How To Manage Obesity??

What is Obesity?

          Obesity is a chronic metabolic disorder leading to the excess storage of the fat in the body. It results from chronic net increase in the energy intake than expenditure i.e. there is more ingestion of the food than is necessary for the body of its victim. Besides causing increased morbidity and mortality from related health problems such as cardiovascular disorders, type II diabetes, osteoarthritis, sleep apnoea, etc., it also causes various psychosocial problems in obese persons such as poor self-esteem, depression, mearge employment prospects etc.

          The body fat can be measured by using various 'surrogate markers' such as Body mass index(BMI) and waist circumference. The body mass unit(BMI) is defined as body weight in(Kg) divided by height squared(m²) and is used to distinguish under weight (<18), healthy weight (18.5-25.0), overweight (25.1-29.9) and obese (>30). However, the body mass index provides incorrect information of body fat in highly muscular individuals.

Classification of Overweight and Obesity in Adults

Classification    BMI(Kg/m²)   Risk of co-mor-
                                                     bidities
Underweight    <18.5               Low
Normal range   18.5-24.9        Average
Overweight       25.0-29.9        Mildly increas-
                                                     ed
Obese                 >30.0
Class I                 30.0-34.9        Moderate
Class II                35.0-39.9        Severe
Class III              >40.0               Very severe

               Increase in the waist circumference (>94cm in men and >80 cm in women) greatly increases the risk of central adiposity and morbidity from obesity related disorders.

Types of Obesity

             Obesity can be considered to be of two types: 

1) Hypertrophic

2) Hyperplastic

Hypertrophic Obesity

             In Hypertrophic obesity (also called adult onset obesity) people who were thin or of average weight and quite active when young become less active as they become older. They begin to gain weight at age of 20 to 40, and although they no longer use as many calories, they still take the same amount of food as when they were younger. The unused calories are turned into fat. In this type of Obesity, the amount of fat in each adipocyte (fat cells) increases, but the total number of adipocytes does not increase.

Hyperplastic obesity

In Hyperplastic obesity (occuring early in life) the total number of adipocytes increases. People with Hyperplastic obesity are obese as children and become more obese with age. This type of obesity is a major health problem in school-aged children.

Causes of Obesity

               The causes of obesity is multifactorial and complex. Numerous culprits can become the triggers. The first and foremost are the environmental factors such as the easy availability of palatable energy dense foods and increasingly sedentary life styles. The term 'toxic environment' has been coined to represent these life styles. Then the genetic factors also increase the predisposition of the individual to develop Obesity and the genetic inheritance of obesity varies from 30 to 70% depending on the environment of the individual. Certain psychological factors  can also trigger obesity such as stress, depression and simply boredom. These lead to the spate of binge eatings which can lead to weight gain. The nutritional factors such as intake of diets rich in fats and sugars or physiological factors such as hypothalamic lessions (due to tumour, trauma or inflammation) also lead to obesity. The latter may lead to imbalance of hunger and satiety signals and hence prolonged urge to eat. 

                The social and cultural factors also increase risk of obesity. Further, erratic timings or no-meal-spells upset the natural body rhythms, and in turn the neurotransmitters regulating energy balance and these can lead to obesity. Excess weight gain also occurs with the use of certain medications particularly antipsychotics, antidepressants, antihistaminics, antidiabetics, oral contraceptives etc.

Treatment of Obesity

                The ultimate goal of treatment is to achieve a healthier weight and approximately 10% decrease in weight significantly reduces the risk of comorbidities associated with obesity. The five medically-accepted currently available treatment modalities for obesity are diet modification, exercise, behavior modification, drug therapy and surgery. All of these modalities alone or in combination are capable of inducing weight loss sufficient to produce significant health benefits in many obese persons.

1. Diet modification

                 Calorie restriction remains the mainstay for the treatment of obesity. The ultimate goal is to achieve a healthier weight by adopting a healthful diet with an energy intake that does not exceed energy expenditure. These diets are low in fat and carbohydrates and provide adequate amounts of food groups including whole grains and cereals, fruits and vegetables. The use of dietary fibres also help mediate weight loss by improving blood glucose levels through enhanced insulin effects and reducing the number of calories absorbed by the body. The more restrictive diets may produce rapid weight loss but they increase the risk of non-compliance, cause greater loss of lean body mass and cause other complications as transient fatigue, dizziness, hair loss, gall stones, cardiac problems etc.

