Diet and Energy
Carbohydrates are found in pasta, rice, potatoes and fruits and store slow release energy
Dairy is found in milk, cheese and cream and is used to strengthen bones, teeth and nails
Protein is found in meat and fish and is used to build and repair tissue
Fibre is found in bread and rice and is used to help waste leave your system
Fats are found in sweets and meat and are used as an energy store and for insulation
Vitamins (A and C) and Minerals are found in fruit and are used for eyesight(A) and skin, teeth and nails(C)
A healthy diet means the correct balance of food groups. An old person needs less energy than teenagers as teenagers are more active and they are still growing.
An athlete would require more energy than yourself as they are more active.
Energy from the diet comes from the carbohydrates and fats.
Some people are able to put on weight more easily than other as some people aren't as active and healthy as other. If you are less healthy you put on weight more easily. If you more healthy you put on less weight, not as easily to gain weight.
- Chemical reactions in the cells of the body take place in the cytoplasm
- Chemical reactions in the body are known as metabolism
- Metabolism can be faster or slower
- This 'speed' is called the metabolic rate
The metabolic rate varies from person to person. The comparison of muscle to fat in the body affects your metabolic rate. Men generally have a higher proportion of muscle to fat than women, so they have a lower metabolic rate. You can change the proportion of muscle to fat in your body by exercising and building up more muscle.
Exercise increases your metabolic rate for a time even after you stop exercising. Scientists think that your basic metabolic rate may be affected by genetic factors you inherit from your parents.
Malnourishment occurs: if you dont have a balanced diet then you will end up malnourished
Body Mass is lost when the energy content of the food taken in is less than the amount of energy expended by the body.
However, body mass is gained if the energy content of the food exceeds the amount of energy expended by the body. This can be associated with serious health problems.
Regular exercise improves your health.
Obesity in England is nearing epidemic proportions with one in five adults now dangerously overweight, costing the NHS £2.6bn a year. More than 31,000 people a year are dying prematurely (6% of all death) because of a lifestyle of foods high in fats and salt, over-reliance on cars and energy saving devices such as lifts and escalators.
- Obesity in England has tripled since 1980
- 1 in 5 adults are now obese; by 2010 it could be 1 in 4
- Two thirds of men and over half of the women are either obese or overweight
- Obesity costs the NHS at least £500m a year and the economy a further £2.1bn a year
BMI Index and Health Problems
Doctors do not just measure a person's weight; they study their body/mass index or BMI. This compares your weight to your height in a simple formula:
BMI= weight(kg)/height(m) then divide your answer by your height again
Most people have a BMI between 20-30 but below 18.5 or above 35 suggests you may have health problem.
Carry too weight is often inconvenient and uncomfortable. Obese people are more likely to suffer from:
- High Blood Pressure
- Heart Disease
Many people in developed world want to lose weight. You gain fat by taking in more energy than you need. There are several ways of losing weight:
- Reduce the amount of energy you take in by cutting back the amount of food you eat, especially energy-rich foods like biscuits, crisps and chips
- Increase the amount of energy you use by doing more exercise
- Do both! Reduce energy intake AND exercise more
Many people prefer to lose weight by eating 'slimming products' or undertaking a slimming programme. Some companies make millions selling food associated with their slimming programmes. Some are well thought-out, others do not work for most people and so slimming programmes need selecting with care.
The Atkins diet allows you to eat as much protein as you want but cut down on carbohydrates. It is thought that this increase the risk of heart disease.