nutrition

1. Chapter 3 nutrition

2. Test your knowledge • It is recommended that all adults consume 2 – 3 half – cup servings of fruits and vegetables every day. True or false? • FALSE. For someone consuming 2000 calories, 2 ½ cups of vegetables and 2 cups of fruit are recommended – a total of 9 half – cup servings.

3. Test your knowledge • Candy is the leading source of added sugars in the American Diet. True or False? • FALSE. Regular (nondiet) sodas are the leading source of added sugars and calories. • Each 12-ounce soda supplies about 10 teaspoons of sugar, or nearly 10% of the calories in a 2000 – calorie diet.

4. Test your knowledge • Which of the following is not a whole grain? • Brown rice • Wheat flour • Popcorn b. Unless labeled “whole wheat”, wheat flour is processed to remove the bran and germ and is not a whole grain.

5. Nutrition Requirements: Components of a healthy diet • 7 essential nutrients of a healthy diet • Protein • Fat (lipids) • Carbohydrates • Fiber • Water • Vitamins • Minerals Macronutrients Micronutrients

6. Energy in foods is expressed in kilocalories • 1 calorie = amount of heat needed to raise the temperature of 1 liter of water 1°C. • A person needs about 2000 kilocalories a day to meet energy needs. • Kilocalories are also known as calories, but 1 calorie = 1000 kilocalories. • Of the essential nutrients, three supply with energy: • Fat = 9 calories per gram • Protein = 4 calories per gram • Carbohydrate = 4 calories per gram. • Alcohol (not essential) = 7 calories per gram.

7. Nutrients are released into the body through the process of digestion

8. Proteins • Important part of the body’s muscles and bones • Also form part of blood, enzymes, cell membranes and some hormones. • Amino acids are the basic building block of proteins

9. Proteins • 20 amino acids are found in food • 9 of them are essential: hisidine, isoleucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. • The other 11 can be produced by the body.

10. Types: • Complete: if they supply all the essential amino acids • Incomplete: if they do not supply all the essential amino acids.

11. Recommended protein intake • 10 – 35% of total daily calories. • 0,8 gram per kilogram of body weight • 50 gr 140 pounds • 65 gr  180 pounds. • Problems of an excess protein intake • Excess protein is synthesized into fat • A very high protein intake can strain the kidneys and lead to dehydration

12. Fats • Stored in your body represent usable energy • Help to insulate the body • Provide support and cushion for organs • Help to absorb fat-soluble vitamins • Add flavor and texture to foods • Linoleic acid and alphalinoleic acid are essential to regulate blood pressure and progress of a healthy pregnancy.

13. Fats • Types: • triglycerides • Saturated solid Animal sources Hydrogenation • Unsaturated liquid Plant sources (linoleic – alpha-linoleic acids) • Monounsaturated • Polyunsaturated

14. Fats and health • Saturated fats • LDL (low density lipoprotein  bad cholesterol • Red meats, solid fats • Unsaturated fats • HDL (high density lipoprotein)  good chlolesterol • Avocados, nuts, olive and canola oil, fish (omega 3 fatty acids)

15. Recommended Fat Intake • Total fats should not exceed 20 – 30 % of the total calories. • 3 – 4 teaspoons of vegetable oil per day

16. Carbohydrates • Needed primarily to supply energy to body cells • Cells of the nervous system and blood use only energy from carbohydrates. • During intense exercise muscle cells get most of their energy from carbohydrates.

17. Carbohydrates • Types: • Simple • One or two sugar units in each molecule • Found naturally on fruits and milk • Sucrose, fructose, maltose, lactose • Complex • Long chains of sugar molecules • Found in tubers, fruits, vegetables and grains • Starches, dietary grains

18. Refined carbohydrates vs. whole grains • Whole grains • Consist of an inner layer of germ, a middle layer (endosperm) and an outer layer of bran. • Rich in nutrients • Refined carbohydrates • Germ and bran are removed leaving the starchy endosperm. • Lower in fiber, vitamins, minerals and other beneficial compounds.

