Obesity is bad but it might extend your life if you are at a high risk of heart failure.

The good part about having a large waist size is that it may lower your chances of adverse outcomes after a heart surgery.

Okay, so maybe it was your waist size (along with genetic factors) that put you on the operating table in the first place, but once there it is the same body fat that'll keep you alive.

Researchers call this as the "obesity paradox" where being obese puts a person on higher risk of heart diseases but over time offers protective benefits.

"We knew that obesity might provide a protective benefit for heart failure patients, but we didn't know whether this obesity paradox applied specifically to women with heart failure, as well as men — and it does," said Dr. Tamara Horwich, assistant professor of cardiology at the David Geffen School of Medicine at UCLA and senior author of the study.

Previous research has shown that people with high Body Mass Index (BMI) have a higher chance of surviving after treatment for a heart disease.

The present study found that in a group of nearly 3,000 people with advanced heart failure, men with higher BMI and larger waist size were less likely to have a heart transplant or a ventricular assist device placement than men with normal waist size and BMI. Women, too, had a significantly lowered risk of suffering from adverse health outcomes if their waist was larger.

The study was conducted over a period of two years, where researchers found that heart failure patients who were overweight or obese had a statically higher chance of surviving than people with normal weight. This applied to both men and women.

"The study provides us with more insight about how both genders of heart failure patients may be impacted by the obesity paradox. Heart failure may prove to be one of the few health conditions where extra weight may prove to be protective," said Horwich,

"The study also demonstrates how BMI and waist circumference can be used together to provide a more accurate measure of fat in the body to help determine obesity and assess risk," said Adrienne L. Clark, a resident in the department of medicine at the Geffen School of Medicine and lead author of the study.

The study is published in The American Journal of Cardiology.