodies; however, many vitamins act as coenzymes for energy producing reactions

18. Vitamins

19. Minerals • Minerals are inorganic substances required for body processes. • Minerals have physiological functions, such as fluid regulation, energy production, bone structure, muscle movement, and nerve functioning.

20. Minerals • Our bodies require at least 100 mg per day of the major minerals such as: • Calcium • Phosphorus • Magnesium • Sodium • Potassium • Chloride. • We require less than 100 mg per day of the trace minerals such as: • Iron • Zinc • Copper • Selenium • Iodine • Fluoride

21. Water • Inorganic nutrient, essential for survival • Involved in many body processes: • fluid balance and nutrient transport • nerve impulses • body temperature • removal of wastes • muscle contractions • chemical reactions

22. Determining Nutrient Needs • Dietary Reference Intakes (DRIs): updated nutritional standards • Expand on the traditional RDA values • Set standards for nutrients that do not have RDA values • Dietary standards for healthy people only • For preventing deficiency diseases and reducing chronic diseases

23. Determining Nutrient Needs

24. Determining Nutrient Needs • Estimated Average Requirement (EAR) • The average daily intake level of a nutrient that will meet the needs of half of the healthy people in a particular category • Used to determine the Recommended Dietary Allowance (RDA) of a nutrient

25. Determining Nutrient Needs • Recommended Dietary Allowances (RDA) • The average daily intake level required to meet the needs of 97 – 98% of healthy people in a particular category

26. Determining Nutrient Needs • Adequate Intake (AI) • Recommended average daily intake level for a nutrient • Based on observations and experimentally determined estimates of nutrient intakes by healthy people • Used when the RDA is not yet established: calcium, vitamin D, vitamin K, fluoride

27. Determining Nutrient Needs • Tolerable Upper Intake Level (UL) • Highest average daily intake level likely to pose no risk of adverse health effects to most people • Consumption of a nutrient at levels above the UL, the potential for toxic effects and health risks increases

28. Determining Nutrient Needs • Example Nutrient DRI • Vitamin C (adult age 19-70) • UL = 2,000 mg/d • RDA = 75 mg/d (female) • 90 mg/d (male) • EAR = 60 mg/d (female) • 75 mg/d (male) • Amount needed to prevent • Deficiency = ~10 mg/d

29. Determining Nutrient Needs • Estimated Energy Requirement (EER) • Average dietary energy intake (kcal) to maintain energy balance in a healthy adult • Based on age, gender, weight, height, level of physical activity

30. Determining Nutrient Needs • Acceptable Macronutrient Distribution Ranges (AMDR) • Describes the portion of the energy intake that should come from each macronutrient • Carbohydrates: 45-65% • Fats: 20-35% • Proteins: 10-35% Potential for inadequate nutrient levels if nutrient intake falls below this range • Potential for increased chronic disease risk if nutrient intake falls above this range AMDR

31. Malnutrition • Nutritional status is out of balance:Individual is getting too much or too little of a particular nutrient or energy over a significant period of time • Undernutrition: too little energy or too few nutrients, causing weight loss or a nutrient deficiency disease • Overnutrition: too much energy or too much of a given nutrient over time, causing obesity, heart disease, or nutrient toxicity

32. Assessing Nutritional Status – A,B,C,D’s • A – Anthropometric Data • Weight, Height, Muscle Mass, Fat Mass • B – Biochemical Data • Cholesterol, Glucose, Albumin, Sodium, Liver Enzymes, Kidney Enzymes • C- Clinical Data • Disease history, Socioeconomic Status, Physical Exam • D – Dietary Data • Nutrient intake, supplement use

33. Dietary Intake Tools

34. Twenty-four Hour Recall • Recalls all food and beverages consumed in the previous 24-hour period • Accurate recall includes serving sizes, food preparation methods, and brand names of convenience foods or fast foods • Limitations: • may not be typical intake • rely on memory • ability to estimate portion sizes

