Carbohydrates Flashcards
What are the functions of Carbohydrates?
- Providing energy
2. Acting as a ‘protein sparer’
What does protein sparer mean?
It mean it allows protein to do it’s job and carbohydrates to do their job
What are the 3 types of Carbohydrates?
- Sugars
- Starches
- Dietary Fibre
Is Sugars simple or complex?
Simple
Is Starches simple or complex?
Complex
Is Dietary Fibre simple or complex?
Complex
What are Sugars and how how are they divided?
Sugars are divided into single and double sugars depending on the size of the molecule
Are sugars easy to break down?
Easy to break down = burst of energy
What are single sugars?
Single sugars are monosaccharides meaning they only contain one single molecule
What chemicals are single sugars found in?
In Glucose and Fructose
Where could single sugars be found in food?
- In ripe fruits and vegetables
2. Fruits and honey
What are double sugars?
Double sugars are made up of disaccharides meaning they are made up of 2 molecules
What are some chemical examples of double sugars?
Sucrose, lactose and Maltose
Where food can double sugars be found?
- In sugar and syrup
- Dairy
- Cereals
What are the 2 different types of sugar?
- Free
2. Fruit
How are sugars categorised into free or fruit?
Sugars can be named based on where they’re found
Where are fruit sugars found?
Natural sugars from fruit and vegetables = Fruit sugars
What are free sugars?
Sugars that are added or outside the cell structure = free sugars
What food products are free sugars found in?
- Granulated sugar
- Syrup and treacle
- Honey
- Unsweetened fruit juice
What do fruit sugars contain that is good for you?
- Fibre
- Vitamins
- Minerals
- They’re enclosed in the cell wall which means the body has to process the sugar making it good for your body
Why are free sugars bad for you?
- All the nutrients are squeezed out
2. Not good for you as the body doesn’t have to process it as it’s not inside the cell wall
What are hidden sugars?
Sugars that are found in foods that you wouldn’t expect, including savoury foods.
What are some chemical examples of hidden sugars?
- Corn sugar
- Dextrose
- Molasses
- Fructose
- Maltose
- Glucose
What are some product examples of hidden sugars?
- Ketchup
- Pizzas
- Bottled cooking sauces e.g pasta
- Baked beans
- Tomato soup
- Low fat yogurht
What can high levels of sugar lead to?
- Tooth decay
2. Obesity
Why is sugar particularly not useful in your diet?
Sugar contains energy but no other nutrients - empty calories
Why are artificial sweeteners good?
Artificial sweetness adds sweetness without increasing the energy content or calories
What are starches also known as?
- A complex carbohydrate
2. A Polysaccharide meaning many sugars
What are the 3 most important starches?
- Starch
- Pectin
- Glycogen
What are some properties of starch?
- Main food store in plants
- Made up of many glucose molecules
- size of granules vary with each plant
What are some properties of pectin?
- Found naturally in some fruits
- Forms a gel in water and helps jams to set
- Is thought to reduce cholesterol in the blood
What are some properties of Glycogen?
- Made from glucose by humans
* Small amounts stored in liver and muscles as energy reserve
What are some food sources of starch?
- Root vegetables e.g Potato, carrot, parsnip, onion
2. Cereals and cereal products e.g wheat, flour, bread, pasta, oats
How much of our energy should come from carbohydrates?
• 50% of total food energy should come from carbohydrate
How much of the 50% of carbohydrate should come form starchy carbohydrates?
45% of your total energy should come from starchy carbohydrates, milk sugars and fruit sugar
How much of the 50% of carbohydrate should be free sugars?
– No more than 5% of your total energy should come from free sugars
What are some deficiencies from not enough starches?
- Unusual
- Lack of energy – drop in level of glucose in blood
- Weight loss – body will start to use fat stores if continued
- Severe weakness – if fat stores depleted, then protein stores used
What can an excess of starches lead to?
• If not used = converted into fat and stored in body.
• Could lead to obesity
• Obesity could lead to other health issues: – Increased risk of type 2 diabetes
– Cardiovascular disease
What is dietary fibre?
- Is a polysaccharide(manysugars)
* AKA non-starch polysaccharide (NSP)
What food can dietary fibre be found in?
– Wholegrain cereals and products e.g. brown rice, wholemeal flour
– Fruits and vegetables
– Pulses e.g. beans, lentils
What are the functions of dietary fibre?
- For a healthy digestive system
- Weight control
- Prevents bowel disease:
– Constipation
– Diverticulitis
– Bowel cancer - Providing soluble fibre (and lower blood cholesterol)
What are the 2 types of fibre?
- Soluble
2. Insoluble
What are some of the benefits of soluble fibres?
- Slows digestion and absorption of carbohydrates
- Helps control blood sugars
- Can reduce blood cholesterol
Which foods is soluble fibre found in?
- oats, nuts, legumes
- Fruit e.g prunes, bananas, apples
- vegetables e.g potatoes, broccoli, carrots
What are some downsides of insoluble fibres?
- Cannot be broken down by the body
- Adsorbs water
- Swells = bulkier stools
What foods can insoluble fibres be found in?
- Wholegrain foods e.g brown rice, brown bread
- Fruit and vegetables peel/skins e.g sweetcorn
- Nuts and seeds
Why is excess of fibre bad?
Too many cereals = limit absorption of iron and calcium
What are some deficiencies from fibre?
- Constipation
2. Could increase risk of bowel cancer
What is the reference intake for fibre?
- Adult = 30g per day
- children = less due to size per day
Where is dietary fibre especially found?
In the skins/ peels of fruit and vegetables