2. Behavior modification

                  Behavioural modification is an effective means to control the eating patterns of the patients. This involves identifying cues that trigger the desire to consume excess food and then work around the psyche of the patient to control this extra gorging. These techniques are useful for mildly to moderately obese persons and include:

i) Self monitoring: This involves systematic observation and recording of target behaviours. The patient maintains the food and activity diaries to record caloric intake (amount and type of food groups eaten, situation in which overeating is common) and duration and intensity of exercise. It also involves the recording of situational factors,behaviours, thoughts, moods, feelings that occur before, during and after attempts at prudent eating and exercise.

ii) Stimulus control: This involves modifying the environmental factors that lead to inappropriate eating or exercise. Examples of this modality include keeping away from high-fat foods, eating at specific times and places, and setting aside a time and place to exercise.

iii) Cognitive restructuring: The technique focuses on strategies to counter the thoughts, moods, diets and social pressures to be thin.

iv) Stress management: Stress is a primary predictor of relapse and over-eating. Various stress management techniques such as diaphragmatic breathing, progressive muscle relaxation, or meditation helps to overcome various health-related problems.

v) Social support: This gives the patient greater self-acceptance, develop new norms for interpersonal relationships and manage stressful work or family situations.

3. Physical activity and exercise

                   Like calorie restriction, exercise is a fundamental, albeit underutilized modality for weight control. Exercise expedities weight loss and also preserves the muscle tone. The addition of an exercise program to diet modification results in more weight loss than dieting alone and is especially helpful in maintaining weight loss and preserving lean body mass. Regular exercise increases the basal metabolic rate and this becomes particularly important as the metabolic rate declines slightly each year as people age. Therefore, unless there is a serious contraindication, most obese people should exercise regularly.

4. Surgery

                    Surgery is considered the treatment of choice for well informed and motivated severely obese (>100% overweight or BMI>40) adults who failed to respond to medical weight control. Surgery is also considered for those with the less severe obesity (BMI between 35 and 40) afflicted with disabling joint disease, pulmonary insufficiency, hypertension or diabetes mellitus. These surgical procedures can decrease food intake (gastric procedures - jaw wiring, vertical banded gastroplasty, gastric stapling), or affect calorie absorption (intestinal shunting, biliopancreatic bypass) or remove excess fat (lipectomy, liposuction). Lipectomy and liposuction are useful in individuals who have unusual localized bulges of body fat. The vertical banded gastroplasty restricts food intake by limiting gastric volume whereas the Roux-en-Y gastric bypass operation not only limits the gastric volume but also results in stomach contents bypassing the distal stomach, duodenum, and proximal jejunum. These techniques are very useful to treat morbid obesity. Although some malabsorption of nutrients occurs, most of the weight loss is attributed to delayed gastric emptying and a feeling of fullness that cause the patients to limit food intake. Both these procedures can be reversed at a later date if required. Weight loss following either of these operations is initially rapid and reaches a plateau at 18 to 24 months. A slight degree of weight regain is common by 2 to 5 years after surgery. Surgery also produces impressive effect on the comorbid conditions. There is marked improvement in glucose tolerance often with amelioration of Type II diabetes, allowing patient to reduce or discontinue insulin. Weight-reduction surgery ameliorates hypertension as well as sleep apnoea, produces a decrease in cholesterol and triglycerides and an increase in high-density (HDL) lipoproteins, improves psychosocial functioning and also increases life expectancy.

5. Drug treatment

                    The non-pharmacological treatments for obesity are beneficial in inducing weight loss, improving risk factors and comorbidities but with them the reduction in weight is often moderate and patients rapidly regain weight. Therefore, the supplementation with drugs is receiving attention and has lead to a multi-million pound annual market for these drugs. But still the pharmacological treatment should be restricted to specific cases in which associated clinical risks warrant more urgent intervention. The British National Formulary has recommended that "drugs (for obesity) should only be considered for those with a BMI of 30 or greater if supervised diet, exercise, and behaviour modification fail to achieve a realistic reduction in weight".