19. Recommended carbohydrate intake • 40 – 45% of total daily calories • 225 – 325 grams of carbohydrates for a 2000 calories diet. • Athletes in training should have a 60 – 70% of total daily calories.

20. FIBER • Non-digestible carbohydrates • Found mainly in plants • Provide bulk for feces in the large intestine, which in turn facilitate elimination.

21. Types of fiber • Dietary fiber: non-digestible carbohydrates and lignin found in grains, legumes and vegetables • Functional fiber: non-digestible carbohydrates isolated from natural sources or synthesized in a lab and added to food • Total fiber: sum of dietary and functional fiber. • Soluble: slows the body’s absorption of glucose and binds cholesterol – containing compounds • Insoluble: binds water making the feces bulkier and softer so they pass easily through the intestines.

22. Vitamins • Organic substances • Required in small amounts to regulate processes within living cells • Humans need 13 vitamins • 4 Fat soluble (A, D, E, K) • 9 Water soluble (C and 8 B – complex vitamins)

23. Functions of vitamins • Help chemical reactions to take place • Help unleash energy stored in carbohydrates, proteins and fats. • Production of red blood cells • Maintenance of nervous, skeletal and immune systems • Antioxidants: preserve healthy cells.

24. Sources of vitamins • Fruits • Vegetables • Grains • Processed food • Flour • Breakfast cereals • Skin exposed to sunlight (D) • Intestinal bacteria (K)

25. Vitamins and disease • DEFICIENCIES • Vitamin A  blindness • Vitamin B 6  seizures • Folate  babies with neural tube defect • Vitamins B 6, B- 12 and folate  heart disease risk • EXTRA VITAMINS • Vitamin A  increase the risk of birth defects • Vitamin B-6  irreversible nerve damage

26. Minerals • Inorganic elements • 17 essential minerals • Needed in small amounts to regulate body functions • Aid in the growth and maintenance of body tissues • Help release energy

27. Sources of minerals • Lean meats  iron • Dairy products  calcium • Whole grains and leafy vegetables  magnesium • Spinach, bananas, mushrooms, white and sweet potatoes  potassium

28. Water • The human body contains 50 – 60% of water • Medium in which most chemical reactions take place • Transports substances around the body • Lubricant • Helps to regulate body temperature

29. Recommended intake of water • Men  3,7 liters of water 3,0 coming from beverages • Woman  2,7 liters of water 2,3 coming from beverages

30. Other substances in food • Antioxidants • Protects the body from the action of free radicals and repair the damage they cause • Phytochemicals • Prevent chronic diseases. • Lower chlesterol levels • Boost the activity of cancer – fighting immune cells • Reduce the effects of carcinogenic compounds.

31. Suplements • Suplements might lack potentially beneficial phytochemicals that are found only in whole foods. • Some vitamins and minerals are dangerous when ingested in excess • Might affect the absorption of other vitamins or minerals • Recommended for: • Pregnant woman • People over age 50 • Smokers • Woman with heavy menstrual flows • Vegetarians (depending on their food choices)) • People with certain diseases or that take certain medications. • Your nutritional needs can be obtained primarily from food.

32. NUTRITIONAL GUIDELINES: • DRIs: dietary reference intakes • Recommended intake levels for vitamins, minerals, and macronutrients • RDAs : recommended dietary allowances • Focused on preventing nutritional deficiency diseases • AI: Adequate Intake • Set when there is to enough information available to set an RDA value. • UL: Tolerable upper intake level • Sets maximum daily intake by a healthy person that is unlikely to cause health problems.

33. NUTRITIONAL GUIDELINES • Daily values • Used as a basis for food labels • Based on several sets of guidelines • Includes standards for fat, cholesterol, carbohydrates, dietary fiber and selected vitamins and minerals. • Represent the appropriate intake levels for a 2000 calorie diet.

