Monday, September 7, 2009

Obesity - A Global Epidemic | Bariatrics Surgery | Overweight and Obesity Issues | Aastha Healthcare | Super Speciality Center Hospital | India

About Obesity

Though we all use the terms "fat" and "obese" casually in conversation, there is a medical definition of the condition and yes, obesity is considered a health "condition." It is a term used to describe body weight that is much greater than what is considered healthy. Measuring the exact amount of a person's body fat is not easy. The most accurate measures are to weigh a person underwater or in a chamber that uses air displacement to measure body volume, or to use an X-ray test called Dual Energy X-ray Absorptiometry, also known as DEXA. These methods are not practical for the average person, and are done only in research centers with special equipment.

There are also other ways to determine if a person is obese, but experts believe that a person's body mass index (BMI) is the most accurate measurement of body fat for children and adults. Adults with a BMI greater than 30 are considered obese. You will be surprised to know that nearly one-thirds of the world's population is overweight. Rates of obesity are climbing. The percentage of children who are overweight has doubled in the last 20 years. The percentage of adolescents who are obese has tripled in the last 20 years. Morbid obesity is typically defined as being 100 pounds or more over ideal body weight or having a BMI of 40 or higher. Obesity becomes "morbid" when it significantly increases the risk of one or more obesity-related health conditions or serious diseases (also known as co-morbidities). According to the NIH Consensus Report, morbid obesity is a serious chronic disease, meaning that its symptoms build slowly over an extended period of time. Today 97 million Americans, more than one-third of the adult population, are overweight or obese. An estimated 5-10 million of those are considered morbidly obese.


W.H.O. CLASSIFICATION
BMI
Ideal weight 20-24.9
Overweight 25-29.9
Moderate obesity (class I) 30-34.9
Severe obesity (class II) 35-39.9
Morbid obesity (class III) 40-49.9
Super obesity 50 +

Overweight and obesity

Overweight and obesity are both labels for ranges of weight that are greater than what is generally considered healthy for a given height. For adults, overweight and obesity ranges are determined by using weight and height to calculate a number called the "body mass index" (BMI). BMI is used because, for most people, it correlates with their amount of body fat.

  • An adult who has a BMI between 25 and 29.9 is considered overweight.
  • An adult who has a BMI of 30 or higher is considered obese.
See the following table for an example.

Height
Weight Range
BMI
Considered
5' 9"
124 lbs or less
Below 18.5
Underweight
125 lbs to 168 lbs
18.5 to 24.9
Healthy weight
169 lbs to 202 lbs
25.0 to 29.9
Overweight
203 lbs or more
30 or higher
Obese

It is important to remember that although BMI correlates with the amount of body fat, BMI does not directly measure body fat. As a result, some people, such as athletes, may have a BMI that identifies them as overweight even though they do not have excess body fat. Other methods of estimating body fat and body fat distribution include measurements of skin fold thickness and waist circumference, calculation of waist-to-hip circumference ratios, and techniques such as ultrasound, computed tomography, and magnetic resonance imaging (MRI).

The obesity epidemic covered on TV and in the newspapers did not occur overnight. Obesity and overweight are chronic conditions. Obesity has already reached epidemic proportions in the United States. One in three Americans is obese. Obesity is also increasing rapidly throughout the world, and the incidence of obesity has nearly doubled form 1991 to 1998. Overall there are a variety of factors that play a role in obesity. This makes it a complex health issue to address.

Causes of obesity

Overweight and obesity are a result of energy imbalance over a long period of time. The cause of energy imbalance for each individual may be due to a combination of several factors. Obesity occurs when a person consumes more calories from food than he or she burns. Our bodies need calories to sustain life and be physically active, but to maintain weight we need to balance the energy we eat with the energy we use. When a person eats more calories than he or she burns, the energy balance is tipped toward weight gain and obesity. This imbalance between calories-in and calories-out may differ from one person to another. If you look carefully at the energy balance scale ( given below), weight gain is a result of extra calorie consumption, decreased calories used (reduced physical activity) or both. Personal choices concerning calorie consumption and physical activity can lead to energy imbalance.

