Area of study 1: Understanding Australia’s health Unit 3: Australia’s health Carbohydrates A macronutrient

Area of study 1: Understanding Australia’s health Unit 3: Australia’s health Carbohydrate facts Eating one gram of CHO provides the body with 16 kilojoules of energy 55% of our energy should come from complex carbohydrates such as wholegrain cereals, fruit and vegetables. Complex CHO assist with digestion and help with disease prevention

Area of study 1: Understanding Australia’s health Unit 3: Australia’s health Carbohydrate facts Eating complex CHO will allow your metabolism to increase, which will assist in burning kilojoules If CHO are not used, they are mostly converted and stored as fat or converted into glycogen (stored inside muscle and liver) ready to boost blood sugar levels should they drop during the day.

Area of study 1: Understanding Australia’s health Unit 3: Australia’s health Carbohydrate groups There are two main groups of CHO: 1. simple sugars (monosaccharides) –From honey, fruit & vegetables –An example of a simple sugar is glucose (most soluble, easily absorbed CHO)

Area of study 1: Understanding Australia’s health Unit 3: Australia’s health Carbohydrate groups 2. complex CHO (polysaccharides) – From wholegrain cereals, fruit and vegetables (raw and skin), nuts, legumes – Examples of complex CHO are starch and fibre

Area of study 1: Understanding Australia’s health Unit 3: Australia’s health Dietary fibre There are two types of fibre – 1. insoluble fibre – is found in the structural parts of plant cell walls … fruits, vegetables, nuts and wholegrain products – has an important role in preventing constipation by producing softer bulkier faeces

Area of study 1: Understanding Australia’s health Unit 3: Australia’s health Dietary fibre 2. soluble fibre – Is found mainly in plant cells … fruits, vegetables, lentils and cereals – Soluble fibre can be important to help lower LDL (‘bad’) cholesterol levels by binding and excreting these molecules – Soluble fibre can also delay blood glucose absorption; thus regulating blood glucose levels.

Area of study 1: Understanding Australia’s health Unit 3: Australia’s health Functions of carbohydrate Carbohydrates are a major source of energy They can be used very efficiently by the body, especially systems such as the central nervous system

Area of study 1: Understanding Australia’s health Unit 3: Australia’s health Functions of carbohydrate Eating cellulose (from polysaccharides) provides the body with fibre or roughage, to speed up the metabolism and prevent constipation

Area of study 1: Understanding Australia’s health Unit 3: Australia’s health Functions of carbohydrate Fibre can therefore be a preventative/protective factor against dietary diseases such as heart disease, bowel cancer, obesity and diabetes

Area of study 1: Understanding Australia’s health Unit 3: Australia’s health Food sources Cereals and cereal products Pasta Rice Fruit Vegetables Legumes, nuts and lentils Sugar, jam, honey

Area of study 1: Understanding Australia’s health Unit 3: Australia’s health Glycaemic index (GI) Glycaemic index (GI) ranks foods according to the average time taken to reach peak blood glucose levels. Foods are given a score out of 100 and are ranked as follows: –Low GI foods (less than 55) are digested and absorbed slowly, releasing CHO gradually (baked beans, porridge, lentils) –Medium GI foods (55–70) provide an average release of CHO (chocolate, orange juice, oats) –High GI foods (greater than 70) provide a quick energy source (jelly beans, dry biscuits)

Area of study 1: Understanding Australia’s health Unit 3: Australia’s health Glycaemic index (GI) Source:

Area of study 1: Understanding Australia’s health Unit 3: Australia’s health Glycaemic index (GI) Glycaemic index is especially useful for people with diabetes who require a slow release of glucose into the bloodstream. –Individuals with diabetes do not secrete any or enough insulin to move glucose from the bloodstream and into the cells for absorption. –Low GI foods aid in slowing the release of glucose into the bloodstream, enabling diabetes sufferers to better manage their glucose levels.

Area of study 1: Understanding Australia’s health Unit 3: Australia’s health Glucose absorption This is a diagram of how carbohydrates (glucose) are absorbed in the body of healthy people. Image source: whittier.org