Obesity has reached epidemic proportions in India in the 21st century, affecting 5% of the country's population. The problem grows with affluence in society – 33% of the US population is obese.

What is obesity?

Obesity is a condition in which excess body fat  accumulates to such an extent that health is negatively affected

What is overweight?

Overweight is a condition in which the body fat is more than what is normal for an individual’s height and if unattended can lead to obesity. According to the National Institutes of Health (NIH) in the US, overweight refers to increased body weight that is at least 10 percent over a recommended weight relative to the individual. Overweight may not only be the result of increases in body fat, but lean muscle as well

What are the causes of obesity?

Diet, sedentary lifestyle, smoking, genetics, socio economic status, certain medical illness, depression, the micro organisms present in your stomach etc, all contribute to obesity. A large quantity of soda intake, fried foods, un healthy and reused oil cooking and lack of good diet fibres and vegetables, contribute to obesity.

How are obesity and overweight detected?

Both are based on your BMI or Body Mass Index, a measure of weight per unit height. A BMI under 25 is normal, 25-29.9 is overweight and anything beyond 30 is considered obese. Recent data has suggested that the cut off for overweight be reduced to 23, however, this is still under debate and anything less than 25 can be considered to be within the healthy scale.

What is BMI? How is it calculated?

The body mass index (BMI), or Quetelet index, is a statistical measurement which compares a person's weight and height. It is calculated by dividing your weight in kilograms by the square of your height in meters. So if your weight is 65 kg and your height is 1.7 meters (170 cm), your BMI will be 65/(1.7*1.7)= 22.5

Is BMI fool proof?

No. But for most of us, BMI is an accurate method of measuring the ideal weight for a given height.

When can BMI go wrong?

The only known defect in this calculation is that BMI depends on the whole weight and therefore does not distinguish between muscle and fat. Therefore BMI could go wrong in people with excessive muscle mass such as body builders.