In most cases, obesity results from genetic, environmental and psychological factors. But sometimes certain illnesses can also lead to weight gain or obesity, e.g. endocrine disorders (such as hypothyroidism and Cushing's syndrome) or neurological problems. In addition to this, certain drugs such as steroids and some antidepressants, can lead to either weight gain or increased appetite. Let us discuss these causes in details now:

Lifestyle Habits

Today, a changing environment has broadened food options and eating habits. Grocery stores stock their shelves with a greater selection of products. Pre-packaged foods, fast food restaurants, and soft drinks are also more accessible. While such foods are fast and convenient they also tend to be high in fat, sugar, and calories. Choosing many foods from these areas may contribute to an excessive calorie intake. This results in increased calorie consumption. If the body does not burn off the extra calories consumed from larger portions, fast food, or soft drinks, weight gain can occur.

Our bodies need calories for daily functions such as breathing, digestion, and daily activities. Weight gain occurs when calories consumed exceed this need. Physical activity plays a key role in energy balance because it uses up calories consumed. Despite all the benefits of being physically active, most of us are sedentary. Technology has created many time and labour saving products. Some examples include cars, elevators, washing machines, dishwashers, and televisions. Cars are used to run short distance errands instead of people walking or riding a bicycle. As a result, these recent lifestyle changes have reduced the overall amount of energy expended in our daily lives. According to the Behavioural Risk Factor Surveillance System, in 2000 more than 26% of adults reported no leisure time physical activity. The belief that physical activity is limited to exercise or sports, may keep people from being active. Another myth is that physical activity must be vigorous to achieve health benefits. Physical activity is any bodily movement that results in an expenditure of energy. But when we fail to do any physical activity, it just leads to calorie storage.

Environment

People may make decisions based on their environment or community. For example, a person may choose not to walk to the store or to work because of a lack of sidewalks. Communities, homes, and workplaces can all influence people's health decisions. Because of this influence, it is important to create environments in these locations that make it easier to engage in physical activity and to eat a healthy diet.

Genetics

Obesity tends to run in families, suggesting a genetic cause. However, families also share diet and lifestyle habits that may contribute to obesity. Separating genetic from other influences on obesity is often difficult. Even so, science does show a link between obesity and heredity.Genes can directly cause obesity in disorders such as Bardet-Biedl syndrome and Prader-Willi syndrome.

Drugs

Some illnesses may lead to obesity or weight gain. These may include Cushing's disease, and polycystic ovary syndrome. Drugs such as steroids and some antidepressants may also cause weight gain. A doctor is the best source to tell you whether illnesses, medications, or psychological factors are contributing to weight gain or making weight loss hard.

Certain illnesses

In addition, some illnesses may lead to or are associated with weight gain or obesity, e.g Hypothyroidism, a condition in which the thyroid gland fails to produce enough thyroid hormone. It often results in lowered metabolic rate and gain in weight. Another example is Cushing's syndrome. These kind of underlying medical conditions either make weight loss difficult or contribute to weight gain.

Effects of obesity

Severe obesity damages the body mechanically, metabolically, physiologically and has adverse effects on normal bodily function. This affects nearly every organ in the body in some way, and produce serious secondary illnesses, which may also be life-threatening. The cumulative effect of these co-morbidities can interfere with a normal and productive life, cause endless frustration and can seriously shorten life, as well. Some of the consequences of obesity have been given below:


Obesity is considered as 2nd leading cause of preventable death

  • Heart Disease

  • Severely obese persons are approximately 6 times as likely to develop heart disease as those who are normal-weighted. Heart disease is the leading cause of death in the United States today, and obese persons tend to develop it earlier in life, and it shortens their lives. Coronary disease is pre-disposed by increased levels of blood fats, and the metabolic effects of obesity. Increased load on the heart leads to early development of congestive heart failure. Severely obese persons are 40 times as likely to suffer sudden death, in many cases due to cardiac rhythm disturbances.

  • High Blood Pressure

  • Essential hypertension, the progressive elevation of blood pressure, is much more common in obese persons, and leads to development of heart disease, and damage to the blood vessels throughout the body, causing susceptibility to strokes, kidney damage, and hardening of the arteries.

  • High Blood Cholesterol

  • Cholesterol levels are commonly elevated in the severely obese -- another factor predisposing to development of heart and blood vessel disease. This abnormality is not just related to diet, but is an effect of the massive imbalance in body chemistry which obesity causes.

  • Diabetes Mellitus

  • Overweight persons are 40 times as likely to develop Type II, Adult-Onset, and Diabetes. Elevation of the blood sugar, the essential feature of Diabetes, leads to damage to tissues throughout the body: Diabetes is the leading cause of adult-onset blindness, a major cause of kidney failure, and the cause of over one half of all amputations.

