Chapter 15.1Why do we eat &Nutrition and Nutrients

Why do we eat? Physical Needs:

Nutrients—chemicals found in food, the body needs to function properly.

Nutrition—study of foods and the way your body uses them.

Why do we eat?, cont. Psychological Needs:

Security—knowing your basic needs are met.

Sense of belonging —hospitality, being together as a family.

Enjoyment—learning how to cook or going out for a meal.

Self-esteem—satisfaction gained when cooking.

Influences on Food Choices Social Influences:

Culture—shared customs, traditions, beliefs

Family—tied to culture Friends—friends help us choose what to

eat Media—TV ads for Food trigger what we

eat

Influences on Food Choices Resources: objects or qualities that help

us reach a goal Time, money, knowledge, abilities Technology--equipment Food Supply—what fresh food is available

for us.

Influences on Food Choices Personal Influences:

Your Lifestyle—our way of life Values and Priorities—home cooked meals

or eating out Emotions—we eat when we are sad --we eat when we celebrate

Nutrients There are 50 known nutrients we divide them into 6 major nutrient

groups: proteins (contain calories) carbohydrates (contain calories) fats (contain calories) minerals vitamins water

Carbohydrates Function: Main source of energy Types:

Complex carbohydrates – starches Sources: cereals, breads, vegetables

Simple carbohydrates – sugars Sources: sugars, syrup, molasses, honey

Fiber – a kind of complex carb No energy supplied but needed for digestion and

elimination Sources: fresh fruits and vegetables, whole grains

Proteins Function: Build and repair body tissues Made from small chemical units called

amino acids there are 22 amino acids all are made by the body except for 9

(known as essential)

Proteins cont. Types

Complete - found in animal sources Sources: meat, poultry and fish

Incomplete - found in plant sources Sources: whole grains, nuts, and dry beans.

Fats Function: Helps body digest food, keep

body temp. normal, and store and use fat-soluble vitamins, protect vital organs

Sources: butter, margarine, lard, oils, meats, fish, nuts/seeds

Types of Fats Saturated fats: solid at room temp.

Source: butter & lard Unsaturated fats: liquid at room temp.

Source: oils Trans Fats – turn liquid oils into solid –

hydrogenation Source: margarine

Cholesterol: fatty substance found in your cells. Source: ONLY in animal sources

Cholesterol Friends with protein Remember: liver naturally makes

cholesterol, limit your intake in food sources

Two kinds of cholesterol: HDL – good cholesterol, captures

cholesterol and takes it to the liver LDL – bad cholesterol, build up in the

artery walls and cause clogs

Minerals Function: Chemical substances your body needs

to work properly. Types

“Major” minerals— body needs large amounts. Calcium, phosphorus, iron

“Trace” minerals-- body needs small amounts. Zinc, iodine, fluorine

“Electrolytes” – work to balance fluid levels Sodium, Potassium, Chloride

Minerals Calcium (major)

most abundant mineral in the body provides strong bones and teeth Osteoporosis – severe shortage of calcium sources: milk and milk products, leafy grn veg

Phosphorus (major) Second most abundant mineral helps bones and teeth form found in dairy products

Minerals Iron (major)

Helps build red blood cells and to carry oxygen

sources: red meats, liver deficiency results in anemia—fatigue, pale skin, poor

ability to resist infections anemia affects 1/4 of American population, mostly

teenage girls Magnesium (major)

Build bones, nerves and muscular system, proper heart function

Sources: whole grains, dark green leafy veggies, nuts/seeds

Minerals Fluorine (trace)

prevent tooth decay Toothpaste, tap water

Iodine (trace) makes thyroid gland work correctly Lowers risk for goiter found in iodized salt and saltwater seafood

Minerals Zinc (trace)

Helps the immune system work properly and helps wounds heal.

Helps the body to digest iron Too little will stunt your growth Sources: protein foods

Sodium (electrolyte) Works together with chlorine and potassium. Helps maintain balance of fluids in the body. Sources: table salt, packaged foods, cheese

Minerals Potassium (electrolyte)

Helps to balance fluid levels while working with water, sodium and chloride

Sources: found in bananas, oranges, dried fruits, peanut butter

Vitamins Function: to keep the body healthy and

assist with the use of minerals Needed in small amounts in the body Vitamin supplements are not always

absorbed by the body, eat a variety of foods instead

Two types: Fat soluble – absorb and transported by fat Water soluble – absorb and transported by water

Vitamins Vitamin A (fat soluble)

needed for good vision sources: dark green or deep yellow

vegetables (carrots), liver, egg yolks Carotene: orange pigment from foods

that the body can convert to Vitamin A Vitamin K (fat soluble)

helps blood to clot Sources: dark green leafy vegetables

Vitamins Vitamin D (fat soluble)

“Sunshine Vitamin” helps body use calcium and phosphorus to

build strong bones and teeth Helps prevent rickets – softening of bones sources: fortified milk, sun

Vitamin E (fat soluble) makes red blood cells and keeps body strong sources: milk, egg yolk

VitaminsB-Vitamins (water soluble)

group of vitamins important for nerve and brain tissue to develop and function well

B-Vitamins Thiamin (B1)

Promotes normal appetite and digestion. Deficiency causes Beriberi. – glucose digestion Sources: Pork

Riboflavin (B2) Helps cells use oxygen. Sources: Milk products

B-6 Helps control metabolism and blood sugar Shortage has been linked to depression and high blood

pressure Sources: meats and whole grains, vegetables, bananas, nuts

B-Vitamins Niacin (B3)

Keeps nervous system healthy. Deficiency causes Pellagra. Source: Whole grain products

Folate- (folic acid) – (B9) Important in the development of the spine and brain

in unborn babies. Source: whole grain products

Vitamin B-12 Helps body make red blood cells and protects nerves. Source: fish, shellfish, poultry, eggs, milk products

Vitamins Vitamin C (ascorbic acid) – water soluble

Function: fights infection, heals wounds and cuts

good sources--citrus fruits, dark green leafy vegetables, strawberries, tomatoes

Phytochemicals Substances that plants produce naturally to

protect themselves from harm Give many foods their color Help prevent cancers and heart disease Examples: Lycopene, carotene

Water Makes up 2/3 of your total body weight Carries nutrients to cells regulates body temperature Moistens nasal passages basic material of blood, is in all cells should have 8-12 glasses of water a day Dehydration – extreme lack of water