Obesity is one of the root cause of many diseases and problems. Obesity leads to many life threatening disease. It is more common now a days in all group ages either children, adults, elderly. Main cause of obesity is poor healthy eating, consumption of junk food sedentary life style, lack of physical activity. These common life style behavior easily help to achieve obesity which further leads to many fatal diseases like cardiovascular diseases, hypertension, pulmonary disease, liver disorders etc. This article helps us to see the historical views of obesity, the growing obesity epidemic, pathophysiology of obesity, challenges associated with the critically ill obese patient, the obesity paradox that occurs in critical illness, nutrition support in the critically ill obese patient. Obesity is a complex disease involving an excessive amount of body fat. Obesity isn't just a cosmetic concern. It is a medical problem that increases your risk of other diseases and health problems, such as heart disease, diabetes, high blood pressure and certain cancers. Certain populations tend to have higher rates of obesity. Overweight and obesity are often accompanied by other chronic health conditions such as diabetes, heart disease, hypertension, certain cancers, and arthritis. Rural populations with a higher risk of obesity include those who are: Age 60 and above.