Chapter 5 Nutrition and Your Health Lesson 1

Chapter 5 Nutrition and Your Health

Lesson 1 Nutrition During the Teen Years

The Importance of Good Nutrition • Nutrition – The process by which the body takes in and uses food • Calories – Units of heat that measure the energy used by the body and the energy that foods supply to the body • Nutrients – Substances in food that your body needs to grow, to repair itself, and to supply you with energy

What Influences Your Food Choices? • Hunger and Appetite – Hunger: unlearned, inborn response, is a natural physical drive that protects you from starvation – Stomach walls contract => stimulates nerve endings=> sends signal to brain=>eat and stomach walls are stretched=>nerve endings are no longer stimulated • Food and Emotions – Do you eat more or less when you are stressed, frustrated or depressed? – Snack if you are bored? Do you reward yourself with food? – Using food to relieve tension or boredom or to reward oneself can result in overeating and unhealthy weight gain

What Influences Your Food Choices? • Food and Your Environment – Family, friends and peers: • many eating habits are shaped as people grow up, influenced to try new things – Cultural and ethnic background – Convenience and cost: • Busy families may rely on microwaveable foods – Advertising: • Spend millions of dollars to influence people to eat certain foods

Lesson 2 Nutrients

Carbohydrates • Carbohydrates: are the starches and sugars present in foods – Made up of carbon, oxygen and hydrogen – Are the body’s preferred source of energy – Providing 4 calories per gram – Classified as simple or complex – Most nutritionists recommend 55 to 60 percent of your daily calories come from carbohydrates, mainly complex

Carbohydrates cont 1. , • Simple Carbohydrates • Complex Carbohydrates – Sugars, such as fructose and lactose, found in fruit and milk – Sucrose: sugarcane and sugar beets=>refines to make table sugar – Starches, found in whole grains, seeds, nuts, legumes (dried peas and beans) and tubers (root veggies such as potatoes) – The body must break these down into simple carbs before they can be used for energy

Role of Carbohydrates • Body converts all carbohydrates to glucose, a simple sugar that is the body’s main source of energy • Glucose that your body does not use right away is stored in the liver and muscles as a starch-like substance called glycogen • When more energy is needed your body converts the glycogen back to glucose • However, it is possible to take in more carbohydrates than your body can use right away=>the body converts and stores the excess as body fat

Carbohydrates cont 2. , • Fiber – An indigestible complex carbohydrate that is found in the tough, stringy parts of vegetables, fruits and whole grains – Although it cannot be digested and used as energy, fiber helps move waste through the digestive system – Fiber helps reduce the risk of heart disease – Examples of Fiber? ? ?

Proteins • Nutrients that help build and maintain body cells and tissues • Made of long chains of substances called amino acids • Your body can manufacture all but 9 of the 20 different amino acids that make up proteins • The 9 come from the food we eat

Proteins cont 1. , • Complete Proteins – Contain adequate amounts of all nine essential amino acids – Animal products such as fish, meat, poultry, eggs, milk, cheese and yogurt, and many soybean products • Incomplete Proteins – Lack one or more of the essential amino acids – Beans, peas, nuts and whole grains – Consuming a few incomplete proteins together is equivalent to consuming a complete protein (over the course of a day, not in one meal)

Proteins cont 2. , • Role of Proteins – During major growth periods, such as infancy, childhood, adolescence and pregnancy, the body builds new cells and tissue from amino acids in proteins – Provides the body with energy (not the main source) – Replaces damaged or worn-out cells by making new ones from proteins – The body also uses proteins to make enzymes, hormones and antibodies • Enzymes-substances that control the rate of chemical reactions in your cells • Hormones-regulate the activities of different cells • Antibodies-help identify and destroy disease-causing organisms

Fats • Some fats in diets are good for health • Lipid: a fatty substance that does not dissolve in water • Fats provide more than twice the energy of carbohydrates or proteins • The building blocks of fats are fatty acids, molecules made mostly of long chains of carbon atoms, with pairs of hydrogen atoms and single oxygen atoms attached • Essential fatty acids: fatty acids that the body needs, but cannot produce • Fatty acids are classified as either saturated or unsaturated – most are a mixture of the two

Fats cont. , • Saturated Fatty Acids – Holds all the hydrogen atoms – Fats high in saturated fatty acids are usually solid at room temperature – Animal fats and tropical oils have a a high proportion of saturated fatty acids – Fats in beef, pork, egg yolks and dairy foods are higher in saturated fatty acids than are the fats in chicken and fish – Associated with an increased risk of heart disease • Unsaturated Fatty Acids – Has at least one unsaturated bond, a place where hydrogen can be added to the molecule – Usually liquids (oils) at room temperature – Vegetable fats – olive oil, canola, soybean, corn and cottonseed oils – contain a high proportion of unsaturated fatty acids – Associated with a reduced risk of heart disease – Two types: 1. Monounsaturated fatty acids and 2. Polyunsaturated fatty acids

The Role of Fats • Provide a concentrated form of energy • Transport vitamins A, D, E and K in your blood and serve as sources of linoleic acid, an essential fatty acid that is needed for growth and healthy skin • Adds flavor and texture to food • Take longer to digest than carbohydrates and proteins, so they help satisfy hunger longer • Fats usually contain more calories than other foods so consuming an excess amount can lead to unhealthy weight gain and obesity • No more than 20 to 30 percent of your totally daily caloric intake

