Globally there are almost 1 billion overweight people and 300 million of them are obese. Obesity health risks such as cardiovascular disease, stroke, type 2 diabetes and hypertension. The key factor in this exponential increase in the obesity can be attributed to changing food habits and sedentary life styles. People are consuming more and more foods rich in saturated fats and sugars. At the same time, there is less and less physical activity.
There are various means to decide if the person is obese or not. The most commonly used method to do so is Body Mass Index (BMI). BMI is the ratio of weight in pounds to the square of height in meters.
There is a range to classify people as slim, heavy, overweight and obese. It is generally believed that people who have ideal BMI are not obese. But, at times, BMI can be misleading. If you are a regular gym user, you basically tone up your muscles everyday. So you will have more weight of muscles. This increase in weight is due to muscles and not fat. Now, if you calculate your BMI, it may say that you BMI is high or that you are obese, which is actually not the case. No matter how much you work out in the gym, your BMI will not reduce.
The calculation of BMI is not very accurate in few cases such as pregnant women, for people who are less than five feet tall or people having lot of muscle mass. Being overweight means different things to different people.
The BMI is used by doctors to assess patients that are overweight or obese. It is a very good measure for describing relative weight for any given height and measures your overall total body fat content. But, It does not differentiate between people with too much fat and athletic, muscular body type people. Thus, you should really use BMI in conjunction with other body composition assessments. It actually overestimates body fat in people who are very muscular, such as body builders, or those who have lost a lot of muscle mass, such as the elderly or ill.