Transcript Fit and healthy There are 7 different types of nutrients which are

There are 7 different types of nutrients which are: carbohydrate,
protein, fat, minerals, vitamins, fiber, and water. some nutrients are
particularly rich in certain food for example, carbohydrate is used for
energy and is meanly rich in: cereal, bread, pasta, rice and potatoes.
Protein which is used for growth and repair is rich in: fish, meat,
eggs, beans, pulses, and dairy products. Fat which is used for
energy and storing in energy in the body to insulate it against the
cold is rich in butter and oil . Minerals which are used in small
amounts to maintain health is rich in: salt, milk, and liver. Vitamins
which are also used for health is rich in: dari food, fruit and
vegetables. Fiber which is good for keeping food going down the
guts and is rich in fruit and vegetables. Water is used for the cells
and body fluids and is rich in water.
It is important that you get the right amount of nutrient in
your diet, if you have too little of a particular food its said
you have a deficiency in that nutrient. For example if you
have deficiency in fiber you could get constipation. If you
have deficiency in iron you could have few red blood
cells. People with iodine deficiency may get a swelling in
their neck called a goiter.
Although we need small amounts of different vitamins, we
become ill if we don't get enough of each vitamin. For
example deficiency in vitamin A can cause blindness,
deficiency in vitamin C could cause scurvy which makes
gums bleed, and less vitamin D could cause rickets
which makes the legs bow outwards in growing children.
Food is a store of chemical energy. If you look on the side of food
packets you will see the food's energy content. This is usually
measured in kilojoules, kJ. If we eat too little food, we will use up our
store of fat and become too thin. If we eat too much food, especially
foods rich in sugar and fat, we will increase our store of fat and
become too fat.
It is important to balance the amount of food we eat with who we are
and what we do. The amount of energy we need from our food
depends on our age, our height and how much exercise we get.
For example, a one-year old baby needs 3850 kJ each day to continue
to grow, whereas an adult Olympic swimmer in training needs
15,600 kJ each day. Someone who sits at a desk all day will need
less food than their twin who climbs ladders all day to wash
windows.
The food we eat has to be broken down into other substance that our
bodies can use. This is called digestion, without digestion we could
not absorb food into our bodies to use it. Digestion happens in the
digestion system, which begins in the mouth and ends in the anus.
After we swallow, our food passes through these organs in
turn:esophagus or gullet, stomach, small intestine and the large
intestine.
Stages of digestion - food is digested in the mouth, stomach, and small
intestines. Then digested food is absorbs into the blood stream in
the small intestine. After that excess water is absorbed back into the
body in the large intestine. undigested food passes out of the anus
as faeces (pronounced "fee-seez") when we go to the toilet.
The liver and the pancreas play important part in digestion. The liver
produces bile, which helps the digestion of fat. The pancreas
produces chemicals called digestive enzymes.
The digestive system starts in the mouth with our teeth breaking the food into
small pieces, however these pieces are still to large to be absorbed by the
body. Food has to be broken down chemically into really small particles
before it can be absorbed. Enzymes are needed so that this break-down
happens quickly enough to be useful. Different types of enzymes are used
to break down different types of nutrieents. For example Carbohydrates are
digested in the mouth, stomach and small intestine. Carbohydrase enzymes
break down starch into sugars.
Proteins are digested in the stomach abd small intestine Protease enzymes
break down proteins into amino acids. Digestion of proteins in the stomach
is helped by stomach acid, which is strong hydrochloric acid. This also kills
harmful micro-organisms that may be in the food.
Lipase enzymes break down fat into fatty acids and glycerol. Digestion of fat in
the small intestine is helped by bile, made in the liver. Bile breaks the fat
into small droplets that are easier for the lipase enzymes to work on.
Minerals, vitamins and water are already small enough to be absorbed by the
body without being broken down, so they are not digested.Digestive
enzymes cannot break down fibre, which is why it cannot be absorbed by
the body.
