what are carbs n.
Skip this Video
Loading SlideShow in 5 Seconds..
What are Carbs? PowerPoint Presentation
Download Presentation
What are Carbs?

Loading in 2 Seconds...

play fullscreen
1 / 23

What are Carbs? - PowerPoint PPT Presentation

  • Uploaded on

What are Carbs?. Nutrients required by the body. What do we want to know?. What are they? Why do we need them? Are there different types? What are the best type to eat? What does GI stand for?. Carbohydrates. Formed from the word carbo (meaning carbon) and hydrate (meaning water)

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

What are Carbs?

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
what are carbs

What are Carbs?

Nutrients required by the body.

what do we want to know
What do we want to know?
  • What are they?
  • Why do we need them?
  • Are there different types?
  • What are the best type to eat?
  • What does GI stand for?
  • Formed from the word carbo (meaning carbon) and hydrate (meaning water)
  • Made up of carbon, hydrogen and oxygen molecules (carbon and water)
  • Produced by plants

through photosynthesis

But most importantly:


Provide the Body with ENERGY

They are one of the macronutrients needed by the body in order to function properly.


Why else do we need carbs?

  • Not only do Carbohydrates provide energy and heat for metabolism and activity, they also:
  • Regulate bowel movement (dietary fibre)
  • Are Essential for brain function
  • Regulate the use of fats and proteins
  • Reserve proteins for primary function
  • Glucose is the fuel of choice for active muscles as it provides heat and energy
      • To the body
how does it give us energy
How does it give us ENERGY?
  • When we eat, the body breaks down the carbohydrates to make glucose which is then absorbed into the bloodstream
  • Glucose = Fuel for our Bodies (1g CHO =16kJ)
  • A lot of carbohydrates also contain vitamins and minerals that help keep us in tip-top shape and health
simple carbohydrates
Simple Carbohydrates
  • Have short chains of molecules so dissolve quickly

Eg. glucose, fructose, galactose

Foods include:

Cakes Honey

Softdrink Syrups

Lollies Sugar


Some fruits (grapes)

disaccharides double
Disaccharides (Double)
  • When you have a joining of 2 monosaccharides

Eg. Sucrose, Maltose, Lactose

Foods Include:

Sugar cane



complex carbohydrates
Complex Carbohydrates
  • Have Long Chains of molecules and take longer to dissolve

Eg. starch, dextrin, pectin, cellulose, glycogen

Foods include:




Fruits and vegetables

how much do we need
How much do we need?
  • Medical experts say that 45 - 60% of our diet should be made up of carbohydrates
  • Average intake for a teenager should be about 8700 kilojoules per day

So, 8700 x 60 % = 5220 kilojoules

1 gram of carbohydrates = 16 kilojoules

So, the RDI (Recommended Daily Intake) is approximately 310g of carbohydrates per day

how do i get enough
How do I get enough?

To help get the right amount of carbohydrates in your diet, try to include 2 serves at each meal.

An example of a serve is:

2 slices of bread

1 cup cooked rice

1 1/3 cups cereal

1 medium piece of fruit

1 tub of low fat yoghurt

250ml glass low fat milk

Remember, a balanced diet is a healthy diet!!!

how do i know how many carbohydrates a food contains
How do I know how many carbohydrates a food contains?
  • There is lots of information around: in books, on the internet, health practitioners
  • All packaged foods must have labels to let us know what they contain

Let’s have a look at a few

common foods and the

carbohydrates they


basic foods
Basic Foods

We could use Food Composition tables to analyse our diets.

what is gi
What is GI?
  • A ranking given to food that describes how quickly the carbohydrates they contain will be digested (changed to glucose) and absorbed into our bodies


High GI foods are digested and absorbed quickly

Low GI foods are digested and absorbed slowly

low v s high
Low V’s High

Low GI Foods

High GI Foods

  • Keep you feeling full for longer as they provide a gradual supply of energy
  • Helps keep blood glucose levels stable
  • May help to prevent some diseases
  • Used when high energy levels are needed for shorter bursts

Eg. athletes, sports people

body builders

dietary fibre another kind of carbohydrate
Dietary FibreAnother kind of Carbohydrate

As if the humble Carbohydrate didn’t already have a big enough job!!!!

It also provides our diet with fibre – a carbohydrate that only comes from plant based foods (fruits, vegetables and grains)

Fibre in food is tough and stringy and our bodies won’t break it down completely so it helps to ‘regulate’ us

RDI of Fibre is 25 – 30g

Best Fibre options:

Wholemeal or Grain Breads, Bran, Fruit

and Vegetables, nuts, seeds, popcorn

functions of dietary fibre
Functions of Dietary Fibre
  • Stimulates chewing and encourages saliva flow to ensure healthy gums and teeth and more efficient digestion
  • Inhibits the emptying process of the stomach, therefore satisfying hunger for longer
  • Controls the rate of glucose absorption into the blood by slowing down the digestion of nutrients
  • Softens faecal waste to ensure comfortable bowel actions
effects of dry and moist cookery methods
Effects of dry and moist cookery methods
  • Dry heat of sugar causes caramelisation.
  • When boiled, sugar dissolves in water and then becomes a syrup. As water evaporates it caramelises and eventually burns.
  • Starch dissolves, swells and bursts when heated in water/liquids.
  • Dry heat causes starch cells to burst e.g. popcorn, pastry.
  • When dry heat is applied to starch shorter chain polysaccharides are formed, these are called dextrins (toasting).


  • provide the body with ENERGY
  • good source of fibre
  • good source of vitamins
  • 3 different types:
    • Monosaccharide (simple/sugar)
    • Disaccharide (double)
    • Polysaccharide (complex/starch)
  • The Glycaemic Index tells us how long the ‘energy’ from carbohydrates will stay in our body