Waistline could be secret to living longer

As if you need more reasons to watch your weight, a new report says the key to a longer life is all in the waistline.

In a study, researchers from City University London looked at two decades worth of data from about 300,000 adults. They say your waistline measurement should be no more than half your height in order to live a prolonged life.

According to their developed formula, this would mean the waist of a male adult who is 5'10" should be no larger than 35 inches. Similarly, a 5'4" woman's waist should measure 32 inches. An increase of as many as seven inches can trim more than one and a half years off his or her life.

Research linking waist size and mortality has been done before and all have come up with the same conclusion -- that excess fat around the waist can contribute to premature death.

But all the studies have also determined Body Mass Index, which is used in most current health predictions, is not necessarily an accurate representation of health by itself.

BMI is a tool used to measure the health of an individual by looking at their weight relative to their height. But it's often seen criticisms in the health community.

The Daily Mail quotes the study's lead author who says the new formula could better determine how the fat around the waistline affects high cholesterol, diabetes and heart disease. "People are living in false hope if they rely on their BMI figure. We have got to measure the right thing."

Other experts say BMI doesn't distinguish between fat and muscle. Because muscle weighs more than fat, the index might determine a muscular person to be obese. It also fails to account for the fact taller people might take up more space without necessarily being overweight or obese. The study was published in the Public Library of Science.

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