Understanding Nutrition: Components of a Balanced Diet

1. Sheet #10 Lecture (Nutrition) Lecture Date :- 30-7-2018 Done By :- BatoolQutami Edited By :- بان عدمات Doctor :- Nabil Amer

2. If you come by any mistake (whether it be spelling, grammatical or scientific) while browsing this sheet, kindly report it to the academic team 2023od@gmail.com

3. Nutrition

4. Learning objectives What we will learn in this lecture: • The components of a balanced diet • How the body gets energy: carbohydrates, fats and proteins • How energy needs vary depending on the individual • The importance of balancing energy intake with energy needs • The importance of vitamins, minerals and fibre • The importance of drinking enough water. Learning objectives

5. Why Do We Eat?

6. Sheet Page 1 • Why do we eat? • Food is an energy source. • To regulate metabolism in our body. • For growth and development. • Appearance. • Mood and behavior. • Vegetarians arepeaceful in comparison to people who eat high protein contents because proteins need more hormones and blood supply for digestion so they are more aggressive.

7. General Nutrition Concepts • Influences of Nutrition • Health • Appearance • Behavior • Mood • Role of Nutrients in Diet • Growth and development • Provide energy • Regulate metabolism

8. Classes of Nutrients • Carbohydrates • Proteins • Fats • Vitamins • Minerals • Water

9. Diet and nutrition A good diet on its own will not make you more skilful or fit as a performer, but it will help you make the most of your abilities. Participation in sport or exercise requires energy. This energy is obtained from the food that we eat. In order to optimize our performance, it is important that we have an appropriate and balanced diet. The amount and type of food that we eat on a daily basis is very important to both health and performance. A good diet helps our bodies to stay healthy and gives us the energy that we need to exercise.

10. What is a Balanced Diet?

11. A balanced diet Everyone, whether involved in sport or not, should try to eat a healthy, balanced diet. A balanced diet includes all the things that your body needs. To achieve this, you need to eat a range of different types of food in the right proportions. If you eat a balanced diet, you will get the energy and nutrients required to participate in exercise and to recover from it quickly. This pie chart shows the various different food groups in their recommended proportions.

12. A balanced diet When considering where to get the energy needed for sport, it is more helpful to think about food in terms of what molecules it contains, rather than where it comes from. Energy in food comes in three main forms: Carbohydrates Proteins Fats The body also requires vitamins, minerals, fibre and, of course, water in order to function properly.

13. Carbohydrates Carbohydrates are the body’s main source of energy. They come in two kinds: Simple carbohydrates (sugars)These can provide a lot of energy for immediate use, but contain no other useful nutrients. Complex carbohydrates (starches)These are good sources of energy. The body can easily store energy from carbohydrates for rapid use by the muscles, so they are particularly important for athletes. Starchy foods often also contain lots of useful vitamins, minerals and fibre.

14. Sheet Page 2 • Examples of simple carbohydrates :all types of sugars present in fruits, honey, etc. • Examples of complex carbohydrates :rice, bread and pasta. • Individuals prefer complex carbohydrates for daily energy needs.

15. respiration glucose oxygen Carbohydrates Complex carbohydrates should provide around half of your daily energy needs. If you are performing strenuous exercise, this should increase to 60–70%. Energy from carbohydrates is converted to a glycogen. This is stored in the liver and the muscles. When energy is needed, the body changes the glycogen to glucose which is used by the muscles during respiration. energy If you eat too much carbohydrate, however, the body will store it as fat.

16. Sheet Page 3 • Excess carbohydrates are converted to fats because the ability of muscles and liver to store glycogen is limited. However, fats cannot be converted to carbohydrates. • To lose weight you have first to reduce the amount of carbohydrates you eat.

17. C 100 A 35% R 50% 80 SIMPLE 55% P B E O R H 60 65% C Y E D 50% 40 COMPLEX 45% N R A 20 T E S 0 1910 1950 1980 Trends in Carbohydrate Consumption Over time, the consumption of simple carbohydrates has increased.

18. Carbohydrate loading Marathon runners and other endurance athletes often use a technique called carbohydrate loading (glycogen loading). 7 days before event – energy stores are completely depleted as training intensity peaks. 6–4 days before event – athletes stick to a low-carbohydrate, high protein diet, keeping glycogen stores low. Night before event – athletes often have a large carbohydrate-rich meal, sometimes referred to as a pasta party. 3–1 days before event – athletes swap to a carbohydrate-rich diet to build up glycogen stores again. This process is designed to trick the body into storing extra glycogen in the liver and muscles.

19. SHEET Page 4 • Some athletes at the day before the event take a blood unit from another person so that they have more oxygen concentration and this will give them more energy. • Other athletes spend many days in high altitude areas to produce more RBCs.

