Lillian Liem 6S 26

Date:09-05-2004

Health

According to the World Health Organization (WHO), health is defined as a state of complete physical, social and mental well-being, and not merely the absence of disease or infirmity.

Factors affecting health

Diet

Nutrition is a cornerstone that affects and defines the health of all people, rich and poor. It paves the way for us to grow, develop, work, play, resist infection and aspire to realization of our fullest potential as individuals and societies. Conversely, malnutrition makes us all more vulnerable to disease and premature death.

In details, as heterotrophs we depend on the food we take in as the source of the chemical constituents required for the normal growth and functioning of the body. Deficiency in particular constituent such as mineral, vitamin, protein and so on will upset the normal functioning or growth of the body. Deficiency diseases of lacking calcium are rickets and bleeding. Lack of iron causes anaemia. Without enough vitamin A, C and D, leads to night-blindness, scurvy and rickets respectively. Protein is used as structural material and metabolic regulators. If our body does not intake enough protein, then they cannot build up body tissues for growth and repair of worn-out tissue efficiently. Furthermore, inadequate of it also cannot speed up all bio-chemical reactions in living organism in right rate and hormones cannot regulate physiological processes well.

A balanced diet contains all food substances in the right amount to keep amount to keep good health. It provides enough energy (from carbohydrates and fats) for activities, enough protein for growth and repair, enough vitamins, minerals, water and dietary fibres (roughage) for maintaining health. Carbohydrates, fats and proteins should be in the ratio of 5:1:1. Taking too much energy-rich food will result in problems like overweight or obesity (being very fat) because excess carbohydrates and fats taken in will be stored inside our body as fats. Moreover, poor diet is sometimes associated with a higher risk of certain non-infectious disease when studying the causes and prevention of high blood pressure, cardiovascular diseases. cancer and biabetes.

Exercise and rest

The amount of work the muscles can perform is limited by the amount of oxygen obtained during ventilation, and the efficiency of the cardiovascular system in supplying 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 on physical activities. As everybody knows, the skeletal muscles increase in size, strength and capacity for work with regular and moderate exercise. The muscles involves in ventilation become stronger and this the vital capacity of the individual is increased. Besides, the heart muscle increases in size in response to training. The heart stronger to increase the cardiac output. With a sufficient supply of oxygen, the high energy yield from aerobic respiration fuel the muscles to do work. Apart from taking exercise, having enough rest is also important for health. Muscular activity for a sustained period leads to accumulation of toxic wastes such as lactic acid and depletion of food reserve. With this knowledge, students can appreciate the importance of rest to health. It is because allowing exhausted cells to undergo a period of inactivity or low activity for removing toxic waste and replenishing the food reserve in the cells.

Alcohol abuse

Alcoholism is also known as "alcohol dependence." Alcoholism is now accepted as a disease. It is a chronic and often progressive disease. Like many diseases, it has symptoms that include a strong need to drink despite negative consequences, such as serious job or health problems. Like many diseases, it has a generally predictable course and is influenced by both genetic (inherited) and environmental factors.

Alcohol slows down the speed at which nerve impulses are transmitted. This lengthens the reaction time of the affected person making him slow to respond. The ability of an individual to reason, to make judgment, and to co-ordinate is reduced as alcohol depresses the activity of the parts of the cerebrum controlling these functions. Drinking alcohol over a long period of time leads many serious diseases such as malnutrition and liver failure. Since alcoholic beverages are high in caloric content but low in nutritive value, excessive intake they usually cause malnutrition. Also, alcohol is mainly metabolized in the liver. The mechanism by which the hardening develops is still unclear, but it appears to involve the consequences of the metabolism of excessive amounts of alcohol.

Smoking

Cigarette smoke contains tars, nicotine and about 400 harmful substances. These substances cause extra mucus secretion in the respiratory tract and the lungs. Nicotine is addictive, it causes the wish to smoke more and more cigarettes. These substances stop the movement of cilia, stopping them from moving the unwanted substances up the respiratory tract. The unwanted substances enter the lungs and reduce the area for gas exchange. The smoke also irritates the bronchi and causes them to contract. This reduces the amount of gas which can be exchanged due affect health. Smoking may cause many diseases such as lung cancer, chronic bronchitis, emphysema and coronary heart diseases.

Besides, the process of breathing in smoke from cigarettes being smoked by a nearby smoker is called passive smoking. Cigarette smoke coming out from a burning cigarette contains many harmful substances. Non-smokers who breathe in this smoke may suffer from irritations of the nose, throat and eyes. They can also suffer from smoking-related diseases. Smoking is very hazardous to health. To maintain a healthy body, we should avoid smoking or being near to people who are smoking.

Conclusion

Being a healthy person, we should have a balanced diet, regular exercise, enough rest, not to abuse alcohol and not to smoking. If we can do so, disease or infirmity can be kept away from us and our life can be longer.