Health and Disease

Health and Disease

Good health habits include a balanced diet, adequate amounts of sleep and exercise, cleanliness, and a positive mental attitude. Maintaining these habits can help people avoid many health problems. However, very few people go through life without getting some type of disease. Many of these diseases, such as measles, mumps, polio, and the flu, are easily avoided by having proper vaccinations.


Diseases have many causes. Germs such as bacteria and viruses can enter the body and multiply, causing infectious diseases. Some infectious diseases are acquired (delivered or obtained) or transferred from one person to another. These are called communicable diseases. Other diseases, such as arthritis, are caused by body parts wearing out with age. Many diseases are triggered by lifestyle choices. Eating a diet of fatty foods can lead to heart disease. Smoking or chewing tobacco products can cause lung and heart disease.

Some infectious diseases can be acquired only once. The reason is that the body develops an immunity, an ability to resist the disease, that protects it from further infection. An adult who had measles as a child will not acquire it again. Hygiene habits such as regularly washing hands help people avoid many germs.


Sexually transmitted diseases (STDs) are caused by germs that travel through sexual contact. The chart on the next page shows symptoms, diagnosis, and treatment of the most common STDs. All STDs can be prevented by avoiding exposure to them.

Sexually Transmitted Diseases

Disease Symptoms Treatment
Chlamydia Pain; itching; discharge; inflammation; scarring; infertility Antibiotics
Gonorrhea Discharge; itching; pain; swelling; abnormal bleeding Antibiotics
Syphilis Organ damage; mental problems; blindness; deafness; heart failure; death Antibiotics
Herpes Sores that ooze and scab; fever; swollen glands; body aches to treat symptoms No cure; antiviral medications makes people susceptible to infectious diseases and cancers
AIDS Flu symptoms; swollen glands; skin rash; No cure; anti-retroviral drugs slow virus growth and organ damage

Cardiovascular Disease

Cardiovascular diseases affect the heart and the blood vessels. A common cause of this disease is the buildup of fatty deposits inside blood vessels. These deposits can make the arteries stiffer and more resistant to blood flow. This forces the heart to pump harder, raising the blood pressure.

High blood pressure can lead to a sudden failure of the heart, called a heart attack. A sudden failure of the blood supply in the brain causes an event called a stroke. Smoking, obesity, stress, lack of exercise, and a high-fat diet can increase the risk of cardiovascular disease. A high-salt diet can make high blood pressure worse.


Cancer is the uncontrolled growth and spread of abnormal cells in the body. Cancer may appear in the breasts, lungs, brain, bones, skin, or other organs. The seven warning signs of cancer, shown in the chart below, have saved many lives. Some doctors add rapid weight loss and extreme fatigue to those warning signs.

Early Warning Signs of Cancer
Unusual bleeding or discharge
A lump or thickening in the breast or elsewhere
A sore that does not heal
A change in bowel or bladder habits
Hoarseness or cough that continues
Indigestion or difficulty in swallowing
A change in size or color of wart or mole

Researchers are learning more and more about cancer. Many cancers can now be treated successfully if they are found and treated in the early stages. Surgery to remove tumors is now routine. Radiation and a variety of chemicals are used to destroy cancerous cells that cannot be removed surgically.


Diabetes is a disease in which the body does not produce enough of a hormone called insulin. Insulin helps the body use and store the sugar glucose. Symptoms of diabetes include frequent urination, extreme thirst, and fatigue. Uncontrolled diabetes can lead to blindness, diseased legs and arms, and ultimately, death.

Many people inherit a tendency to develop diabetes. Being overweight and not getting enough exercise greatly increase the risk of diabetes. The disease can be controlled through diet and exercise, as well as insulin treatments.


In cirrhosis, the cells of the liver are replaced by scar tissue. The scar tissue prevents the liver from functioning properly. People with the disease may bruise easily, have nosebleeds, and vomit blood.

Alcoholism and poor nutrition are the major risk factors for cirrhosis. Correcting the diet and avoiding alcohol can stop the disease, but the liver cannot be repaired. Without treatment, cirrhosis leads to death.


As people age, many get arthritis. They have some pain or difficulty with their joints. When the joints become swollen and stiff, the pain can be quite severe. Bony deposits may develop over the joints, locking them in place. Knees, hips, fingers, and toes are common sites for arthritis.

Heredity and obesity contribute to the disease. Although there is no cure for arthritis, the pain can be reduced with medicine, special exercises, and the application of heat.

Nutrition and Diet

The body needs nutrients to carry out the functions of maintenance, growth, repair, and reproduction. As a result, a well-balanced diet is essential. Nutritionists study foods that the body needs to stay healthy. Six types of nutrients are vital to life. They are carbohydrates, fats, proteins, vitamins, minerals, and water.

Good nutrition means eating the right foods in the proper proportions. A meal should include a range of different foods that provide a balance of carbohydrates, proteins, vitamins, and minerals. Every packaged food sold in the United States is required by the Food and Drug Administration to bear a nutrition facts label that lists the percentage of nutrients contained in it. Some states require that restaurant chains provide nutritional information on all menu items to consumers.

Vital Nutrients

Carbohydrates are the starches and sugars that are the main energy source for the body. They are supplied in large amounts in grains, fruits, and vegetables.

Like carbohydrates, fats provide a concentrated dose of energy. Large amounts of fats are present in oils, dairy products, nuts, and meats. The body needs only very small amounts of fat.

In the body, proteins are broken apart into amino acids. The body can manufacture most of the amino acids it needs to make new cells and to repair old cells. Nine of these acids, however, cannot be made and must be supplied in our food every day. To work, these essential amino acids must be present in the body at the same time.

Proteins from animal sources, such as fish, eggs, cheese, and meat contain all of the essential amino acids. Combinations of certain vegetables, such as corn and beans, can combine to provide the essential amino acids. Vegetarians must learn to plan their meals carefully to make sure that all the essential amino acids are available to the body at the same time.

Vitamins and minerals in small amounts are needed to regulate the body’s activities. Each has a specific function. Some break down fats into proteins; some build bones. Others allow nerves to carry messages or muscles to contract.

Water is the body’s most important nutrient. It is used for almost every bodily function. Without water, people can survive for only a few days.


Calories are a measure of energy value. Everyone needs calories for energy. Not everyone, however, needs the same number of calories. People who are very active need more calories than those who get little exercise. Younger people generally need more calories than older people do.

Nutritionists know that some foods are more valuable than others. Milk, for example, provides just a bit of almost everything the body needs. A candy bar, on the other hand, provides many calories with few nutrients. Nutritionists call these “empty” calories. They may provide quick energy, but they are of no lasting benefit to the body.

A Balanced Diet

No single food provides all the nutrients that the body needs to stay healthy. This is why it is important to eat a balanced diet, which is made of a variety of healthful foods.

The new food guide shows what a healthy and balanced diet might look like. It includes the five groups of food that include essential nutrients that promote good health. These are: fruits and vegetables, grains, proteins, dairy, and oils. Oils are not a food group, but used sparingly, they are important nutrients. As a general rule, you should make half your plate fruits and vegetables. You should select whole grains, such as wheat flour, oatmeal, and brown rice, at least half the time. Following these guidelines provides an excellent foundation for a diet that promotes wellness.