Core Topic 1: Fundamentals of
Human Nutrition
Overview of Topic 1
1.1 Humans need essential nutrients for good health:
 Investigate why humans must include essential nutrients in their
diet.
 Analyse how macronutrients and micronutrients function and
their relationship to optimal wellbeing.
 Investigate the relevance of Acceptable Macronutrient Distribution
Ranges (AMDR) and develop skills to compare percentage
requirements.
 Understand and investigate how foods can be combined to improve
their nutritional status.
Macronutrients - Carbohydrates
 Found in plants and created
through the process of
photosynthesis.

When plants use energy from the sun
to combine CO2 and water from the
environment to form carbohydrate.
 Carbohydrates are made up of
Carbon, Hydrogen and Oxygen;
thus, carbohydrates are
abbreviated as CHO.
Why do we need Carbohydrates?
 The body requires
carbohydrates to:

Provide the body with heat
and fuel to perform daily
activities (1g = 16kj)

Provide dietary fibre to
stimulate the digestive system

The regulation of protein and
fat use by the body
Carbohydrate Classification
Monosaccharide
Carbohydrates
Disaccharide
Polysaccharide
Monosaccharide
 Simple sugars
 There are three forms of monosaccharides:
 Glucose
Most carbohydrates are converted to glucose by the digestive
system
 Easily absorbed and used for energy
 The body’s preferred source of fuel
 Sources include ripe fruits, some vegetables and honey


Fructose (fruit sugar)


sources include fruit and honey
Galactose

formed during the digestion of lactose (milk sugar)
Disaccharide
 Disaccharides contain two
monosaccharide units.
 Disaccharides include:
 Sucrose (glucose + fructose)


Lactose (glucose + galactose)


Found in cane sugar, fruits and some
vegetables
Found in dairy products
Maltose (2 molecules of glucose)

Found in germinating grain crops
Investigation Skills
1. Name the graph.
2. Interpret the findings
Polysaccharide
 Monosaccharides can be joined together in long chains
called polysaccharides.
 Polysaccharides include:
 Starch


Found in cereals including wheat, rice
and corn, cereal products including rice and
pasta and vegetables including potato and peas.
Glycogen
Stored in the liver and muscles
 Can be converted back to glucose

Polysaccharides
 Pectin
(soluble)
 Found
in seeds, pith and peel of
fruits and vegetables.
 Digested by intestinal bacteria.
 Attracts water and turns to
gel during digestion
 May help reduce cholesterol
 Allows nutrients to be
released more slowly
 Contributes to a feeling of
satiety
Polysaccharides
 Cellulose
(dietary fibre –
insoluble)
 Forms
in the cell walls of plants
 Partly digested
 Adds bulk to the stool
 Appears to help foods pass
quickly through
the stomach and intestines
 Contributes to a feeling of
satiety
How much Carbohydrate?
 1g of carbohydrate yields 16kj of energy.
 45-65% of the total daily energy intake should be
from Carbohydrates.

For example if the total energy intake is 8,000kj, then 3,6005,200kj should derive from carbohydrates.
Carbohydrate Deficiency and Excess
Symptoms of deficiency
Symptoms of excess
• Fatigue
• Inability to exercise (no glycogen)
• Headaches
• Fainting
• Lack of vitamins and minerals
• Low dietary fibre intake – constipation
• Protein depletion
• Dental caries (decay or cavity) build up
of plaque, which sticks to acids in our
mouth. The acid eats away at the
outermost layer of the tooth called the
enamel.
• Weight gain – increase in adipose
tissue
Dietary Fibre
Indigestible
Insoluble
Digestible
Soluble
 Fibre is grouped into two types:
 Soluble – digested by intestinal bacteria


legumes, oats, barley and fruits
Insoluble –partly digested

Vegetables, grains, cereals and seeds
Why is Fibre Important?
 Fibre is important in the diet because it:
 Slows down initial digestion for nutrients to be released into
the body slowly; thus, the absorption of vitamins and minerals
is maximised.
 Helps produce soft, bulky stools, which are easy to expel from
body.
 Provides a feeling of fullness in the stomach – thus reduces
obesity.
 Increases the transit time of stools through intestines; thus,
prevents constipation, diverticular disease, bowel cancer,
haemorrhoids and potentially varicose veins.
What is the graph depicting?
1. Name the graph.
2. Interpret the results.
Why is Fibre Important?
 Fibre is important in the diet because it:
 Slows down initial digestion for nutrients to be released into
the body slowly; thus, the absorption of vitamins and minerals
is maximised.
 Helps produce soft, bulky stools, which are easy to expel from
body.
 Provides a feeling of fullness in the stomach – thus reduces
obesity.
 Increases the transit time of stools through intestines; thus,
prevents constipation, diverticular disease, bowel cancer,
haemorrhoids and potentially varicose veins.
The Glycaemic Index (GI)
 ‘The speed at which a
carbohydrate food breaks down
into glucose has been studied
and the foods have been
ranked.’ (Queensland Government 2011)
 The amount and type of sugar
in a food will impact a food’s
GI.
Glycaemic Index (GI)
Low = < 55%
Intermediate = 55-69%
High > 70%
Milk
Yoghurt
Nuts
Beans
Pasta
Weet Bix
Brown Rice
Soft drinks
Brown rice
Sucrose
French fries
White bread
Jelly Beans
Water melon
Rice crackers
Glycaemic index (GI)
Low GI diets:
 help diabetics control glucose
tolerance
 can reduce total cholesterol
and triglyceride levels,
increase HDL, reduce blood
clotting and risk of CVD
 are more filling and can aid
wait control
Structure of a Extended Response Question
 Usually written in three of four parts. Ensure you address
each dot point.
 This section must be written in continuous prose. NO
DOT POINTS !
 Definitions should be given where possible.
 Give yourself time to structure your response.
 Use relevant explanations and examples to support your
response.
Extended Response Question
 Polysaccharides are better for us than
monosaccharides and disaccharides.




Define monosaccharides, disaccharides and polysaccharides.
Discuss the significance of polysaccharides for human beings.
Outline concerns if a person does not consume sufficient
Polysaccharides.
Outline dietary strategies to boost one’s intake of
polysaccharides.