35. Diet History • Information from interview or questionnaire: • Weight (current and usual weight, goals) • Factors affecting appetite and food intake • Typical eating pattern (time, place, dietary restrictions, frequency of eating out, etc.) • Disordered eating behaviors (if any) • Education and economic status • Living, cooking/food purchasing arrangements • Medication and dietary supplements • Physical activity

36. Food Frequency Questionnaires • Determine typical dietary pattern over a predefined period of time • Include lists of foods with the number of times these foods are eaten • Some assess only qualitative information (typical foods without amounts) • Semiquantitative questionnaires assess specific foods and quantity consumed

37. Diet Records • List of all foods and beverages consumed over a specific time period (3-7 days) • Kept by person seeking nutritional advice • More accurate with: • foods are weighted or measured • labels of convenience foods and supplements • People may change food intake to simplify record keeping • Analyses are time consuming and costly

38. Nutrition Deficiencies • Primary deficiencyoccurs when a person does not consume enough of a nutrient, a direct consequence of inadequate intake • Secondary deficiencyoccurs when… • a person cannot absorb enough of a nutrient in his or her body • too much nutrient is excreted from the body • a nutrient is not utilized efficiently by the body

39. Primary or Secondary Deficiency? Jane and John were both told by their primary care physicians that they had a type of anemia called “pernicious anemia” which is caused by a deficiency of vitamin B12 in the body. What type of deficiency do Jane and John have based on the evidence below? • Jane is a strict vegetarian and does not consume any animal-based foods and does not consume a vitamin/mineral supplements. • John consumes a regular diet consisting of all major food groups but has a condition called “gastritis” preventing his production of intrinsic factor, which is needed to help absorb vitamin B12

40. Deficiency Symptoms • Subclinical deficiency occurs in the early stages, few or no symptoms are observed • Covert symptoms are hidden and require laboratory tests or other invasive procedures to detect • Symptoms of nutrition deficiency that become obvious arereferred to asovert

41. Nutrition Deficiencies • What happens in the body: • Physical deficiency caused by inadequate diet OR secondary deficiency caused by problem inside the body • Declining nutrient stores • Abnormal functions inside the body • Physical (outward) signs and symptoms • Which assessment method reveals changes: • Diet history • Health history • Laboratory tests • Laboratory test • Physical examination and anthropometric measures

42. Registered Dietitians (RD) • Requirements: • Bachelor’s degree in nutrition • Completion of supervised clinical experience • Passing a national registration examination • Work in a variety of settings: • Hospitals, clinics, nursing homes • Sports nutrition • Food-service management • Community and public health nutrition • Nutrition research

43. Nutrition Advice: Who Can You Trust? • Nutrition is a new science • Increased interest in nutrition • Overwhelming amount of health claims • Reliability of nutrition information • Misinformation • Potential harmful quackery

44. Trustworthy Nutrition Experts • Registered Dietitian (RD) • Licensed Dietitian meets the credentialing requirements of a given state • Nutritionist has no legal definition • Professional with advanced nutrition degree (masters-MS, MA; doctoral-PhD) • Physician

45. Government Information Sources • Centers for Disease Control and Prevention (CDC) • National Health and Nutrition Examination Survey (NHANES) • Behavioral Risk Factor-Surveillance System (BRFSS) • National Institutes of Health (NIH)

46. Reliable Nutrition Information • American Dietetic Association • American Society for Nutrition Sciences • American Society for Clinical Nutrition • Society for Nutrition Education • American College of Sports Medicine • North American Association for the Study of Obesity

47. Evaluating Research • Case Control Studies • Clinical Trials • Randomized • Single Blind • Double Blind • Placebo

48. Evaluating Media Reports • Questions to ask? • Who conducted/paid for the research? • Who is reporting the information? • Is it based on reputable research studies? • Is the report based on testimonials? • Are the claims too good to be true? • Is someone profiting?

49. Activity

50. Calculate the Nutrition • Fat = 18 grams • Carbs = 6 grams • Protein = 7 grams • Total Calories: _________ • ____% Fat _____ % Carbs ______% Protein