A healthy diet

A Healthy diet.notebook

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November 05, 2012

A Healthy DietTopics covered:

• Nutrients needed by the body• How the body uses different nutrients• The nutrient content of different foods• A balanced diet• Malnutrition• A plan for a healthy diet


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November 05, 2012

Starter:

• No breakfast• Eat sweets on the way to school• Eat chocolate and Inca cola at break• Have fries and hamburger for lunch• Eat more sweets in afternoon• Avoid green vegetables in evening meal• Drink mainly pop such as cola

Diet 1

• Eat cereal or toast for breakfast• Eat fruit at break• Have a variety of foods for lunch, such as vegetables, rice or pasta.• Eat more fruit in the afternoon• Eat green vegetables in evening meal• Drink juices or water

Diet 2

• Write a description of what you eat during a typical day• Compare your pattern with the two diets below• Which diet does yours match more closely?• From what you already know, try to explain which diet shown is

healthier


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November 05, 2012

Nutrients

Are chemicals needed by the body to keep it in good shape

• Carbohydrates• Fats• Proteins• Vitamins• Minerals

(also, the body needs about 70% water, and fibre is also needed)


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November 05, 2012

Carbohydrates

Made from the following elements; carbon, hydrogen, oxygen

= a sugar molecule, containing C, H and O

The most common sugar is glucoseGlucose will form long chains such as starch

Glucose in plants forms chains called cellulose


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November 05, 2012

Fats

Made from lots of carbon and hydrogen Has some oxygen

There are two basic types; solid fats in animals, and liquid oils in plants


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November 05, 2012

Proteins

Made from carbon, hydrogen, oxygen and nitrogen

C, H, O and N form amino acidsSometimes, sulphur is present

= amino acid

Amino acids join together to form protein molecules


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November 05, 2012

Vitamins

Needed in small amountsAt first they were given alphabetical names, later chemical names

Minerals

We need 20 different minerals, some in large amounts such as calcium. some are needed in small amounts and are called trace elements

Read the descriptions of each nutrient on pp 24 - 26


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November 05, 2012

What does our body do with these nutrients?

Read the descriptions for each type of nutrient and then match the description to the word

Fibre

Proteins

Minerals

I contain cellulose from plant cell walls. I am undigestible and allow the food to be pushed through the intestines.

I am used for building structures inside cells. I am needed for growth and repair. Some of us that speed up reactions are called enzymes

We make bones and teeth strong. Others help blood to take up oxygen properly.

Plenary


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November 05, 2012

I help cell membranes to form properly. I also provide energy and also insulate, keeping the body warm.

We help in many tasks, such as helping the eyes to work better or stopping scurvy or allowing bones to take up calcium.

I provide energy for the body and can be released quickly.

I am something very important. You could only live a few days without me! I also help you cool down!

Fats

Water

Carbohydrates

Vitamins


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November 05, 2012

Are all foods the same?

Objective:

Know that foods contain different amounts of nutrients

Starter:

Answer the following question: Why must we eat a variety of foods?


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November 05, 2012

Malnutrition

What does the word 'malnutrition' mean to you?

All foods contain different amounts of nutrients. In groups, answer questions 11 - 26.

Prepare your answers for class disussion


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November 05, 2012

A healthy diet

Design a pyramid of food that represents your diet from the packaging you brought in.

How does your pyramid of food compare with the one shown on page 33?

What things are needed for a diet to be considered 'healthy'?


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November 05, 2012

Fats

Carbohydrates

Proteins

Fibre, Vitamins and minerals

A Healthy diet

More

Less

Use the summary on page 34 to review your work

Extension: Answer questions 1 and 2 on page 35.

Plenary:


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November 05, 2012

Vitamins and their uses

Vitamin Effect on body Good sources

A

increased resistance to disease. Helps eyes to see in

the dark

milk, liver, cod-liver oil

B1

Prevents digestive

disorders and prevents a

disease called beriberi.

bread, milk, brown rice, soyabean,

potato

C

Prevents the disease called

scurvy an which gums bleed and the circulatory

system is damaged

blackcurrant, orange, lemon, papaya, guava

D

Prevents the disease rickets in which bones become soft

and leg bones bend

egg yolk, butter, cod-

liver oil, pilchard, herring, sunlight


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November 05, 2012

Foods and their nutrient content

Objectives:

• Know what nutrients foods contain• Know how to test for nutrients


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November 05, 2012

Group the following foods for the nutrient contained

Foods and their nutrient content

Protein Carbohydrate

Fat

Starter


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November 05, 2012

How do we know what nutrients are in food?

We know what to eat, but how do we know?

Food testing

Nutrient Test

Protein Biuret's reagent

Carbohydrate (starch) Iodine solution

Carbohydrate (glucose) Benedict's solution

Fat Ethanol

In the last activity, you were asked to place the foods into groups for just one nutrient. Foods contain more than one type of nutrient.


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November 05, 2012

Protein - Biuret's reagent

Blue solution Lilac solution

If protein is present, Biuret's reagent will turn lilac

- ve +ve

Carbohydrate (starch) - iodine solution

If starch is present, Iodine will turn Dark blue/purple

Orange solution Dark blue/ purple

+ve- ve


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November 05, 2012

Carbohydrate (Glucose) - Benedict's solution

If reducing sugar is present, Benedict's solution will change colour

0 1 2 3 4least most

Fat (lipid) - Ethanol

If fat is present, ethanol will form a cloudy solution

Clear ethanol Cloudy ethanol

ethanol and fat ethanol and fat


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November 05, 2012

Food testing

You are going to carry out a series of tests on food to find out what nutrients they contain.Follow the instructions and record your data in a suitable table.

Method:

• Take a sample of food • Test the food for protein, starch, sugar and fat• Record the results in the table• Repeat for the other foods available


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November 05, 2012

Food Test Observation Meaning

Fish

Protein

Starch

Glucose

Fat

Results:


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November 05, 2012

Plenary:

The following diagram is called a Venn diagram. Use this to group the food into three main food groups, placing sugar and starch together.

Protein Fat

Carbohydrate


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November 05, 2012

Food Protein Starch Glucose Fat

Fish

Cheese

Milk

Egg

Butter

Cracker

Bread

Fruit

Ham

7 up

Results: Overview sheet

Homework:

Use the information from this lesson to revise for a test on food tests. You will need to be able to explain the test and what the results mean.

e.g. 1. What is the test for starch?2. a food was tested for starch and the iodine solution

turned black. What does this result mean?


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November 05, 2012

Look at the following people and decide what types of food they will need to eat in their diet:

Extension activity

Eskimo Athlete

BabyOld age pensioner


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November 05, 2012

Activity: High, long distance cyclingLiving conditions: mild

Teenager

Body builder

Officeworker


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November 05, 2012

Homework for 1F

You are a chef who is going to make a menu for a 4- day school field trip for students. The trip will involve a lot of walking and sports activities.

The menu will need to have • breakfast • lunch • dinner

It will need to be balanced and contain all the nutrients needed.


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November 05, 2012

Documents

A healthy diet