Catherine Poong King Sang 6S 29

HEALTH

There is no doubt that health is the most important thing in our lives.No matter you are poor or rich,you must need a health body to maintain a happy life.

However,everybody must have experienced illnesses.Scientists and doctors are still working very hard to investigate various types of medicine to fight for the health of human.Actually,we can do something to make the body immunity stronger enough to maintain health.

Diet is the most related factor of our health.It's because our health depends much on what kind of diet we have.A diet is the sort of food we eat and drink.Food is any substance which contains nutrients.It can provide us carbohydrates,proteins,

vitamins and minerals which are for energy,growth and repair.To maintain good health,we need a balanced diet.A balanced diet contains all of the following groups of food substances in the right amount for our age and gender.

Eating too little,too much or bias towards certain foods is also unhealthy.It may lead to various deficiency diseases.Some people believed that taking in a lot of vitamins will make them healthier.Actually,it is wrong.On the other hand,it may even be unhealthy.Our body cannot store excess water-soluble vitamins e.g. vitamin C.They are easily excreted.However,fat-soluble vitamins can accumulate in our body.They can be poisonous if large amounts are present.Taking in excess vitamin A or D over a long period may result in brittle bones.

Yet,lack the necessary vitamins in our diets,we may suffer from deficiency

diseases.For example,a lack of vitamin A,C or D will lead to night blindness,

scurvy and rickets respectively.

Eating too much will increase our body weight.When the body weight exceeds normal,we are said to be overweight.Obesity is a common nutritional disorder in wealthy countries.It may be caused by hormonal disorders,but the usual cause is the intake of an excess of energy-containing foods.Excessive intake of fat may result in high levels of blood lipids and cholesterol. It accelerates the development of atheroma and causes coronary artery disease.To be healthy and fit,we must eat just the right amount of food in order to get the right amount of energy. A healthy diet also encourages more vegetable, fruit and fiber intake, which helps to lower the blood cholesterol level.

Besides,we need to do regular exercises.The amount of work the muscles can perform is limited by the amount of oxygen obtained during ventilation,and the efficiency of the cardiovasculart system in supplying oxygen to the muscles.As the body is trained to be more efficient in obtaining oxygen and delivering it to the muscles,people who exercise regularly are able to accomplish regular activities easier and respond more readily to sudden demand to physicle activities.For example,the heart muscle increases in size in response to training.The heart can beat stronger to increase the cardiac output.

Continual activity for a sustained period leads to accumulation of toxic wastes and depletion of food reserve.Therefore,rest is very important for health.It allowing exhausted cells to undergo a period of inactivity or low activity for removing toxic wastes and replenishing the food reserve in the cells.

Many people like drinking alcohol especially youngsters.Howver,drinking alcohol have many disadvantages.First of all,alcohol slows down the speed at which nerve impulses are transmitted.This lengthens the reaction time of the affected person making a drunk person slow to respond.The ability of an individual to reason,to make judgement,and to coordinate is reduced as alcohol depresses the activity of the parts of the cerebrum controlling these functions.That's why a drunk driver who is driving is very dangerous.

Drinking large amounts of alcohol overa long period of time can cause health problems such as malnutrition and hardening of the liver.Malnutrition may result in long-lasting alcoholism because alcoholic beverages are high in caloric content but low in nutritive value.Hardening of the liver is associated with alcohol abuse.Alcohol is mainly metabolized in the liver.The mechanism by which the hardening developes is still unclear,but it appears to involve the consequences of the metabolism of excessive amounts of alcohol.

All in all,in order to maintain a healthy life,we must have a balance diet,enough rest and regular exercise.Don't drink large amount of alcohol as well.I am sure that we can stay healthwise in our lives.