The Role of Cholesterol • Waxy lipid like substance that circulates in blood • Your body uses the small amount it manufactures to make cell membranes and nerve tissue and to produce many hormones, vitamin D and bile, which helps digest fats • Excess blood cholesterol is deposited in arteries, including the arteries of the heart. This increases the risk of heart disease • High cholesterol may be hereditary • Tend to rise with age • Reduce your risk by eating a diet low in saturated fats and cholesterol • Dietary cholesterol is found only in animal products such as egg yolks, meats (organ meats) and high-fat milk products • Losing excess weight can also lower cholesterol levels

Vitamins • Compounds that help regulate many vital body processes, including digestion, absorption, and metabolism of other nutrients • Classified as either water or fat soluble – Water-soluble vitamins dissolve in water and pass easily into the blood during digestion • the body does not store these so you must replenish them regularly – Fat-soluble vitamins are absorbed, stored and transported in fat • Your body stores these in your fatty tissue, liver and kidneys • Excess build-up of these can be toxic

Minerals • Substances that the body cannot manufacture but that are needed forming healthy bones and teeth and for regulating many vital body processes

Water • Vital to every body function • Transports other nutrients to and carries wastes from your cells • Lubricates joints and mucous membranes • Swallow and digest foods, absorb other nutrients and eliminates wastes • Through perspiration, water helps maintain normal body temperature • Important to drink at least 8 cups of water each day – Plain water, milk and juice are the best sources – Caffeine drinks are not good choices – causes increased urination – Foods, such as fruits and vegetables contain some water

Lesson 3 Guidelines for Healthful Eating

Dietary Guidelines for Americans • Set of recommendations for healthful eating and active living • Grouped into three broad areas known as the ABCs of good health • The U. S. Department of Agriculture (USDA) and the Department of Health and Human Services (DHHS)

ABCs • A: Aim for Fitness – Fitness goals: aim for a healthy weight and be physically active each day • B: Build a Healthy Base – Healthful eating plan: Food Guide Pyramid – a guide for making healthful daily food choices – Make your food choices carefully, choose a variety of grain products, especially whole grains, choose a variety of fruits and vegetables daily and keep food safe to eat – Understanding serving sizes: portion control

ABCs cont. , • C: Choose Sensibly – Choosing a diet that is low in saturated fat and cholesterol and moderate in total fat • No more than 30% of calories should come from fats – Choosing beverages and foods to moderate your intake of sugars • Identify added sugars and limit your intake – Choosing and preparing foods with less salt • Sodium is an essential mineral, helps transport nutrients into your cells and helps move wastes out • Moderate your salt intake (pg. 126) • Watch out for processed foods • Taste your food before you salt it • Season foods with herbs and spices instead of salt

Healthy Eating Patterns Variety, Moderation and Balance • The Importance of Eating Breakfast – Fresh supply of energy, improves mental and physical performances and reduces fatigue later in the day, help maintain a healthy body weight • Nutritious Snacks – Whole grain products, fruits and vegetables • Figure 5. 6 • Eating Out, Eating Right – For less fat order foods that are grilled, baked or broiled – Ask for sauces on the side or to hold the sauce – Always remember portion control

Lesson 4 Food and Healthy Living

Nutrition Labeling • The law requires that Nutrition Facts panels be placed on packages of food that are intended for sale • Most food labels also list the food’s ingredients by weight, in descending order, with the ingredient in the greatest amount listed first • Food Additives: substances intentionally added to food to produce a desired effect (flavor, color or lengthen its storage life) • Sugar and Fat Substitutes: aspartame - which is essentially calorie-free (diet sodas), olestra - passes through the body undigested (potato chips)

Product Labeling • Nutrient Content Claims – – – Light or Lite Less Free More High, Rich In, or Excellent Source Of – Lean • Open Dating – – Expiration date Freshness date Pack date Sell-by date (or pull date)

Food Sensitivities • Food Allergy – A condition in which the body’s immune system reacts to substances in some foods • These substances are called allergens, are proteins that the body responds to as if they were pathogens, or foreign invaders • Simple blood test to find an allergy to a food • Reactions can be a rash to vomiting to sneezing • Food Intolerances – A negative reaction to a food or part of food caused by a metabolic problem, such as the inability to digest parts of the certain foods or food components – Hereditary such as lactose intolerant

Foodborne Illness • Food poisoning • May result from eating food contaminated with pathogens (disease-causing organisms), the poisons they produce, or poisonous chemicals • Many times it cannot be seen, smelled or tasted • Protect yourself by becoming knowledgeable about the causes of such illnesses and ways to keep food safe

Causes and Symptoms of Foodborne Illness • According to the Centers for Disease Control and Prevention (CDC), bacteria and viruses cause most common foodborne illnesses • Bacteria that contaminate food include Campylobacter, Salmonella, and E. coli • Viruses include the Norwalk and Norwalk-like viruses • Food becomes contaminated with these pathogens in two ways: 1. by an infected person and 2. animals raised or caught might harbor these in their tissues – Pasteurization: the process of treating a substance with heat to destroy or slow the growth of pathogens Commons symptoms: nausea, vomiting, diarrhea and fever

Minimizing Risks of Foodborne Illness • Clean – Cross-contamination: the spreading of bacteria or other pathogens from one food to another – Wash everything • Separate – Separate raw meat, fish and poultry from everything else when shopping and at home store separately from other foods • Cook – 160 degrees F for ground beef, 170 degrees F for roasts and poultry and 145 degrees F for fish – When cooked fully the juices should run clearly • Chill – Cold temperature slow the multiplication of bacteria – Refrigerate or freeze perishable foods – Refrigerate or freeze prepared foods within 2 hours after a meal or even sooner on a hot day, discard food that has been sitting out longer