Obesity Essay, Research Paper
WEIGHT CONTROL is the process of losing or avoiding excessive body fat. It is based on the relationship between the amount of food you eat and the amount of exercise you get. The less you eat and the more you exercise, the less fat you will have. Weight control has medical importance because being obese (too fat) can lead to health problems. Obesity is a serious disorder and may result in emotional and social problems. Overweight people may not be obese, though the word overweight is often used for obese. Being overweight means weighing more than the average for a certain height.
Some people weigh less than average for their height because they have small bones and muscles. Others are underweight because they have less fat. In either case, being underweight is not unhealthy. But people may be underweight as the result of a disease–cancer, diabetes, or tuberculosis, for example. In some children, underweight may be the first sign of growth failure. An underweight person should consult a doctor. If no illness is found, there is no reason to worry.
An overweight person who is not too fat does not need to lose weight for health reasons. The person would do better simply to stay physically fit with such exercise as walking or taking part in sports.
Dangers of Obesity
Obese people are more likely than thin people to get certain diseases. The treatment of these diseases among the obese is also less likely to succeed. Such diseases include appendicitis, cirrhosis, diabetes, and diseases of the heart and blood vessels, especially coronary heart disease. A fat patient with one of these diseases has a better chance of recovery if he or she reduces.
Obese people have more falls and other accidents than thin people because they are slower and clumsier. Their recovery from injury is often difficult because surgery performed on them is complicated. Obesity cuts down freedom of movement, especially in the elderly, and thus can lower general health because of lack of exercise. The decreased freedom of movement in obese patients with arthritis also makes treatment difficult.
In many parts of the world, obese people may be rejected in various ways. Fat people are often treated unkindly by others, including their classmates in school. They generally have less social success than other people and may find it harder to get jobs.
Causes of Obesity
Overeating. You can gain or lose weight as a result of eating more or fewer calories than you need. A calorie is a unit used to measure the heat energy that the body gets from a certain amount of food. If you eat more calories than you use, most will turn into body fat. If you eat fewer than you use, your body will convert its fat into energy. During any period of days or weeks, if you eat 3,500 more calories than you use, you will gain 1 pound (0.5 kilogram). You will lose a pound of body fat if you eat 3,500 fewer calories than you use. Some countries that use the metric system measure the heat energy obtained from food in joules instead of calories. About 4,182 joules equal one calorie.
A surplus of calories is necessary for growth in children and pregnant women. But they will gain excess body fat if they eat too many calories. See CALORIE.
The amount of food you eat can play a much more important role in weight control than the kinds of food. People who are overweight, of normal weight, or underweight may all eat the same kinds of food. Their weight difference results from the amount and type of food they eat in relation to the amount of energy they use.
Certain centers in the brain control appetite, hunger, and satiety, the group of sensations that cause you to stop eating when your appetite and hunger have been satisfied. These brain centers normally make people eat an amount of food that provides enough energy for their needs. The feeding centers cause people to want to eat. The satiety centers act as a brake on the feeding centers and make people want to stop eating.
The feeding and satiety centers are extremely complicated mechanisms. They may be disturbed by such causes as emotional pressures and physical characteristics. For example, emotional pressures such as great disappointment cause some people to stop all physical activity. At such times, these people eat more than they usually do–and gain weight. Other people move around more and eat much less–and lose weight.
Some scientists believe that overfeeding infants causes them to develop too many fat cells. They claim that these cells store fat so readily that such people are likely to be obese for the rest of their lives.
Physical Inactivity is a leading cause of obesity among all age groups, but especially among children and teen-agers. Most obese young people do not eat more than young people of normal weight. But they are so inactive that, even with a moderate appetite, they eat more than they need–and accumulate excess fat.
