Nutrients Chapter 36

What are nutrients?? Nutrients—chemicals found in food that help the body work properly Needed to maintain good health and fight diseases More than 40 are identified Each has specific jobs

Nutrients Six Classes: –Carbohydrates –Proteins –Fats –Water –Vitamins –Minerals

CARBOHYDRATES

Carbohydrates Carbohydrates—the nutrients that provide your body with ready energy Grains, vegetables, fruits, and dry beans and peas Body’s most efficient fuel You need them throughout the day Sugars and starches are the 2 main types

Starches Complex carbohydrates Rice, potatoes, bread, and pasta Starch is digested to form a simple sugar called glucose, which is a major source of energy for your body

Sugars Glucose can be formed from sugars (simple sugars) Fruits, grain products, and milk Sugar removed from it’s natural source and processed is refined sugar –Cakes, cookies, processed foods –Too much leads to weight gain and dental problems –Causes problems for people with diabetes

Fiber Fiber—indigestible threadlike cells Not strictly a nutrient, but performs several important jobs Helps move food through the digestive system Reduces the risk of heart disease Whole grain cereals, breads, fruits, vegetables (especially the peels and seeds)

PROTEINS

Proteins Proteins—nutrients necessary for building and repairing body tissues Basis of all the body’s cells and form the major part or hair, nails, and skins Especially important for children and teens, because they are growing

Complete & Incomplete Proteins Amino acids—chemicals in proteins –22 have been identified 9 must be obtained from food (essential amino acids) –Also called complete proteins –Animal proteins: meat, poultry, fish, eggs, and milk 13 can be combined with other food sources –Dry beans & peas, nuts, seeds, vegetables, grains –Incomplete proteins (contain some but not all of the essential amino acids)

FATS

Fats Fats—nutrients that are the most concentrated sources of energy Needed by the body –To transport and store certain other nutrients –Regulate body temperature and growth Without dietary fats, people can develop skin and hair problems

Fats After the body uses the fat it needs, it stores the rest as body fat –Some is needed to insulate the body, protect vital organs, and serve as a supply of energy –Eating too much over a period of time, will make you gain weight Leads to heart disease and other serious problems –Present in many foods Butter, margarine, sour cream, fried foods, salad dressings

Saturated and Unsaturated Fats Saturated Fats –Found in animal foods such as meat, milk, butter –Solid at room temperatures –Undesirable because they lead to high levels of cholesterol in the blood White, waxlike substance that plays a part in transporting and digesting fat –Leads to heart disease, high blood pressure

Saturated and Unsaturated Fats Unsaturated Fats –Found in oils from vegetables, nuts, and seeds –Liquids at room temperature –Healthier for you!!!

WATER

Water 70% of your body weight Found in every cell and is the basic material of your blood Transports nutrients throughout the body and carries away waste products Helps to move food through the digestive system to regulate the temperature of your body Milk, soups, fruits, vegetables Drink 6-8 glasses of water daily

VITAMINS

Vitamins Vitamins—nutrients that help the body stay healthy, function properly, and process other nutrients Do not provide energy or form body tissues, but are necessary for good health Needed in very small amounts Not getting enough can lead to eye, skin, and bone disease Either water soluble or fat soluble

Water Soluble Water soluble vitamins—easily absorbed and can move through the body dissolved in water Need fresh supplies of these vitamins daily since water is constantly lost out of our bodies in sweat and perspiration Excess amounts are NOT stored for future use Vitamin C & B vitamins

Fat Soluble Vitamins Fat soluble vitamins—travel through the bloodstream in droplets of fat Can be stored in fat cells for long periods of time Vitamins A, D, E, & K

MINERALS

Minerals Minerals—simple substances that form part of many tissues and are needed to keep body processes operating smoothly Body contains large amounts of some (calcium) and tiny amounts of others (iron) –Needed during adolescence because of the increase in growth –Calcium—bone growth –Iron—red blood cells

Nutrients and Calories The energy in food is measured in calories—unit of heat energy –# of calories in a food is the amount of energy the food provides –Energy can be used or stored as fat –Calorie count depends on nutrients a food contains 4 calories for each gram of protein 4 calories for each gram of carbohydrates 9 calories for each gram of fat Water, vitamins, and minerals have NO calories!!! 55% of daily calories need to come from carbohydrates