20. Fats Fats are also used for energy, but only when stores of carbohydrate run low. Weight-for-weight, fat contains more than twice as much energy as carbohydrates or proteins. However, lots of oxygen is required to release this energy. This means that energy can only be released slowly from fats. Fats supply the energy we need for endurance activities.

21. SHEET Page 5 • Fats are the highest source of energy. • Fats: 9 kilocalories per gram. • Carbohydrates: 4 kcal per gram, • Protein: 4 kcal per gram, • When fat is converted to energy it gives us ketone bodies, which are acids, then brain and muscles will use these acids. • When body uses fat, it produces ketone bodies (acetoacetate, beta-hydroxybutyrate, and acetone) which will cause a condition called“ketosis”, this happens especially in diabetes : because of the extra useless glucose in circulating blood, the body will use fats instead of carbohydrates and a diabetic coma will occur because ketone bodies are acids.

22. SHEET Page 6 • EXTRA INFO THE DOCTOR DID NOT MENTION: • Ketone bodies are three water-soluble molecules (acetoacetate, beta-hydroxybutyrate, and their spontaneous breakdown product, acetone) containing the ketone group that are produced by the liver from fatty acids during periods of low food intake (fasting), carbohydrate restrictive diets, starvation, prolonged intense exercise.

23. The two types of fat There are two types of fats: Saturated fats – these are usually found in foods such as milk, butter, cheese and meat. Unsaturated fats – these are usually found in foods such as fish oils, cooking oils and sunflower seed oil. Saturated fats can be converted into cholesterol by the liver. High blood cholesterol is linked to heart disease. For this reason, no more than 10% of your energy should come from eating saturated fat.

24. Composition of Oils (%) Type Sat Poly Mono safflower 9 75 16 sunflower 10 66 24 corn 13 59 28 soybean 14 58 28 sesame 14 42 44 peanut 17 32 51 palm 49 9 42 olive 14 8 78 canola 7 35 58

25. SHEET Page 7 • Olive oil has the highest mono unsaturated fatty acids then Canola oil, which is genetically modified. • {you have to know the highest and the lowest ones with mono-unsaturated fats}

26. Hydrogenation Process Margarine هي زبدة نباتية ناتج عن تحويل الزيت النباتي تحت درجة حرارة عالية وعامل مساعد

27. Recommendations for Fat Consumption • Dietary Fat Recommendations • Less than 30% of calories in diet from fat • Less than 1/3 of dietary fat should be saturated • Ways to Decrease Intake of Fat • Minimize "fast" foods • Minimize processed foods • Use better cuts of meats • Use low fat alternatives • Decrease use of condiments (salts…) • Eat lower fat snacks

28. Fats Because fat contains so much energy, you can easily eat more than your body needs. Excess fat is stored as body fat, causing weight gain. In some sports like sumo wrestling and shot-putting, extra bulk can be an advantage. However, for most performers, extra body fat will hamper their performance. If your body weighs more, it is more difficult to move. Sportspeople who need to move fast, like runners and games players, should limit the amount of fat in their diet.

29. Proteins Proteins are used to generate energy only when the body has exhausted its stores of carbohydrates and fats. Proteins are very important in the body for other reasons. Our muscles and other tissues are made from proteins. The body manufactures proteins from amino acids. Your body cannot make all of the different types of amino acid that it needs – you have to consume some of them in the food that you eat. The protein you eat is broken down into amino acids and used by the body to build cells, make blood and repair and replace tissue. Proteins are made from sequences of amino acids.

30. Types of Protein • Sources of Protein • Animal (complete) • meats, dairy • Vegetable (incomplete) • beans, nuts, legumes, grains • Types of Amino Acids • Nonessential (12 ) – can be made by body • Essential (8) – must be taken by food Amino acids linked together

31. SHEET Page 8 • Also Proteins are important for hormones and receptors • Complete protein(high biological value) is a protein that contains all of the essential amino acids such as milk ,meet, eggs. • Incomplete protein(low biological value) doesn’t contain all the essential amino acids like proteins in the membranes and in vegetables • Animal’s proteins are proteins with high biological value, while plant’s proteins are proteins with low biological values.

32. Protein Requirements • RDA average = 0.8 g/kg/day • RDA athlete = 1.2-1.6 g/kg/day High levels of protein intake above 2 g/kg/day can be harmful to the body

33. Sheet Page 9 • RDA= Recommended dietary allowance • An individual who weighs 80 kg ,needs 8 g/kg/day of proteins

34. Proteins Proteins are especially important for sportspeople who need to build up large, powerful muscles. Performers in sports like weightlifting, rugby and sprinting can benefit from a protein-rich diet. Proteins are also needed by performers who are recovering from injury in order to repair damaged tissue.