Exercise uses up many calories, and the more vigorous the activity, the more calories are used. A 150-pound (68-kilogram) person walking at an average speed of 3 1/2 miles (5.6 kilometers) per hour will use up 502 calories–the number of calories in a malted milk shake–in 97 minutes. That person will use up the same number of calories in 61 minutes by riding a bicycle, or in 26 minutes by running.
The number of calories used is proportional to a person’s weight. If you weigh 75 pounds, for example, you will use up half as many calories as a 150-pound person by doing the same exercise for the same length of time.
The appetite of active people can increase if they become very active. If they become inactive, their appetite will not necessarily decrease. Appetite does not go below a minimum level even if activity drops.
Heredity. Scientists have learned much about the relationship between heredity and obesity in animals, especially mice. This relationship is based on genes, the basic units in cells that determine inherited characteristics. Genes determine whether excess weight is stored as lean or fat tissue. Scientists have discovered that mice and certain other animals have a gene that causes the satiety center not to operate. Other genes in some mice cause their bodies to overproduce certain hormones. As a result of these hormones, the mice make body fat too easily or use it up with difficulty. Still other genes cause some mice to become obese more quickly than others when physically inactive or when given a diet high in fat. See GENE; HORMONE.
In human beings, the action of genes is not as well known as in animals. However, there is evidence that some people are more likely to become obese than others because of their genes. For example, studies of high school students show that only about 8 per cent of the children of thin parents were obese. Among families where one parent was obese, 70 per cent of the children were fat. Among families with both parents obese, 80 per cent of the children were fat. Adopted children do not show this relationship to their adoptive parents.
Diseases and Other Causes. Obesity may result from a number of diseases. Some ailments of the endocrine glands cause these glands to release too much of a hormone into the blood stream. The excess hormone disturbs the feeding and satiety centers of the brain. In addition, obesity can result from damage to these brain centers caused by infection, injury, or a tumor.
How to Control Obesity
You should consult a physician and have a medical checkup before starting an extensive weight reduction program. The advice of a dietitian is also useful. An obese person may need psychological help as well, especially if the person is young and has been teased and made to feel guilty, hopeless, or worthless. Psychological treatment can help remove these feelings so that the obesity can be treated as a medical problem.
Diet. The first step to weight reduction is to develop a healthy diet that stops weight gain. Any reducing diet must provide fewer calories. If a man needs 3,000 calories a day to maintain his weight with his habits of life, he should eat only 2,000 calories a day to lose 2 pounds (0.9 kilogram) a week. It is generally dangerous to lose weight any faster.
The foods in a reducing diet must be well-balanced. That is, they must provide enough of all the nutrients needed for good health. There is no evidence that extreme diets–for example, “low carbohydrate” or “low protein” diets, or diets based on single foods–have any advantage over a well-balanced diet. For information on well-balanced diets, see NUTRITION. A reducing diet should also be good tasting and easy to buy and to cook.
A weight reducer should study charts that give the number of calories in various foods. Many people believe that such foods as baked potatoes and bread have many more calories than they do. They also underestimate the calories in such foods as steak.
The distribution of calories among meals and snacks is up to the individual. Some people do not get too hungry if they divide their calories among four or five light meals or snacks a day. Other people are able to follow a diet better if they eat three meals a day and have no snacks.
Exercise. A person going on a reducing diet must get more exercise. But an obese person–even one who is otherwise healthy–should not suddenly start a program of prolonged, heavy exercise. The strain on the heart would be dangerous. An exercise program should be developed gradually. One good way to start is to take daily walks, increasing their duration. More demanding exercises can be added as the person becomes thinner and fitter. A person should build up to five to six hours of exercise per week. A physician should be consulted before starting any vigorous exercise program.
Surgery. Extremely fat people whose obesity is life-threatening and who fail at dieting may have to undergo a surgical operation to reduce the size of the stomach. In one such operation, called gastroplasty or gastric stapling procedure, the surgeon uses a large stapling device to close off most of the patient’s stomach. After the surgery, the patient can eat only a small amount of food before becoming full.
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