Chapter 3 – How Nutrients Become You

1. Chapter 3 – How Nutrients Become You The Basics of Nutrition

2. The Basic Truth of Nutrition • “You are what you eat” • Food is your body’s fuel • Food is eaten • It is broken down into simpler elements • Energy is released and nutrients are used to help build, repair, and maintain body cells • By-products are discarded as waste

3. There Are 6 Nutrient Groups • These substances are best obtained from the food you eat • The body needs elements from all 6 groups in order to function properly and maintain good health • Carbohydrates • Fats • Proteins • Vitamins • Minerals • Water

4. Variety Is Key • Where do they fit? • Nectarine • Wheat bread • Trail mix • Water • Why wouldn’t an unlimited supply of only one of these foods sustain life?

5. The Chemistry of Nutrition () • I know, I know – who wants to learn chemistry in HCR??? • To understand the basics of nutrition, there has to be some understanding of basic chemistry – SORRY!  • No worries – we won’t get too crazy with it

6. The Chemistry of Nutrition • Your body and the foods you eat are composed of chemical elements • Elements are the simplest substances from which all matter is formed • An atom is the smallest part of an element • A molecule is the smallest amount of a substance that has all the characteristics of the substance • Molecules are 2 or more atoms bonded together

7. The Chemistry of Nutrition • The atoms in a molecule may be all the same element, or they may be different elements • When atoms of different elements bond together, they form compounds

8. The Chemistry of Nutrition • 5 of the basic nutrient groups are compounds (combination of different elements) • Carbohydrates • Fats • Proteins • Vitamins • Water • 1 basic nutrient group is elements (simplest substance) • Minerals

9. Functions of Nutrients • The essential nutrients from food are used to • Build and repair body tissues • Regulate all body processes • Provide energy • When provided with the proper nutrients, your body can perform all of these functions in harmony, which optimizes health, wellness, and performance

10. Building and Repairing Body Tissues • The body is made up of billions of cells • Cells divide, producing 2 new cells each time, which accounts for your growth • New cells also repair damaged body tissues and replace old cells • All cells are formed with materials that come from food • Therefore, your body needs proper amounts of nutrients to help make new cells

11. Building and Repairing Body Tissues • Periods of rapid growth require greater amounts of nutrients • Pregnancy • Infancy • Adolescence • Illness/injury recovery • Lacking proper nutrients during these periods can negatively affect growth potential, strength, health, healing, learning abilities, and behavior patterns

12. How Does Hunger Affect Your: • Mood? • Attitude? • Thinking? • Physical performance?

13. Regulate Body Processes • The proper amounts and types of nutrients keep body processes running smoothly • Examples of body processes that rely on nutritional components • Circulation of body fluids • Maintaining the correct acid-base level in the blood • Digestion • Absorption • Metabolism

14. Provide Energy • Food is a source of energy for performance • The quality of the food you eat affects how your body will run • The more active you are, the more energy you will need to fuel your body processes

15. Provide Energy • Chemical reactions that take place in your cells release energy from nutrients that you get from food • Carbohydrates and fats are the main nutrients used for energy • Proteins can be used, but the body prefers to save them for other vital functions • Vitamins, minerals, and water do not provide energy, but the body needs them to help regulate the release of energy from carbs, fats, and proteins

16. The Energy Value of Food • Measured in units called kilocalories (kcal) • Commonly known as calories • Only certain nutrients provide energy • 1 gram of carbohydrate = 4 kcal of energy • 1 gram of fat = 9 kcal of energy • 1 gram of protein = 4 kcal of energy • Water, vitamins, and minerals do not yield energy, and therefore do not have a calorie content

17. Alcohol • Alcohol does have a calorie content • 1 gram of alcohol = 7 kcal of energy • It is not considered a nutrient because: • It does not promote growth (it inhibits) • It does not maintain cells (it destroys) • It does not repair tissues (it inhibits healing) • Determining Energy Values

18. Digestion • The process by which your body breaks down food, and the nutrients in food, into simpler substances • The blood can carry these simpler substances to the cells for use in growth, repair, and maintenance • Digestion occurs throughout the digestive system through mechanical and chemical means • Mechanical digestion – occurs when food is crushed and churned • Chemical digestion – occurs when food is mixed with acids and enzymes • Enzyme – a type of protein produced by cells that cause specific chemical reactions • In digestion, they cause food particles to break apart into simpler substances

19. Gastrointestinal Tract (GI Tract) • The muscular tube through which food passes from the mouth to the anus • Roughly 25-30 feet in length • Each section has different functions • Mouth → esophagus → stomach → small intestine → large intestine • Pg. 49

20. Mouth • Mastication (chewing) is the1st step in digestion • Important mechanical digestive process as chewed food is broken down more easily by the body • Food is mixed with saliva in the mouth, which helps to moisten, soften, and dissolve food • Included in saliva is salivary amylase, an enzyme which helps to break down starches

