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Obesity




  • What is obesity?
Obesity is a chronic disease that affects many people and often requires long-term treatment to promote and sustain weight loss. "Obesity" specifically refers to an excessive amount of body fat. "Overweight" refers to an excessive amount of body weight that includes muscle, bone, fat, and water. As a rule, women have more body fat than men.

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  • How is obesity measured?
Measuring the exact amount of a person's body fat is not easy. There are simpler methods to estimate body fat. One is to measure the thickness of the layer of fat just under the skin in several parts of the body. Another involves sending a harmless amount of electricity through a person's body. Results from these methods, however, can be inaccurate if done by an inexperienced person or on someone with extreme obesity.

There are simpler methods to estimate body fat. One is to measure the thickness of the layer of fat just under the skin in several parts of the body. Another involves sending a harmless amount of electricity through a person's body. Results from these methods, however, can be inaccurate if done by an inexperienced person or on someone with extreme obesity. Because measuring a person's body fat is difficult, health care professionals often rely on other means to diagnose obesity.

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  • What causes obesity?
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.

Three factors that causes obesity:
  • Genetic Factors
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.
  • Environmental and Social Factors
Environment strongly influences obesity. Environment includes lifestyle behaviors such as what a person eats and his or her level of physical activity. Environment also includes the world around us—our access to places to walk and healthy foods, for example. Today, more people drive long distances to work instead of walking, live in neighborhoods without sidewalks, tend to eat out or get “take out” instead of cooking, or have vending machines with high-calorie, high-fat snacks at their workplace. Our environment often does not support healthy habits.

In addition, social factors including poverty and a lower level of education have been linked to overweight. One reason for this may be that high-calorie processed foods cost less and are easier to find and prepare than healthier foods, such as fresh vegetables and fruits. Other reasons may include inadequate access to safe recreation places or the cost of gym memberships, limiting opportunities for physical activity.

Although you cannot change your genetic makeup, you can work on changing your eating habits, levels of physical activity, and other environmental factors. Try these ideas:
  • Learn to choose sensible portions of nutritious meals that are lower in fat.
  • Learn to recognize and control environmental cues (like inviting smells or a package of cookies on the counter) that make you want to eat when you are not hungry.
  • Engage in at least 30 minutes of moderate-intensity physical activity (like brisk walking) on most, preferably all, days of the week.
  • Take a walk instead of watching television.
  • Eat meals and snacks at a table, not in front of the TV.
  • Keep records of your food intake and physical activity.
  • Other Factors
Some illnesses may lead to or are associated with weight gain or obesity. These include:
  • Hypothyroidism, a condition in which the thyroid gland fails to produce enough thyroid hormone. It often results in lowered metabolic rate and loss of vigor.
  • Cushing's syndrome, a hormonal disorder caused by prolonged exposure of the body's tissues to high levels of the hormone cortisol. Symptoms vary, but most people have upper body obesity, rounded face, increased fat around the neck, and thinning arms and legs.
  • Polycystic ovary syndrome, a condition characterized by high levels of androgens (male hormone), irregular or missed menstrual cycles, and in some cases, multiple small cysts in the ovaries. Cysts are fluid-filled sacs.
Lack of sleep may also contribute to obesity. Recent studies suggest that people with sleep problems may gain weight over time. On the other hand, obesity may contribute to sleep problems due to medical conditions such as sleep apnea, where a person briefly stops breathing at multiple times during the night.

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  • What are the consequences of obesity?
Health Risks:

Obesity is more than a cosmetic problem. Many serious medical conditions have been linked to obesity, including type 2 diabetes, heart disease, high blood pressure, and stroke. Obesity is also linked to higher rates of certain types of cancer. Men who are obese are more likely than nonobese men to develop cancer of the colon, rectum, or prostate. Women who are obese are more likely than nonobese women to develop cancer of the gallbladder, uterus, cervix, or ovaries. Esophageal cancer has also been associated with obesity.

Other diseases and health problems linked to obesity include:
  • Gallbladder disease and gallstones.
  • Fatty liver disease (also called nonalcoholic steatohepatitis or NASH).
  • Gastroesophageal reflux, or what is sometimes called GERD. This problem occurs when the lower esophageal sphincter does not close properly and stomach contents leak back—or reflux—into the esophagus.
  • Osteoarthritis, a disease in which the joints deteriorate. This is possibly the result of excess weight on the joints.
  • Gout, another disease affecting the joints.
  • Pulmonary (breathing) problems, including sleep apnea, which causes a person to stop breathing for a short time during sleep.
  • Reproductive problems in women, including menstrual irregularities and infertility.
Psychological and Social Effects:

Emotional suffering may be one of the most painful parts of obesity. Many people think that individuals with obesity are gluttonous, lazy, or both. This is not true.

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  • How is obesity treated?
The method of treatment depends on your level of obesity, overall health condition, and readiness to lose weight. Treatment may include a combination of diet, exercise, behavior modification, and sometimes weight-loss drugs. In some cases of extreme obesity, bariatric surgery may be recommended. Remember, weight control is a life-long effort, and having realistic expectations about weight loss is an important consideration. Eating a healthful diet and getting at least 30 minutes of moderate-intensity physical activity on most, preferably all, days of the week have important health benefits. Sixty minutes of physical activity a day may be required to prevent gradual weight gain in adulthood. Previously overweight and obese individuals are encouraged to get 60 to 90 minutes of exercise a day to sustain weight loss.


Information obtained from National Institute of Health
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