About BMI and Obesity

Obesity and Illness

Does Weight Loss
equal Health Gain?

Obesity and Illness

How much does obesity reduce your life expectancy?

Obesity has a great effect on your life expectancy. A large decrease in life expectancy is seen in people who are very overweight and/or obese. In fact, there is about a 20% reduction in life expectancy when you are obese. So if you assume a 20 year-old white male with a normal BMI could live for another 58 years, to around 78 years old; if the same person had a very high BMI, for example a BMI of over 45, he would on average live only until 65 years old. That's a reduction of 13 years!

The table below shows another example of how obesity can reduce a person's life expectancy:

Table: Years lost from the age of 40 years old relative to persons with the normal weight individuals

What are the obesity related illnesses?

Diseases and conditions associated with obesity are sometimes referred to as co-morbid illnesses.

The table below shows a number of different diseases and indicates the risk of developing certain conditions if you are obese. Relative Risk (RR) is the statistic used here to compare the risk of developing a disease. Relative risk indicates the likelihood that an obese person will have one of these diseases to the likelihood that a normal weight person will have one of these diseases. The higher the number the more likely the disease is to occur if you are obese.

Table: Diseases and conditions associated with obesity