21. Esophagus • Passageway from mouth to stomach • About 10 inches long • Food moves along this passageway through a series of muscular squeezing actions called peristalsis • Involuntary muscle action that is part of mechanical digestion

22. Stomach • The stomach produces gastric juices to aid in digestion • Made up of acids, enzymes, and mucus • Acids and enzymes break down food, and mucus softens and lubricates chyme • The gastric juices mix with the chewed food to form chyme • The stomach can typically hold about a quart of food • Food generally stays in the stomach for 2-3 hours, depending on the type of food • Liquids leave first • Fats leave last

23. Small Intestine • About 95% of digestion takes place here • Has 3 sections, and is roughly 20 feet in length and 1 inch in diameter • Takes food about 5-14 hours to move through the small intestine through peristalsis action • The small intestine is aided by other organs during digestion • Pancreas – adds digestive enzymes • Liver – adds bile for breaking down fats • *Nutrient Digestion in the Small Intestine

24. Large Intestine • Also known as the colon • Main job is to reabsorb water • Very little digestion occurs here • About 5-6 feet long • Chyme stays in the colon for 1-3 days before elimination • Solid wastes that result from digestion are eliminated as feces • *Food Breakdown

25. Absorption of Nutrients • Absorption is the passage of nutrients from the digestive tract into the circulatory or the lymphatic system • Circulatory system – amino acids, monosaccharides, minerals, and most vitamins • Lymphatic system – nutrients from fats • Most nutrients pass through the walls of the small intestine • The small intestine is lined with tiny, finger-like projections called villi • Villi increase the surface area of the small intestine and aid in absorption of nutrients

26. Intestinal Villi

27. Metabolism • Once digestion and absorption have taken place, the circulatory system carries the nutrients to individual cells • Metabolism is all the chemical changes that occur as cells produce energy and materials needed to sustain life • Cells break down nutrients to release energy, which is stored in the muscles as ATP • The waste products created through cell metabolism are eliminated through the kidneys, lungs, and skin

28. Factors That Affect Digestion and Absorption • Eating Habits Affect Digestion • Don’t eat too much or too little • Eat a variety of foods in order to get all of the required nutrients • Include high-fiber foods to provide bulk and aid in removing toxins • Foods high in fat will take longer to digest as fats are the last nutrient component to leave the stomach

29. Factors That Affect Digestion and Absorption • Emotions • Fear, anger, and tension can lead to digestive difficulties • Reducing stress and tension during mealtimes will allow for better absorption of nutrients

30. Factors That Affect Digestion and Absorption • Food Allergies • A food allergy is a reaction of the immune system to certain proteins found in food • The immune system protects the body from invaders by forming antibodies • When you are allergic to a food, your body releases antibodies in response to that food, leading to allergy symptoms • These symptoms can include, but are not limited to, vomiting, intestinal distress, rashes, and swelling • This is different from a food sensitivity, such as lactose intolerance

31. Factors That Affect Digestion and Absorption • Physical Activity • Aids digestion and metabolism • Stimulates a healthy appetite and strengthens the muscles of the internal organs • Helps move food through the GI tract • Reduces stress

32. Digestive Disorders • A nutritious diet can help to avoid or manage most digestive disorders • Some disorders require medical treatment in order to make certain that all required nutrients make it to the cells in order to maintain life

33. Digestive Disorders • Diarrhea • Frequent expulsion of watery feces • Causes food to move through the digestive system too quickly for nutrients to be absorbed • Also leads to loss of body fluids as the food moves too quickly through the large intestine for the water to be reabsorbed

34. Digestive Disorders • Constipation • Occurs when chyme moves too slowly through the large intestine, leading to the reabsorption of too much water • Causes the feces to become too hard and dry, which can lead to painful elimination and hemorrhoids • Often caused by erratic eating habits, low fiber intake, lack of physical activity, and inadequate fluid intake

35. Digestive Disorders • Indigestion • Difficulty in digesting food • Can be caused by stress, eating too much or eating too fast, or eating particular foods • Can include gas, stomach cramps, and nausea

36. Digestive Disorders • Heartburn • A burning pain in the middle of the chest caused by stomach acid flowing back into the esophagus • Can be reduced by avoiding acidic foods, stress, lying down right after eating, and taking antacids

37. Digestive Disorders • Ulcer • An open sore in the lining of the stomach or small intestine caused by bacterium • Risk is increased by stress, heredity, alcohol use, and aspirin abuse • Usually treated with antibiotics, as well as decreasing stress, alcohol, caffeine, and tobacco use

38. Digestive Disorders • Gallstones • Small crystals that form from bile in the gallbladder • These stones block the release of bile into the small intestine, causing pain and slowing the digestion of fats • Treatment includes a diet low in fats, and often requires surgery to remove the gallbladder

39. Digestive Disorders • Diverticulosis • The formation of abnormal pouches in the intestinal wall • Can occur when the intestinal muscles become weak, such as when a diet is low in fiber • These pouches can become inflamed, leading to a painful condition called diverticulitis • *What Could Be Wrong • *Digestive Disorders