The process of digestive system is: ingestion (eating) → digestion (breaking
down) → absorption → egestion
Abroption - digested molecules are absorbed in the small intestins and then
enter our blood stream. After that they are carried around the body, where
ever needed, br the blood stream. The inside wall of the small intestine
needs to be thin, with a really big surface area. This allows absorption to
happen quickly and efficiently. If the small intestine had a thick wall and a
small surface area, a lot of digested food might pass out of the body before
it had a chance to be absorbed.
To get a big surface area, the inside wall of the small intestine is lined with tiny
villi (one of them is called a villus). These stick out and give a big surface
area. They also contain blood capillaries to carry away the absorbed food
molecules.
Egestion - Excess water is absorbed back into the body in the large intestine.
What is left then is undigested food. This is stored in the rectum, the lower
part of the large intestine, until we are ready to go to the toilet. It then comes
out of the rectum through the anus as faeces. This process is called
egestion.
Smoking is very harmful to health. It causes around 80 per cent of deaths from lung
cancer, bronchitis and emphysema in the UK, and almost a fifth of UK deaths from
heart disease.
Tobacco smoke contains many harmful substances. These include:
tar
nicotine
carbon monoxide
Tar causes cancer of mouth, lungs and throat. It coats the surface of the breathing tubes
and the alveoli. This causes coughing and damages the alveoli, making it more
difficult for gas exchange to happen.
Smoke
Cells in the lining of the breathing tubes produce sticky mucus to trap dirt and microbes.
Cells with tiny hair-like parts, called cilia, normally move the mucus out of the lungs.
Hot smoke and tar from smoking damages the cilia. So smokers cough to move the
mucus and are more likely to get bronchitis.
Nicotine
Nicotine is addictive - it causes a smoker to want more cigarettes. Nicotine also increases
the heart rate and blood pressure, and makes blood vessels narrower than normal.
This can lead to heart disease.
Carbon monoxide
Carbon monoxide is a gas that takes the place of oxygen in red blood cells. This reduces
the amount of oxygen that the blood can carry. This means that the circulatory
system has to work harder, causing heart disease.
Drugs are substances that have effects on the body.
Medicines are drugs that help people suffering from pain or disease.
Recreational drugs are taken for pleasure.
Some recreational drugs are legal, such as tobacco, alcohol and caffeine. Most other
recreational drugs are illegal, such as cannabis, ecstasy and heroin.
Problems with drug use
Recreational drugs can be classified as depressants or stimulants. Most recreational drugs can
be addictive.
All drugs can damage the liver, because it is the liver that breaks drugs down in the body. Any
drug that is misused can cause damage to the body, as well as personal and social
problems. Injecting any drug with a needle and syringe that someone else has used may
lead to a number of diseases from infected blood, including HIV and hepatitis.
Depressants slow down messages in the brain and along the nerves. Alcohol is a depressant.
It is found in beer, wines and spirits such as vodka.
Other depressants include cannabis, heroin and solvents (eg glue and aerosols).
Here are some of the typical effects depressants have on the body:
feelings of well-being, slowed thinking, slowed muscular activity, a distorted view of the world,
or hallucinations
Some of the long-term effects of depressants on the body include damage to the liver, brain
and heart. They can also have the following effects:
alcohol can cause weight gain
solvent abuse causes a rash around the nose and mouth
cannabis causes loss of memory and concentration, as well as an increased risk of mental
illness.
Stimulants speed up messages in the brain and along the
nerves. This makes you feel more alert. Caffeine is a
stimulant and is found in cola drinks, coffee and tea. It
makes you feel more energetic and alert, but it can also
cause insomnia (difficulty in sleeping), headaches and
nervousness.
Cocaine, ecstasy and amphetamines are all illegal
stimulants. They make you feel more energetic and
confident, but they can damage the liver and heart. They
can also cause loss of memory and concentration, and
bring an increased risk of mental illness.