35. Your energy needs The body uses energy all the time just to keep warm, keep the heart beating and the lungs breathing. The Basal Metabolic Rate (BMR) is the amount of energy we require just to stay alive, awake and warm. To move around, digest food and exercise, we need even more energy. This is called our working energy. Our working energy depends on how active we are. basal metabolic rate + working energy Total energy needed = This can be measured in either kilojoules (kj) or kilocalories (kcal).

36. What Is Protein-Calorie Malnutrition? Causes Lack of calorie and protein intake is the primary cause of PCM, but many secondary causes can also cause the disorder. Cancer, alcoholism, cardiac diseases, AIDS infection and kidney disease can all cause cachexia, loss of appetite and muscle wasting. Disorders that cause the body to use up a higher number of calories than usual, such as severe burns or other trauma, can also cause PCM. Gastrointestinal diseases that affect absorption may lead to PCM as well.

37. Types The two disorders most commonly associated with PCM in children are marasmus, sometimes called the “dry” form of the disorder, and kwashiorkor, known as the “wet” form.

38. Sheet Page 10 • The left picture :MARASMUS >>complete absence of proteins and carbohydrates. • The right one: KWASHIORKOR>>he has carbohydrates but doesn’t have proteins.

39. Symptoms of PCM • muscle wasting, • lack of subcutaneous fat, • slow heart beat, • difficulty maintaining body temperature, • poor wound healing and • low energy levels. • Hair becomes dry, brittle and sparse, while skin turns dry, cool to the touch and rough. • Diarrhea commonly occurs. In patients with kwashiorkor, fluid accumulates in the abdomen and other tissues. • Blood pressure and respiratory rate may also slow, and • the person becomes susceptible to infection as the immune system fails. • If the disease progresses, organs such as the heart, liver and kidneys fail. Death will occur if the disease continues to progress without intervention.

40. Individual energy needs The amount of energy required varies from person to person. It depends on a number of factors: Age – as you grow up and your body gets larger, it requires more energy. However, after the age of about 40, your metabolism slows down and you don’t need to eat as much. Size – larger people require more energy to keep their bodies functioning and to move them around. Sex – males usually require more energy than females because they tend to be more heavily built. Lifestyle – the more activity you do, the more energy you will require.

41. Individual energy needs per day (kcal) Why do you think that, on average, adult males working in offices need fewer calories than 16 year-old males? Answer: 16 year-old males are relatively active compared to office workers – they have a higher working energy.

42. Energy balance When you participate in sport and other activities, you burn extra energy. The amount of energy you use will depend on: • what type of exercise you do • how long you exercise for • how hard you exercise. Here are some guidelines for the energy used in different activities:

43. PRO PRO (10-15%) CHO FAT (30%) FAT CHO (55-60%) Recommended Dietary Intake

44. Vitamins Your body needs vitamins to help it work normally. Vitamins are needed for many functions including: • releasing energy from food • repair and growth of tissues • resisting infection and disease • regulating chemical reactions in the body. Fruit and vegetables contain a lot of vitamins.

45. Vitamin Guidelines • A balanced diet containing recommended servings of carbohydrates, fats and proteins will meet the RDA standards • Extra servings of green and yellow vegetables may be beneficial • Extra consumption of citrus and other fruits may be beneficial

46. Vitamin Supplementation? • Not necessary if diet is healthy • Multivitamins are safe (100% RDA) • Not all vitamins are “pure” • Can be toxic at high doses

47. Minerals Minerals are basic elements that are found in the air and the earth. The body needs small amounts of certain minerals in order to stay healthy. Vegetables, dairy products and dried fish Keeping bones and teeth hard Red meat, liver, beans, lentils and green vegetables Making blood, preventing tiredness and anaemia Seafood and dairy products Maintaining the thyroid gland

48. Minerals • Inorganic elements found in food that are essential to life processes • About 25 are essential • Classified as major or trace minerals • RDA’s have only been determined for 7 minerals

49. Mineral Guidelines • A diet containing recommended servings of carbohydrates, fats and proteins will meet the RDA standards • Extra servings of green and yellow vegetables may be beneficial • Dietary supplementation of Calcium is beneficial for post-menopausal women • Salt should be limited in the diet

50. Populations Who May Benefit from Supplementation • Pregnant/lactating women • Alcoholics • Elderly • Women with severe menstrual losses • Individuals on VLCD’s ( very low caloric diet) • Strict vegetarians • Individuals taking medications or with diseases which inhibit nutrient absorption