DK Science: Health
Many factors play a part in keeping your body and mind in good health. These include taking plenty of EXERCISE, eating a healthy DIET, and observing some basic rules of HYGIENE. Other aspects include getting enough sleep and having the health check-ups and disease prevention measures (such as vaccination) that are advised for each age group. By avoiding harmful habits such as smoking, people can also reduce their risk of many diseases.
Table 24. SOME THREATS TO HEALTH
| ACTIVITY | DANGER |
|---|---|
| Smoking | Tobacco smoking is very harmful to health. It causes many types of cancer, damages lungs, contributes to heart disease, and reduces life expectancy. Tobacco contains a substance, nicotine, that is highly addictive. |
| Alcohol use | Excessive use of alcohol can seriously damage some body organs and increases the risk of cancer. It can lead to addiction (difficulty abstaining) and mental problems. Limited alcohol use (up to a certain number of units per week as advised by a doctor) can, however, be good for an adult’s health. |
| Drug use | Using drugs not prescribed or recommended by a doctor can cause some serious mental and physical health problems, depending on the drug. Addiction is common. |
Exercising regularly to keep physically fit is a vital part of a healthy lifestyle. Even moderate exercise performed regularly helps protect against disease and prolongs life expectancy. As well as being enjoyable and improving strength and suppleness, regular exercise improves the efficiency of the muscles, the heart, and the whole circulatory system. It also helps prevent a person from becoming overweight, which has many negative effects on health.
There are two main aspects to hygiene. One is to observe some basic measures for minimizing the spread of germs. This includes washing hands before handling food and after going to the toilet or playing with a pet. The other aspect is simply a matter of keeping clean and odour-free. Taking a bath or shower regularly, and washing the body thoroughly all over using plenty of soap and water, is highly effective.
Maintaining your teeth and gums in good condition is important to overall health as well as for avoiding tooth decay and gum disease. Daily flossing, as well as brushing twice a day, can achieve this.
Swimming, cycling, jogging, and brisk walking are valuable forms of what is called aerobic exercise. This describes any activity that can be done continuously for at least 12 minutes and uses oxygen to provide energy for your muscles. Most people should aim to do some vigorous aerobic exercise at least three times a week, for at least 20 minutes each session, to stay fit and in good mental and physical shape.
A healthy diet provides all the nutrients you need to grow and function normally. These include proteins, which supply materials for growth and repair; carbohydrates and some fat, which give energy; and tiny amounts of various vitamins and minerals, which play many roles in the body. Your diet should also provide fibre (indigestible plant matter). Eating a wide mix of foods should automatically supply all the nutrients you need. For really good health, however, you should limit your intake of sugar-rich and fatty foods.
One route to a healthy diet is to use a food pyramid. The bulk of a person’s diet should consist of foods near the base of the pyramid: carbohydrate-rich foods, vegetables, and fruit. These supply energy, fibre, vitamins, and minerals. Protein-rich foods, in the middle row, should be eaten in moderate amounts. Foods at the top of the pyramid, which supply energy but are low in most nutrients, are best eaten only in small amounts.
Healthy food is one that contains a mix of fresh ingredients, such as the components of this vegetable stir-fry. For a balanced meal, these might be combined with a carbohydrate-rich food, like rice, and a source of protein, such as some fried chicken. One advantage of including plenty of vegetables in the diet is that they are a good source of dietary fibre. This adds bulk to food and helps the functioning of the intestines.
