Difference Between Obesity and Overweight

Obesity vs Overweight


How common is Overweight and Obesity

Excessive accumulation of fat resulting in above normal body weight and impairment of health is collectively known as obesity and overweight. Although obesity and overweight are preventable, there are more than 1.5 billion adults above the age of 20 who are overweight. Over 200 million males and 300 million females are obese according to 2008 data. Children under the age of five who were overweight amounted to over 43 million in 2010 [1].

Effects of obesity and overweight

According to World Health Organization’s non communicable disease risk categorization, obesity and overweight is the fifth most important risk factor for cardiovascular diseases and diabetes. 65% of the world’s population is sequestered in countries with a high morbidity and mortality due to overweight and obesity. Childhood overweight and obesity are known risk factors for increased prevalence of adult cardiovascular diseases, diabetes. Therefore, year 2011 has been declared for prevention of non communicable diseases and the World Health Organization general summit will table risk factor prevalence, prevention and control.

Double burden of obesity and overweight

Non communicable diseases are a grave issue due to its double burden. In addition to the disease management cost, there is a loss of income due to loss of worker-time. Existence of obesity and overweight together with under nutrition is now a common finding in low to middle income countries.

Causes of overweight and obesity

Cause for overweight and obesity is a positive energy intake balance. The net intake of energy and expenditure need to be balanced according to the activity level, age and sex. Excessive intake of food and lack of physical exercise result in a positive energy balance. Energy balance is affected by social, cultural factors. Policy issues concerning health, urban planning, agriculture, marketing, education and economy will support or deter it.

Difference between overweight and obesity

Obesity and overweight are medical definitions derived from the body mass index calculation. Body mass index is a mathematical representation of weight for height. The formula is as follows.

Body Mass Index = Weight in Kilo grams (Kg) / Height in meters squared (m2)

Normal body mass index range is 18.5 Kgm-2 to 25 Kgm-2. Overweight is defined as body mass index between 25 – 30 Kgm-2. Obesity is defined as body mass index above 30 Kgm-2.

Application of obesity and overweight definitions

Body mass index is a population level indicator, which can be used for screening and monitoring purposes. As weight gain and loss are multifactorial, body mass index and thereby, definitions of overweight and obesity should be used as a part of a spectrum of indices.

Prevention of overweight and obesity

Prevention of obesity and overweight can be strategized according to risk factor and disease existence. Primordial prevention is taking steps to prevent while there are no discernible risk factors. Primary prevention is done in the presence of risk factors before the occurrence of disease. Secondary prevention is done to prevent complications. Tertiary prevention is done to prevent mortality and morbidity in the presence of complications. Common strategies for prevention are health education, health promotion, empowerment of health care staff, community members and policymakers plus other stakeholders.


1. World Health Organization factsheet, 2011, Viewed 13th August 2011