Nutritional Needs

Introduction to Chapter 2

Chpt. 2 Objectives

• Name key nutrients, describe their functions and sources

• Analyze effects of nutrient deficiencies and excesses

• Explain the process of digestion

Nutrients for Good Health

• Nutrient: chemical substance in food that helps maintain the body– Eating too many sweets and fats, skipping meals

prevent us from getting all of the nutrients we need

• Nutrition: study of how your body uses the foods you eat

• Malnutrition: lack of the right proportions of nutrients over an extended period of time– Causes: body’s inability to use nutrients in food, body

does not receive adequate nutrients

Nutrients for Good Health, Con’t

• The amount of food is not as important as the right variety of food!

• A person who is malnourished could be overweight or underweight

• Some effects of malnutrition are longlasting– What a girl eats now could effect her pregnancy later– Foods pregnant women eat can affect their child’s

growth and development in the future– Lifespan and health can be affected in the long run

Nutrients!

• You need over 50 nutrients for good health!

• Nutrients supply energy, build and maintain body and cells and regulate bodily processes

• No single food supplies all of the nutrients!• All nutrients fall into six groups!

– Carbohydrates, Fats, Proteins, Vitamins, Minerals and Water

Nutrients! Con’t.

• A healthy diet contains nutrients from all six groups in the right proportion

• Failure to meet nutrient needs results in a Deficiency Disease: illness caused by lack of sufficient amounts of a nutrient

• To meet nutrient needs• Dietary supplements: purified nutrients

that are manufactured or extracted from natural substances

Carbohydrates

• Body’s chief source of energy!• Three main types of carbohydrates• Simple Carbohydrates

– Sugar• Complex Carbohydrates

– Starches– Fiber

• Most Carbohydrates come from plant foods• Glucose: form of sugar carried in the blood stream for

energy use throughout the body• Fiber: form of complex carbohydrate that humans

cannot digest– Does not provide the body with energy– Helps you to feel full and promotes normal bowel function

Fats

• Important energy sources• Belong to a larger group of compounds called lipids• Lipids: include both fats and oils, all lipids contain fatty

acids• Fatty Acids: chemical chains that contain carbon,

hydrogen and oxygen• Saturated Fatty Acids: fatty acids that have as many

hydrogen atoms as they can hold• Unsaturated fatty acids: have fewer hydrogen atoms as

they can hold– Monounsaturated fatty acids: missing one hydrogen atom– Polyunsaturated fatty acid: missing two or more hydrogen atoms

Fats Con’t

• Most Fats high in saturated fatty acids are solid at room temperature

• Oils high in unsaturated fatty acids are liquid at room temperature

• Hydrogenation: adds hydrogen atoms to unsaturated fatty acids in liquid oils– Margarine– shortening

• Trans Fatty Acids: fatty acids with odd molecular shapes. When oils are partially hydrogenated trans fatty acids are created– Creates health concern!

Fats Con’t

• Cholesterol: fat like substance found in every cell of the body

• Serves several important functions:• Part of skin tissue• Aids in transport of fatty acids• Body needs it to produce hormones

• 2 types: Dietary Cholesterol and Blood Cholesterol

• Dietary cholesterol: occurs when you eat “animal” foods

• Blood Cholesterol: circulates through your blood stream– A high blood cholesterol level can lead to heart

disease

Proteins

• Chemical compounds that are found in every cell of the body

• Made up of small units called Amino Acids• 9 amino acids are essential amino acids• The body can not make essential amino acids• Complete proteins contain all 9 essential amino

acids• Animal foods and soybeans have complete

proteins• Most plant foods have incomplete proteins

Assignment• “Big Three” Nutrient ProjectUsing one sheet of paper for each nutrient, list the following

information:• Name of nutrient( carbohydrate, protein, fat)• Function of nutrient• Pictures of food sources: Carbohydrate- Complex (2), Simple (2) Protein- Complete (2), Incomplete (1) Fat- (2) Label what type of fat-saturated,

polyunsaturated, or monounsaturated

NEATNESS COUNTSDUE 9/12/08