34. NUTRITIONAL GUIDELINES • Dietary guidelines for Americans • Issued by the US Department of Agriculture and the Department of Health and Human Services. • Provides general guidance for choosing a healthy diet. • Its guidelines include: • Nutritional recommendations • Weight management recommendations • Physical activity recommendations • Encourages certain food groups: fruits, vegetables, whole grains, an low fat or fat free milk products. • Recommends to reduce the use of certain substances such as sodium and alcoholic beverages.

35. NUTRITIONAL GUIDELINES • USDA’s My Pyramid • Overall food guidance system • Developed to remind consumers to make healthy food choices and to be active everyday 1992 2005

36. USDA’s MY PYRAMID • Color bands represent that all food groups are needed each day for health. • Food groups are color coded: • Grain group • Vegetable group • Fruit group • Milk group • Meat and bean group • Oils are not considered as a food group • Differing widths of the color bands suggest about how much food should be eaten from each group. • Food group bands narrow from bottom to top suggesting to eat nutrient-dense forms of foods. • Steps and person on them symbolize that physical activity should be a part of everyday healthy living. • The slogan “Steps to a Healthier You” suggests that improvement should happen in stages, over time. Pg 80

37. Meeting varied needs • My Pyramid and the Dietary Guidelines for Americans provide a basis that everyone can use to create a healthy diet. However, some population groups face special dietary challenges: • Special population groups—woman, men, college students, older adults, athletes and people with special health concerns. • Food preferences—Vegetarian, lactose-intolerant, ethnic • Situations—Eating out, carrying in, cooking at home

38. Nutritional planning: making informed choices about food

39. Reading food labels

40. Food additives • Uses: • Maintain or improve nutritional quality • Maintain freshness • Help in process or preparation • Alter taste or appearance • Most used: • Salt • Sugar • Corn syrup • Citric acid • Baking soda • Vegetable colors • Mustard • Pepper • Additives of potential concern: • Sulfites  keep vegetables from turning brown, cause severe reactions in some people • Monosodium glutamate  flavor enhancer, some people experiences episodes of sweating and increased blood pressure.

41. Food borne illness • Caused by pathogens found in food • Raw or undercooked animal products such as chicken, hamburger, oysters, eggs. • Drinking water, fruits • Symptoms include acute gastroenteritis, diarrhea, vomiting, fever and weakness.

42. Irradiated food • Food can be treated with gamma rays, X-rays or high-voltage electrons to kill potentially harmful pathogens. • Irradiation kills most pathogens, but it does not completely sterilize foods

43. Environmental contaminants and organic foods • Certified organic goods meet strict production, processing, handling and labeling criteria. • For plant products • Must limit pesticide residues • No sewage sludge • For animal products: • Feed with organic products • Access to outdoors • No use of antibiotics or hormones • No genetic engineering, ionizing, radiation. • Organic products might not be chemical free

44. Products with higher pesticide residues Products with little pesticide residue • Apples, • Peppers • Celery • Cherries • Imported grapes • Necttarines • Peaches • Pears • Potatoes • Red raspberries • Spinach • Strawberries • Asparagus • Avocados • Bananas • Brocoli • Cauliflower • Corn • Kiwi • Mangoes • Onions • Papaya • Pineapples • Peas

45. Remember… • No single type of diet provides optimal health for everyone • Many cultural dietary patterns can meet people’s nutritional requirements • Customize your food plan based on your age, gender, weight, activity level, medical risk factors and personal tastes

46. Lab 3.3 Informed food choices • Choose three food items to evaluate. • You might want to select three similar items, such as regular, low-fat and non fat salad dressing or three very different items. • Record the information from their food labels in the table.

47. Lab 3.1. • List your daily menu • During a regular week day • During a weekend. • Use apendix B to guide you • Or MyPyramid.gov MyPyramid Tracker • Use figure 3,7 to compare your results to the recommendations of MyPyramid for a 2000 calories diet • Compare your results and evaluate what changes should you make to improve your diet.