Societal misconceptions about weight and the preferences have lead to the misconceptions that being overweight and obese are the same. The two are in distinctive levels in every way including; the weight, health problems, and methods of losing weight.

Both Overweight and Obesity imply a condition of excess weight in a human being. The term Overweight is generally used to indicate the excess weight while Obese refers to excess fat. Being overweight means having more body weight than is considered normal or healthy for one’s age or build. On the other hand, Obesity is the condition of being obese, i.e., excess amount of body fat. While an overweight person will carry excess weight, he may or may not have excess accumulation of fat.

Sourced from: http://www.diffen.com/difference/Obesity_vs_Overweight

Overweight and obese persons have excess amounts of weight or fat. The most common method of separation between overweight and obese persons is by the use of the Body Mass Index (BMI).

Body Mass Index, or BMI, is used as a screening tool for overweight or obesity. Body Mass Index (BMI) is a person’s weight in kilograms divided by the square of height in meters. A high BMI can be an indicator of high body fatness. BMI can be used as a screening tool but is not diagnostic of the body fatness or health of an individual.

• If your BMI is less than 18.5, it falls within the underweight range.

• If your BMI is 18.5 to 24.9, it falls within the normal or healthy weight range.

• If your BMI is 25.0 to 29.9, it falls within the overweight range.

• If your BMI is 30.0 or higher, it falls within the obese range.

Sourced from: http://www.cdc.gov/obesity/adult/defining.html

The BMI is a good tool to screen for obesity and overweight persons. It allows for the classification of obesity in three levels.

If you are obese, your doctor might talk about the categories of obesity:

• Obesity level l: BMI of 30-34.9

• Obesity level ll: BMI of 35-39.9

• Obesity level lll: BMI of 40 or higher, which some also call “morbid” obesity

Sourced from: http://www.webmd.com/diet/am-i-obese

While BMI is a good way of identifying whether a patient is obese or overweight, and their classifications into the categories of obesity as level I, II, or III. It is considered as the first tool of confirmation, but not the last word. The health practitioner should also utilize confirmatory techniques.

• Check Your Waist Size

The CDC recommends that doctors use BMI a first step to screen adults for weight problems. Your doctor should also consider other things, like how fit you are.

Get a tape measure and wrap it around your belly. If your waist is more than 35 inches around and you are a woman, or if it is more than 40 inches and you are a man, you might have too much belly fat. Research shows that carrying extra fat around your stomach is unhealthy, no matter what your BMI is.

• The Edmonton Scale

Obesity experts also use the Edmonton obesity staging system. It takes BMI a step further by relating it to your health. There are five stages:

Stage 0: You do not have any health problems related to your weight.
Stage 1: Any weight-related health problems are mild (such as borderline high blood pressure or occasional aches and pains).
Stage 2: You have an obesity-related chronic disease, such as high blood pressure, type 2 diabetes, sleep apnea, or osteoarthritis, and you have moderate problems doing daily activities or feeling well.
Stage 3: You have had serious weight-related problems, such as a heart attack, heart failure, stroke, or other conditions.
Stage 4: This is the most severe level of weight-related chronic health conditions, which are extreme and life threatening.

Sourced from: http://www.webmd.com/diet/am-i-obese?page=2