Obesity, a worldwide phenomenon, today has surged to become one of the most deadly enemies of mankind, afflicting mostly the rich and the affluent. Obese in simple terms means excess body weight, usually in the absence of an underlying disease, except in a small number of cases where the condition originates from hormonal disturbances.

The terms overweight and obese are used synonymously by the commoner; however, there is some difference at the clinical level. A person can be considered overweight if his body weight is 10-19 per cent more than the normal or ideal body weight. However, when the body weight of a person is 20 per cent or more than his ideal body weight, he is considered obese. As we have seen previously, the ideal body weight for a person depends on his height, sex, age and body frame.

Thus, obesity is a condition of excess body weight and is usually the result of excess accumulation of fat in the body. When energy intake is persistently greater than energy expenditure, the result is gradual accumulation of fat deposits in the adipose tissue depots. Obesity does not happen in a day or a week. It is a gradual process taking place at snails pace when the individual constantly maintains a positive energy balance. A positive energy balance is usually the result of excessive energy intake.

High calorie and high fat foods pamper our taste buds to an extent that most individuals find it difficult to refrain from them in spite of being aware of their nutrient composition. The ignorant certainly cannot be blamed.

The other major culprit is modern urban life mechanisation and dependence on different tools has made life easy and increasingly sedentary. This has lead to the lowering of activity levels, of daily energy expenditure and thus of our total daily caloric needs. Increased calorie intake due to consumption of processed foods and decreased activity levels have together taken a toll, increasing the prevalence of obesity. Sometimes, of course obesity may also be the result of an interplay of hormones.

Obesity jeopardizes an individuals health in more ways than one. It imperils both body and mind of an obese individual. An obese individuals distorted body shape and appearance can be a source both of humiliation and discomfort. Many obese people complain of pain in the joints and may develop arthritis (osteoarthritis) because they have overburdened their knees and joints with their excess body weight. This is the most obvious health hazard that obesity invokes.

Obesity has been associated with a wide range of health problems. It contributes to increasing levels of lipids (fat) and cholesterol in the blood (hyperlipidemia and hypercholesterolemia respectively), leading to narrowing of blood vessels due to deposition of fatty materials in coronary arteries (atherosclerosis). This in turn causes the blood pressure levels to soar (hypertension) and increases the risk of heart attack (myocardial infarction) and strokes.

Obesity increases the risk of diabetes because it increases insulin resistance leading to glucose intolerance. Weight reduction helps many diabetic patients in controlling their diabetes. Obesity can also lead to pregnancy related and surgical complications. Obese individuals are also more likely to develop cancer. Certain cancers such as cancers of the gall bladder, endometrium, ovary, breasts and cervix in women, and cancers of the colon and prostate in men have been associated with excess body weight.

Extreme obesity can also cause respiratory insufficiency (hypoventilation) and may even result in sudden death during sleep. Thus, because of its association with several diseases, obesity decreases life expectancy.