Nutrition and Your Health Chapter 5: Lessons 1 & 2 What is Nutrition? The process by which the body takes in and uses food. Good nutrition enhances your quality of life and helps prevent diseases. Provides you with the calories and nutrients your body needs for maximum energy and wellness. Calories Units of heat that measure the energy used by the body and the energy that foods supply to the body This energy fuels everything you do, from exercising and playing sports to doing your homework and talking with friends. Nutrients Substances in food that your body needs to grow, to repair itself, and to supply you with energy. Making healthy food choices will provide your body with the nutrients it needs to help you look your best and perform your best. Hunger vs. Appetite Hunger is a natural physical drive that protects you from starvation. Appetite is a desire, rather than a need, to eat. Why Do You Eat? Emotional needs stressed, frustrated, depressed, bored Environmental influence family & friends cultural & ethnic background convenience & cost advertising Six Basic Nutrients Carbohydrates Fats Protein Vitamins Minerals Water Carbohydrates Starches and sugars present in foods The body’s primary energy source 60% of diet Simple vs. Complex Simple Carbohydrates Sugars Fructose (fruit) and lactose (milk) Sucrose (occurs naturally in many plants and refined to make table sugar) Sugars are added to many manufactured food products Complex Carbohydrates Starches Found in whole grains, seeds, nuts, legumes (dried peas and beans) The body must break down complex carbohydrates into simple carbohydrates before it can use them for energy Role of Carbohydrates Converted to glucose (sugar) Body’s main source of energy Glucose that is not used right away is stored in the liver and muscles as a starch-like substance called glycogen. When more energy is needed, glycogen is converted back to glucose. Taking in more carbohydrates than your body needs (or can store as glycogen) is then stored as body fat. Fats Secondary energy source BUT, fats provide more than twice the energy of carbohydrates or proteins 30% of diet Lipid – fatty substance that does not dissolve in water Saturated vs. Unsaturated Role of Fats Source of energy Transport vitamins A, D, E, and K in your blood Serve as a source of linoleic acid – essential fatty acid that is needed for growth and healthy skin Add flavor and texture to food Help satisfy hunger, but high in calories Proteins Builds and repairs tissue Secondary energy source 10% of your diet Proteins Made of long chains of substances called amino acids. Your body can’t manufacture 9 of the 20 different amino acids The other 9 are called essential amino acids that you must get from the foods you eat. Complete vs. Incomplete Proteins Complete – Contain adequate amounts of all nine essential amino acids. Animal products (fish, meat, poultry, eggs, milk, cheese and yogurt, soybean products) Incomplete – Lack one or more of the essential amino acids Beans, peas, nuts and whole grains Role of Proteins Body uses proteins to make enzymes (substances that control the rate of chemical reactions in your cells), hormones (regulate the activities of different cells) and antibodies (help identify and destroy disease-causing organisms). Energy supply Vitamins Required for growth and proper body functions A,D,E,K (fat soluble) B,C (water soluble) Vitamins Compounds that help regulate many vital body processes, including digestion, absorption, and metabolism of other nutrients. Water soluble vs. Fat soluble Water Soluble Water-soluble vitamins dissolve in water and pass easily into the blood during digestion. The body doesn’t store these vitamins, so you need to replenish them regularly through the foods you eat. Figure 5.1 (pg. 119) Fat Soluble Absorbed, stored, and transported in fat Your body stores these vitamins in your fatty tissue, liver and kidneys Excess build-up of these vitamins can be toxic Figure 5.2 (pg. 120) Minerals Needed for body processes (i.e.: muscle contractions, bone strength, etc.) Minerals Substances that the body cannot manufacture but that are needed for forming healthy bones and teeth and for regulating many vital processes. Calcium Phosphorous Magnesium Iron** Water Most important nutrient Most abundant nutrient 60-70% of our body 8 cups a day!!! MyPlate AHA Dietary Guidelines Amount of total calories from fat: 30% Amount of saturated fat: <10% Daily cholesterol intake: <300 mg Daily sodium intake: <2400 mg Partially Hydrogenated Fats Also known as trans fats BAD!!! Found in processed foods One pounds of fat equals 3,500 calories Calculations ** Carbohydrates and Proteins = 4 calories per gram Alcohol = 7 calories per gram Fat = 9 calories per gram Empty Caloric Food ** High in calories Low in nutrients Cholesterol Waxy, fat-like substance found in saturated fats from animal products Saturated Fats Solid at room temperature Animal sources High intake of saturated fats is associated with increased risk of heart disease Unsaturated Fats Usually liquids (oils) at room temperature Found in vegetable sources Healthier choice! Linked to reduced risk of heart disease Monounsaturated fatty acids – Liquid at room temp. but start to solidify when refrigerated Polyunsaturated fatty acids – Liquid at both room temp. and refrigerated Lipoproteins (Two Types) Low Density (LDL) Carries cholesterol from the liver to the tissues Deposits cholesterol on the lining of the arteries Dietary intake affected “Bad cholesterol” High Density (HDL) Gathers & carries excess cholesterol back to the liver Exercise affected “Good cholesterol” Fiber Indigestible complex carbohydrate Found in tough, stringy parts of vegetables, fruits and whole grains Helps move waste through the digestive system and helps prevent intestinal problems Reduces risk of heart disease May help reduce risk of diabetes 20-35 grams per day Think over your diet, what are some things you could add to it or eliminate to make it healthier? As a review of the six basic nutrients, complete pg. 71 in your WB Answer these questions: 1. 2. 3. 4. 5. 6. 7. What is an empty calorie? How many glasses of water per day? What mineral is supplied by dairy products? What is a source of complex carbs? What are fat-soluble vitamins? What is hunger? What type of fats are animals fats and tropical oils? 8. Which mineral is used to resist infection? 9. What is “bad cholesterol?” 10. What is the most abundant nutrient in the body?