1. Chapter 1 What You Eat and Why? Lecture Outline Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display

2. Chapter 1: What You Eat and Why?

3. What is Nutrition?

4. N utrition is “the science of food, the nutrients and the substances therein, their action, interaction, and balance in relation to health and disease, and the process by which the organism ingests, absorbs, transport, utilizes, and excretes food substances”---- The Council on Food and Nutrition of the American Medical Association “the science of food, the nutrients and the substances therein, their action, interaction, and balance in relation to health and disease, and the process by which the organism ingests, absorbs, transport, utilizes, and excretes food substances”---- The Council on Food and Nutrition of the American Medical Association

5. Nutrients Come from Food Provide energy Provide energy Provide building blocks Provide building blocks Vital for growth and maintenance Vital for growth and maintenance Essential Essential

6. Essential Nutrient Omission leads to decline Omission leads to decline Regain normal function when restored to the diet Regain normal function when restored to the diet Has specific biological function Has specific biological function

7. Why study nutrition?

8. Nutrition and Health Poor diet and sedentary lifestyle are risk factors for chronic diseases: Poor diet and sedentary lifestyle are risk factors for chronic diseases: –Disease of the heart (26.6% of all deaths) –Cancer (22.8%) –Cerebrovascular disease (5.9%) –Diabetes (3.1%) –Accounts for ~2/3 of all deaths

10. Maintain optimal health Maintain optimal health “Affliction of Affluence” “Affliction of Affluence” We are living longer We are living longer

11. The Six Classes of Nutrients Carbohydrates Carbohydrates Lipids Lipids Proteins Proteins Vitamins Vitamins Minerals Minerals Water Water

12. Nutrient Functional Categories Provide calories Provide calories For growth, development, and maintenance For growth, development, and maintenance Regulate body processes Regulate body processes

13. Carbohydrates Composed of carbon, hydrogen, oxygen Composed of carbon, hydrogen, oxygen Major source of fuel Major source of fuel Monosaccharide (glucose) Monosaccharide (glucose) Simple and complex forms Simple and complex forms Dietary fiber Dietary fiber Energy yielding (~4 kcal /gm) Energy yielding (~4 kcal /gm)

14. Lipids Composed of carbon, hydrogen, fewer oxygen Composed of carbon, hydrogen, fewer oxygen Triglycerides Triglycerides –Fats and oils Unsaturated Fatty Acids Unsaturated Fatty Acids Saturated Fatty Acids Saturated Fatty Acids Essential Fatty Acids Essential Fatty Acids Energy yielding fats and oils (~9 kcal /gm) Energy yielding fats and oils (~9 kcal /gm) Cholesterol Cholesterol Phospholipids Phospholipids

15. Proteins Composed of carbon, hydrogen, oxygen, nitrogen Composed of carbon, hydrogen, oxygen, nitrogen Structural material Structural material (9) Essential amino acids (9) Essential amino acids (11) Nonessential amino acids (11) Nonessential amino acids Energy yielding (~4 kcal /gm) Energy yielding (~4 kcal /gm) Excess protein intake Excess protein intake

16. Vitamins Composed of various elements Composed of various elements Enable chemical reactions Enable chemical reactions Fat soluble Fat soluble Water soluble Water soluble Yield no energy Yield no energy

17. Minerals Inorganic substances Inorganic substances Function in cellular processes, nervous system, water balance, structural systems Function in cellular processes, nervous system, water balance, structural systems Not destroyed during cooking Not destroyed during cooking Trace minerals Trace minerals Major minerals Major minerals Electrolytes Electrolytes Yield no energy Yield no energy

18. Water Composed of hydrogen, oxygen Composed of hydrogen, oxygen Majority of our body weight Majority of our body weight Found in foods Found in foods Yields no energy Yields no energy Recommended intake Recommended intake –9-13 cups/day Functions: Functions: –Solvent, lubricant, medium for transport, chemical processes, and temperature regulator

20. Phytochemicals A chemical found in plants A chemical found in plants –Not considered essential nutrients –Provide significant health benefits –Found in fruits and vegetables

