Nutrition Assignment

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  1. Outline what is meant by a ‘balanced diet’ and explain why each component is required.

‘A balanced diet is important to maintain health and a sensible body weight. No single food will provide all the essential nutrients that the body needs to be healthy and function efficiently. The nutritional value of a person’s diet depends on the overall mixture, or balance, of food that is eaten over a period of time, as well as on the needs of the individual. A diet which includes a variety of different foods is most likely to provide all the essential nutrients.’ (

The balanced diet must contain the following elements in the correct proportions:

  1. Carbohydrates,
  2. Protein,
  3. Fats and oils,
  4. Vitamins: A, B1, B2 etc up to B12, C, D, E
  5. Mineral salts
  6. Fibre (Roughage)
  7. Water

Each of the above are need to make the body work and there is negative affect to our bodies if we do get the correct amount or do with out them altogether.  The following are the uses and what will happen if we do not the appropriate levels in our diet:

  1. : these provide a source of energy, if too much is consumed and you will gain excess weight and if too little is consumed you it will make you feel tired and lethargic.
  2. : these provide a source of materials for growth and repair too much protein in the diet and you will gain weight and might make a lot of urine, too little protein in the diet and you will not grow properly and wounds will not heal.
  3. : these provide a source of energy and contain fat soluble vitamins. Fat transports the fat-soluble vitamins A, D, E and K around the body, it has a key role in membrane structure, it cushions, and so protects, the internal organs, it is stored in adipose tissue (a thick layer of tissue under the skin) as a long-term fuel reserve. If you eat to much fat you will put on weight and the excess fat may also accumulate around your organs, especially in the abdominal cavity. To much fat in a diet will also cause heart disease.  If there is no fat in the diet at all the body will not get the fat soluble vitamins stated above.
  4. : these are required in very small quantities to keep you healthy they also assist enzyme activity and assist absorption.
  • Vitamin A (retinol): good for your eyes can cause night blindness if not enough taken in.
  • Vitamin B: about 12 different chemicals a lack of which can cause many diseases for example a lack of:  vitamin B1-thiamine will cause beri-beri nervous disorders, muscle weakness and heart failure.  Niacin a lack of which causes Pellagra where the skin becomes dark and scaly.  
  • Vitamin C: needed for your body to repair itself. Lack of Vitamin C will cause Scurvy which is bleeding under the skin and from the gums and wounds will not heal.
  • Vitamin D: can be made in your skin, needed for absorption of Calcium can also cause Rickets in children and soft bones and muscle weakness in adults.
  • Vitamin E:
  • Vitamin K: Lack of this vitamin will make the blood slow to clot.(Class Notes)
  1. : These are also needed in small quantities, but we need more of these than we need of vitamins.  We need these to:
  • Iron: required to make haemoglobin a lack of iron in the diet will cause anaemia.
  • Calcium: required for healthy teeth, bones and muscles.  Lack of calcium can cause bone weakness.
  • Sodium: all cells need this, especially nerve cells. If you have too much salt it can cause the following symptoms include: nausea, vomiting, diarrhoea and abdominal cramps. High concentrations of sodium in the body can also result from excessive water or fluid loss. Persistently high levels of sodium in the blood can result in swelling, high blood pressure, difficulty in breathing, and heart failure, and may be fatal.
  • Iodine: used to make a hormone called thyroxin a lack of this will cause Goitre (swollen thyroid gland).
  1. : this is required to help your intestines function correctly; it is not digested. Fibre helps in the digestive process and can help lower blood cholesterol.
  2. Water: Water makes up 50 to 70 per cent of an adult's total body weight and, without regular top-ups, our body's survival time is limited to a matter of days. Water's essential for the body's growth and maintenance, as it's involved in a number of processes. For example, it helps get rid of waste and regulates temperature, and it provides a medium for biological reactions to occur in the body. Water's lost from the body through urine and sweat, and must be replaced through the diet. If you don't consume enough you can become dehydrated, causing symptoms such as headaches, tiredness and loss of concentration. Chronic dehydration can contribute to a number of health problems such as constipation and kidney stones. (
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The key to a healthy balanced diet is not to ban or leave out any foods or food groups but to balance what you eat by consuming a variety of foods from each food group in the right proportions for good health.  As shown in the Table 1 below all the nutrients we need are found in lots of different foods.  


Table 1: Table of Nutrients and the food they are found in.

  1. Describe precisely what happens to a meal of fish and chips from being eaten (Ingested) to being used by the body ...

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