Obesity has become one of the commonest nutritional disorders in the world. Modern industry made high-energy food more available and more tempting. At the same time, we spend more time in sedentary work or in front of television and computers. We become obese when our weight exceeds 120% of our expected ideal body weight. Obesity is more common in lower social classes with less chance of exercise and more intake of high-calorie low-priced food. In people past their middle age, there is a build-up of more weight due to slowing of metabolism, although they maintain a reasonable healthy food intake and average activity. More than half of the middle-aged people are obese. Women are more likely to gain weight due to hormonal changes, in particular during pregnancy and after the menopause.
To think that obesity is simply a result of higher food intake in excess of energy requirements of the person is over-simplification. Some people are physically active although their weight increases in spite of normal food intake. Others may lose weight while eating normally and their activity is within normal. Some metabolic disorders lead to increase in body weight as in the case of under-active thyroid gland. Abnormal eating habits in childhood shape body weight in later life, which is possibly due to increase in the number of fat cells in the body during the growing up period.
Obese people are likely to have poor judgment of how much they eat. In some obese people, external stimuli such as smell and sight of food prompt eating rather than internal stimuli such as hunger feeling or gastric motility. Some people eat more in response to stressful emotional states as form of comfort eating. The symbolic meaning of food as a sign of love and care influence our eating impulses, it may remind us of times when parents gave food and sweets while we were in distress as children.
There are certain medical conditions that may lead to obesity. Obesity run in families and genetic factors play an important part in making some people obese.
The usual approach to handle obesity is calorie reduction. A careful programmed diet control with total calories not exceeding 1000 calories per day would achieve a weight loss of 1-2 kilograms every week. Dieting may result in irritability and a sense of depression and sadness in some people and this may be the actual cause of relapse in many cases.
Group psychotherapy or support groups are helpful and effective. The Therapist may need to check the person's life style and circumstances. Problems such as marital conflict or other cause of distress may lead to overeating and excessive weight gain.
Behaviour therapy is a useful method to deal with obesity problems. One of its techniques is self-monitoring, self-regulation and self control. One of these techniques is keeping a diary of food intake and calorie content of each item. It is also imperative to control the environmental cues that lead to excessive eating. Altering the eating habits and eating triggers may help in changing the faulty eating pattern. Groups, for example those run by Weight Watchers, help to reinforce weight control through self-reinforcement and group reinforcement. Obese people have to manage the usual feeling of guilt and sense of failure as these feelings may lead to relapses.
Drugs have a role in treatment of obesity although they may cause a good number of side effects. Some of these appetite suppressants are stimulants derived from amphetamines, and it is advisable to use them for short period. They are less practical for extremely obese patients. Orlistat (Xenical) is a drug that reduces absorption of fat in the intestine. Sibutramine (Reductil or Meridia) is an anorectic or appetite suppressant, which reduces the desire to eat. Sibutramine has been withdrawn from the market in many countries due to the risks of stroke and myocardial infarction. Metformin (Glucophage) can reduce weight in people with Diabetes mellitus type 2. Exenatide (Byetta) is a long-acting analogue of the hormone GLP-1. GLP-1 delays gastric emptying and promotes a feeling of satiety. Byetta is currently available as a treatment for Diabetes mellitus type 2. The person has to inject it under the skin twice daily which make it unfeasible, and it causes severe nausea in some patients, especially during the first few days of therapy.
Different kinds of surgical procedures are valuable in weight reduction for obese patients. These procedures result in weight loss through one of two ways: mechanically restricting the size of the stomach or bypassing a portion of the intestines; however, several procedures exert their effects by both mechanisms. Restricting the size of the stomach limits the quantity of food a patient can eat at a single meal. Bypass procedures decrease the proportion of nutrients that are absorbed from a meal. Gastric banding and Vertical Banded Gastroplasty achieve weight loss by creating gastric restriction. Intestinal bypass is a procedure, which connect the proximal part of the small intestine to a segment of distal small intestine, in this way it bypass the majority of the absorptive capacity of the small intestine.
Obesity is common problem in our modern life. Different factors contribute to obesity including the age, sex and social class. Our eating habits and activity add to weight gain. Obesity runs in families and there is a genetic vulnerability. Certain physical and psychological conditions lead to weight gain. Treatment is through dieting, medication, psychotherapy or surgical restriction of intake of food.