NutritionWhat is nutrition?• the science of how the foods

you eat affect your body

What are nutrients?• substances that nourish your

body• Six categories of nutrients:

• Carbohydrates• Proteins• Fats• Vitamins• Minerals• Water

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Carbohydrates• function: the body’s main source of energy• two categories: simple and complex

Simple Carbohydrates• composed of one or two sugar units• foods with LOTS of sugar: oranges and milk

contain natural sugars; cookies and candy are high in added sugar

Carbohydrates

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Complex Carbohydrates• starches that are composed of many

sugar units linked together

• your body breaks down starches into smaller sugar units that are used for energy

• foods with LOTS of starch: rice, beans, potatoes

• many foods high in starches also supply fiber (helps your digestive tract work properly and may help protect against heart disease and cancer)

Carbohydrates

• 9 of the 20 amino acids are called essential amino acids because you must obtain them from the foods you eat since your body cannot make them.

Proteins

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Proteins• Structure: Proteins are

made from many amino acids connected together in different arrangements

• Function: help your body grow, repair itself, and fight disease

Complete proteins: • foods containing all the essential amino acids

Examples: fish, meat, eggs, milk, cheese

Incomplete proteins: • foods that are missing some essential amino acids

Examples: dry beans and peas (legumes), nuts, whole grains

Proteins

Functions:• promotes healthy skin and normal

growth• carries vitamins to wherever your body

needs them• helps protect and cushion vital organs

as well as joints • insulates the body

There are two types of fats: saturated and unsaturated

Fats

Unsaturated fats: • at room temperature, they are

typically in liquid form.

• they are less harmful to the circulatory system than saturated fats.

• foods with a lot of unsaturated fat: vegetable oils, nuts, olives, avocados

Fats

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Saturated fats: • at room temperature, they are

typically in solid form

• diets with TOO MUCH saturated fat tend to raise the level of cholesterol in your blood, which increases your risk for heart disease

• foods with a lot of saturated fat: butter, meats, poultry, some dairy products

(Cholesterol is a waxy substance found in foods from animal sources)

Fats

Vitamins• they regulate body

functions by helping other nutrients do their jobs

• there are two main categories: water-soluble and fat-soluble

VitaminsWater-soluble vitamins•excess vitamins are excreted with the urine•taking large amounts of these vitamins from supplements overworks the kidneys and may cause damage

•ex: vitamins B1, B2, B3, folic acid, vitamin C

Fat-soluble vitamins•stored in liver and fat until you need them•excess amounts can build up to harmful levels•ex: vitamins A, D, E, K

MineralsFunctions:• regulates body processes• give structure to bones and teeth• provide materials for healthy blood and tissue

examples: calcium, phosphorus, magnesium, and iron-calcium, phosphorus, and magnesium help build and maintain your bones over your lifetime-iron helps red blood cells carry oxygen to all your body’s cells

WaterFunctions:• regulates body temperature• transports nutrients to body cells and carries waste products away• aids in digestion• moistens body tissues such as eyes, mouth, and nose• cushions your joints• protects your body organs and tissues

• You need a regular supply of water to help your body perform its many life-supporting activities (aim for 8 cups a day)

• essential to life – you can only live a few days without water