22. Composition

23. Transformation of Energy Carbohydrate Protein Fat Alcohol 4 kcal/gm 4 kcal/gm 9 kcal/gm 7 kcal/gm ENERGY SOURCES Build new compounds Muscular movement Nerve transmission Ion balance

24. What is a Calorie? Measurement of energy Measurement of energy “The amount of heat it takes to raise the temperature of 1 gram of water by 1 degree Celsius” “The amount of heat it takes to raise the temperature of 1 gram of water by 1 degree Celsius” 1,000 calories = 1 kcal = 1(food) Calorie 1,000 calories = 1 kcal = 1(food) Calorie

25. Sample Calculation of a Nutrition Label Per serving Per serving –Carbohydrate: 15g x 4 kcal/g = 60 kcal –PRO: 3g x 4 kcal/g = 12 kcal –FAT: 1g x 9 kcal/g = 9 kcal –TOTAL: 81 kcal, rounded down to 80

26. Contribution to Total kcal One day’s intake (1980 kcal) One day’s intake (1980 kcal) 290 gm of carbohydrate (x 4 kcal/gm) 290 gm of carbohydrate (x 4 kcal/gm) 60 gm of fat (x 9 kcal/gm) 60 gm of fat (x 9 kcal/gm) 70 gm of protein (x 4 kcal/gm) 70 gm of protein (x 4 kcal/gm) % of kcal as carbohydrate = (290 x 4)/1980 = 0.59 or 59% % of kcal as carbohydrate = (290 x 4)/1980 = 0.59 or 59% % of kcal as Fat= (60 x 9)/1980 = 0.27 or 27% % of kcal as Fat= (60 x 9)/1980 = 0.27 or 27% % of kcal as PRO= (70 x 4)/1980 = 0.14 or 14% % of kcal as PRO= (70 x 4)/1980 = 0.14 or 14%

27. The Typical American Diet 16% of kcal as proteins 16% of kcal as proteins –~66% from animal sources –10-35% advised 50% of kcal as carbohydrate 50% of kcal as carbohydrate –~50% from simple sugars –45-65% advised 33% of kcal as fat 33% of kcal as fat –~60 % from animal fats –20-35% advised

28. Assessing Our Diets National Health and Nutrition Examination Survey (NHANES) [US Dept. of Health & Human Services] National Health and Nutrition Examination Survey (NHANES) [US Dept. of Health & Human Services]

29. Improving Our Diets Monitor energy intake Monitor energy intake Salt (sodium) in moderation Salt (sodium) in moderation Alcohol in moderation Alcohol in moderation Fat in moderation Fat in moderation Adequate fluids Adequate fluids Eat 5-A-Day Eat 5-A-Day Use supplements wisely, if at all Use supplements wisely, if at all Mealtime is a social time Mealtime is a social time

30. Healthy People 2010 www.healthypeople.gov Promote healthy lifestyle Promote healthy lifestyle Reduce preventable deaths and diseases Reduce preventable deaths and diseases Reduce obesity in adults and children Reduce obesity in adults and children Increase intake of fruits, vegetables, and whole grain products Increase intake of fruits, vegetables, and whole grain products Lower intake of fat, saturated fats, and sodium Lower intake of fat, saturated fats, and sodium Increase intake of calcium and iron Increase intake of calcium and iron

32. Why Am I So Hungry? Hunger Hunger –Physical biological drive Appetite Appetite –Psychological drive

33. Satiety Regulated by the hypothalamus Regulated by the hypothalamus Feeding center Feeding center Satiety center Satiety center Meal size and composition Meal size and composition Macronutrients in the blood Macronutrients in the blood Hormones Hormones

35. Eating Well in College Freshman Fifteen Freshman Fifteen –Stressful situations –University environment –Peer pressure –Alcohol –Lack of Exercise

36. Eating Well in College Tips to avoid the freshmen fifteen Tips to avoid the freshmen fifteen –Eat breakfast –Plan ahead –Limit liquid calories –Stock the fridge with healthy choices –Exercise regularly