Cause of obesity

Problem of obesity

What is BMI?

What is morbid obesity?

Metabolic Syndrome

Options of weight reduction

Cause of obesity

Weight gain and obesity are caused by consuming more calories than the body needs – most commonly by eating a diet high in fat and calories, being sedentary or both. However, the imbalance between calories consumed and calories burned can also be caused by a number of different obesity-related factors, including genetic, hormonal, behavioral, environmental and even cultural. It is important to remember that obesity is not always simply a behavioral issue.

Genetic factor
Obesity tends to occur in family and it is difficult to separate hereditary cause and environmental cause within an obese family. The discovery of Obese Gene (Ob gene) in 1995 provide an important evidence of genetic predisposition of obesity. Ob gene governs the production of hormone "Leptin" (Latin – lepti = lean) from fat cells. This hormone acts within our brain and control our appetite (satiety) and efficiency of energy expenditure (metabolic rate). Obese peoples tend to be less responsive to this "lean hormone" which leads to fat accumulation.

Environmental factor
Apart from genetic factor, environmental influence places an important role in development of obesity. Environmental factors include lifestyle and eating habits. In modern society, our choice of food is largely dependent on taste and convenience rather than nutritional value. High calories diet (high fat, high carbohydrate) is the main cause of excessive calorie intake. As we cannot modify our genetic makeup, weight control is largely depends on our diet and daily behavior. Effective ways of weigh control includes:
1. Avoids high fat diet (ice-cream, deep fry oily stir dishes)
2. Avoids junk food and gluttonous eating habit
3. Increase energy expenditure with regular exercise (>30min / day; >150min / week)

Psychological and behavioral factor
Our psychological status is closely related to our eating behavior. Over-eating behavior is a common manifestation of anxiety, depression, stress and loneness. In extreme, some people will develop more severe psychiatric problem such as Bulimia Nervosa and Binge Eating Disorder. Patients with eating disorder will find difficulty in control their eating habit and sometimes require special medical and psychological attention.

Others metabolic disease
Illnesses can also lead to obesity. Some of these include hypothyroidism, Cushing's syndrome, depression, and other neurological problems. The use of steroids and certain antidepressants can also lead to weight gain.

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