Obesity and overweight are defined as an accumulation of excess body fat, to an extent that may impair health. A crude population measure of excess fat is the body mass index (BMI), a person’s weight (in kilograms) divided by the square of his or her height (in metres). WHO defines overweight as a BMI of 25 or more, and obesity as a BMI of 30 or more. These cut-off points can provide a reference for individual assessment.

There is also evidence that, on a population level, the risk of chronic disease increases progressively as average BMI increases above 21. A high body mass index is a major risk factor for a number of chronic diseases, including cardiovascular diseases, cancer and diabetes.

• Patient's appearance is sufficient to arrive at a diagnosis in most cases. Obesity is determined based on an individual's body mass index (calculated with reference to the person's height and weight).
  
  Large body frame.
  Difficulty in doing daily activities. 
  Lethargy 
  Breathlessness

Obese men and women are more at risk for many diseases:

• Diabetes
• Gall bladder disease
• Heart and blood vessel problems, such as stroke and coronary heart disease
• Cancer
• High blood pressure
• Bone-related arthritis
• Abnormal levels of fat in your blood
• Gout, and
• Sleep apnea (interrupted breathing while you sleep) syndrome