Nutrition Flashcards
What are the seven classes of food?
-Carbohydrates -Fats -Proteins -Fibre -Vitamins -Minerals -Water
What is the definition of a balanced diet?
A balanced diet contains adequate amounts of all seven groups.
Carbohydrates -What are all carbohydrates made up of?
-Chains of glucose molecules
Carbohydrates -When the chains are short…
When the chains are short, the carbohydrates are sugary to taste, e.g. the carbohydrates found in fruit, table sugar and chocolate. Simple sugars
Carbohydrates -When the chains are long…
Long chains of glucose molecules make up the starchy, more complex carbohydrates, e.g. in pasta, rice, bread and potatoes Complex sugars
Carbohydrates -How are they stored? -What happens when they are needed?
Carbohydrates are stored in the liver as glycogen and when they are needed they are broken down into glucose to be used in respiration.
Carbohydrates -What is there role?
The primary role of carbohydrates is for energy (particularly high intensity work). They are also essential for the nervous system to work properly
Carbohydrates -What is glycaemic index?
The number of glucose molecules in the carbohydrate not only determine what it is, but how hard it is to digest and how quickly it can release its energy. The Glycaemic index (GI) of food refers to how quickly it breaks down to release its energy.
Carbohydrates -How do sugary carbohydrates break down?
-Sugary carbohydrates break down much faster than starchy carbs as they are smaller molecules, and are said to be low GI.
Carbohydrates -How do complex carbohydrates break down?
Complex carbohydrates are high GI as they are made up of longer chains and so take longer to break down.
Fats
-How are they structured
Fats are made up of three fatty acid molecules attached to one glycerol molecule…
During digestion the triglyceride is broken up into a glycerol and three fatty acids. When they are broken down they are used for energy.
Fats
-As fats are bigger molecules than carbohydrates they…
- need more oxygen to break them down and so
- can only be used for low intensity exercise.
- However, this also makes them very energy rich and they contain more than double the energy contained in carbohydrates.
Fats
What are the states of fats at room temperature?
Where are they derived from?
Fats can be saturated and unsaturated.
Saturated fats tend to be solid at room temperature and are found in animal products
Unsaturated fats tend to be liquid at room temperature and are derived from vegetable products (often called “oils”)
Fats
What are unsaturated and saturated fats important for?
Unsaturated fats are important for the transport of fat soluble vitamins and saturated fats are important for insulation.
Fats
Explain the health risks associated with a diet high in saturated fat
- Heart attacks
- Atherosclerosis
- Stroke
- Diabetes
- Cancer
- High blood pressure
Fats
Cholestrol levels in terms of fats
It also leads to high cholesterol levels.
Cholesterol is made predominantly in the liver and is carried by the blood as
low density lipoprotein (LDL) and high-density lipoprotein (HDL).
Too much LDL can lead to fatty deposits developing in the arteries which can have a negative effect on blood flow. However, HDL takes cholesterol away from parts of the body where it has accumulated to the liver where it is disposed of.
Proteins
-What are proteins made up of?
Chains of amino acid
Proteins
-What do they provide?
- The ‘building blocks’ for tissue (muscle, ligaments, tendons)
- Growth and repair
- Produce enzymes, hormones & haemoglobin
Proteins
What can they sometimes be used for?
Although they are not usually used for energy, they can be used when carbohydrate and fat stores are exhausted, e.g. in cases of starvation or extreme exercise such as ultra-marathons or iron man competitions.
Proteins
A few facts about the consumption of proteins
When we consume food containing protein, the large protein molecule has to be broken down into the smallest units, amino acids, before it can be absorbed and used.
What the body builds from the amino acids depends on the body’s needs at the time. If you have been training and muscle fibres have been damaged, the amino acids will be rebuilt into muscle tissue (hypertrophy).
Fibre
What food is fibre found in?
Whole meat, oats and in fruit and vegetables
Fibre
Facts about fibre?
- It is the indigestible carbohydrate part of plants
- Provides no energy as we cannot break it down
- Adds bulk to faeces
- Reduces chance of constipation & bowel disease
- Binds to fats and cholesterol
Vitamins
Vitamins are chemical compounds required in only very small amounts. They play a vital role in energy production and metabolism
Generally, all the vitamins we require we can obtain through a well-balanced diet.
These are found largely in fresh fruit and vegetables.
Important vitamins
Vitamin B-12 –Makes RBC and keeps the nervous system healthy
B-complex–Release energy from food, healthy nervous system, eyes and skin heathy
Vitamin C–making blood vessels, skin & cartilage
Vitamin D–bone strength