  • Sleep Apnoea Syndrome

  • Sleep apnoea -- the stoppage of breathing during sleep is commonly caused in the obese, by compression of the neck, closing the air passage to the lungs. It leads to loud snoring, interspersed with periods of complete obstruction, during which no air gets in at all. The sleeping person sounds to an observer like he is holding his breath, but the sleeper is, himself, usually unaware that the problem is occurring at all, or only notices that he sleeps poorly, and awakens repeatedly during the night. The health effects of this condition may be severe, high blood pressure, cardiac rhythm disturbances, and sudden death.

  • Respiratory problems

  • Obese persons find that exercise causes them to be out of breath very quickly, during ordinary activities. The lungs are decreased in size, and the chest wall is very heavy and difficult to lift. At the same time, the demand for oxygen is greater, with any physical activity. This condition prevents normal physical activities and exercise, often interferes with usual daily activities, making even ordinary living difficult or miserable, and it can become completely disabling.

    Obesity is associated with a higher rate of asthma, about 3 times normal. Much of this effect is probably due to acid reflux which can irritate a sensitive airway and provoke an asthmatic attack.



  • Gallbladder Disease

  • Gallbladder disease occurs several times as frequently in the obese, in part due to repeated efforts at dieting, which predispose to this problem. When stones form in the gallbladder, and cause abdominal pain or jaundice, the gallbladder must be removed.

  • Stress Urinary Incontinence

  • A large heavy abdomen, and relaxation of the pelvic muscles, especially associated with the effects of childbirth, may cause the valve on the urinary bladder to be weakened, leading to leakage of urine with coughing, sneezing, or laughing. This condition is strongly associated with being overweight, and is usually relieved by weight loss.

  • Degenerative Disease of Lumbo-Sacral Spine

  • The entire weight of the upper body falls on the base of the spine, and overweight causes it to wear out, or to fail. The consequence may be accelerated arthritis of the spine, or "slipped disk", when the cartilage between the vertebrae squeezes out. Either of these conditions can cause irritation or compression of the nerve roots, and lead to sciatica -- a dull, intense pain down the outside of the leg.

  • Degenerative Arthritis of Weight-Bearing Joints

  • The hips, knees, ankles and feet have to bear most of the weight of the body. These joints tend to wear out more quickly, or to develop degenerative arthritis much earlier and more frequently, than in the normal-weighted person. Eventually, joint replacement surgery may be needed, to relieve the severe pain. Unfortunately, the obese person faces a disadvantage there too -- joint replacement has much poorer results in the obese, and complications are more likely. Many orthopedic surgeons refuse to perform the surgery in severely overweight patients

  • Venous Stasis Disease

  • The veins of the lower legs carry blood back to the heart, and they are equipped with an elaborate system of delicate one-way valves, to allow them to carry blood "uphill". The pressure of a large abdomen may increase the load on these valves, eventually causing damage or destruction. The blood pressure in the lower legs then increases, causing swelling, thickening of the skin, and sometimes ulceration of the skin. Blood clots also can form in the legs, further damaging the veins, and can also break free and float into the lungs -- called a Pulmonary Embolism -- a serious or even fatal event.

  • Emotional/Psychological Disease

  • Seriously overweight persons face constant challenges to their emotions: repeated failure with dieting, disapproval from family and friends, sneers and remarks from strangers. They often experience discrimination at work, and cannot enjoy theatre seats, or a ride in a bus or airliner. There is no wonder that anxiety and depression might accompany years of suffering from the effects of a genetic condition -- one which skinny people all believe should be controlled easily by will power.

  • Social Effects

  • Seriously obese persons suffer inability to qualify for many types of employment, and discrimination in employment opportunities, as well. They tend to have higher rates of unemployment, and a lower socioeconomic status. Ignorant persons often make rude and disparaging comments, and there is a general societal belief that obesity is a consequence of a lack of self-discipline, or moral weakness. Many severely obese persons find it preferable to avoid social interactions or public places, choosing to limit their own freedom, rather than suffer embarrassments.

    Facts about Morbidity due to untreated Obesity

    • Heart and Stroke foundation research shows that the number of deaths attributable
      directly to overweight and obesity has almost doubled over the last 15 yrs

    • 4,321 deaths in the year 2000 alone

    • US-based studies indicated that obese individuals can lose more than 10 years of
      life compared to their normal weight peers

    For more information, kindly visit :
    http://www.aasthahealthcare.com/Obesity-Global-Epidemic.htm

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