Carbohydrates Flashcards
Name the two functions of carbohydrates
Provides energy
Acts as a protein sparer - protein can be used for its main functions instead of as a secondary energy source
Name the three types of carbohydrates. Which are complex and which are simple?
Sugars - simple
Starch - complex
Dietary fibre - complex
What is the scientific name for starch?
Polysaccaride
What is starch made up of?
Chains of sugars
What are the three most important starches?
Starch, Pectin, Glycogen
What is ‘starch’? What is is made from? How big is it?
The main food store in plants. Many glucose molecules. The size of molecules vary with each plant.
What is pectin? What is its main use in food? What is its main use in the body?
Found naturally in some fruits. It forms a gel in water and helps jams to set. It is thought to reduce cholesterol in the blood.
What is glycogen? What is its main use in the body?
Made from glucose by humans. Small amounts are stored in liver and muscles as an energy reserve.
What are good sources of starch?
Root vegetables, cereal and cereal products
Name some symptoms of deficiency from starch. Are they common?
Lack of energy - drop of level of glucose in blood
Weight loss - body will start to use fat stores if continued
Severe weakness - if fat stores are depleted, protein stores are used.
These are all unusual
How much of the energy in your diet should come from carbohydrates?
50%
What happens if there is an excess of starch? What can it lead to?
If not used, it is converted to fat and stored in the body. It can lead to obesity. Obesity can lead to further health issues: increased risk of type 2 diabetes an cardiovascular diseases
Wha could high levels of sugar lead to?
Tooth decay and obesity
Does sugar contain any other nutrients?
No
What do artificial sweeteners do?
They sweeten food/drink without increasing the energy content
What are hidden sugars and what can we do to prevent shoppers being caught out?
They are sugars hidden in foods you wouldn’t expect sugar to be in. Shoppers should check food labels carefully.
Give examples of what you could look for on a food label to catch hidden sugars. What could sources of hidden sugars include?
Corn sugar, dextrose, molasses, invert sugars, words ending in -ose are sugars.
Tomato ketchup, ready meals, ready-made sources.
Complete the sentence : ‘sugars can be named based on…
…where they are found’
Define fruit sugars
Sugars that occur naturally and are found within the cell walls.
What is a free sugar?
A sugar which has. Been released from the cell wall or is added to the food.
Which one is better for you: free sugars or fruit sugars?
Fruit sugars
Why are sugars also known as quick release energy?
They are simple and easy to break down so therefore they are quick to absorb
Name the two ‘catagories’ that sugars are divided into and give some examples
Monosaccharides (simple) and Disaccharides (double)
Monosaccharides - Glucose (fruit + veg), fructose (fruit + honey)
Disaccharides - Sucrose (sugar + syrup), Lactose (dairy), Maltose (cereal)
How might you identify sugar on a packet?
Usually: -ose means it is a sugar
-ate means it it the enzyme that breaks down the corresponding sugar.
E.g. lactose and lactase
What type of carbohydrate is dietary fibre?
Polysaccharide (Non-Starch polysaccharide)
Give some sources of dietary fibre
Whole grain cereals and products, fruit and veg, pulses
Name the four functions of dietary fibre
Maintaining a healthy digestive system
Weight control
Prevents bowel disease: constipation, diverticulitis, bowel cancer
Providing soluble fibre for lower cholesterol
Name the two types of fibre
Soluble and insoluble
What are the functions of soluble fibre?
Slows digestion and absorption of carbohydrates
Helps control blood sugars
Can reduce blood cholesterol
Give some sources of soluble fibre
Oats, nuts, legumes, fruit (e.g. prunes, bananas, apples), vegetables (e.g. potatoes, broccoli, carrots)
Name the functions of insoluble fibre
Cannot be broken down by the body
Absorbs water
Swells (leading to bulkier stools)
Give some sources of insoluble fibre
Whole grain foods, brown rice, fruit and vegetable peels/skins, nuts and seeds
What happens if there is an excess of dietary fibre? What if there is a deficiency?
Too many cereals limits the absorbtion of iron and calcium
Constipation, digestive problems and an increased risk of bowel cancer
What is the Daily Reference Value for dietary fibre?
Adults = 30g Children = slightly less due to size
