Money expert Clark Howard steps on a bathroom scale every day to monitor his weight, which is something he has done since he dropped about 30 pounds a decade ago.

But can you always trust the number on the scale when it comes to overall health? Not according to new research.

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Most Americans are overfat, study finds

A study published in the journal Frontiers in Public Health said that even if you’re not considered overweight or obese by traditional measurements, you may be overfat.

“The term overfat refers to the presence of excess body fat that can impair health, even for normal weight non-obese individuals,” according to the study’s authors. “Excess body fat is associated with cardiometabolic dysfunction, a clinical situation that can progressively worsen, potentially leading to various common disease risk factors, chronic diseases, increased morbidity and mortality, and reduced quality of life.”

The authors of the study argue that relying on BMI (body mass index) to determine whether someone is overweight or obese may misclassify 50% of patients who still have excess body fat, particularly around the belly.

In the United States, the study found that 90% of men, 80% of women and 50% of children are overfat.

How do you know if you’re overfat? Take a measuring tape and put it around your waist at your belly button. You want the measurement to be half your height or less for a healthy fat level.

For example, someone 68 inches tall with a 34 inch waist isn’t overfat — but at 35 inches they would be.

Dr. Oz recently stopped by NBC’s “Today” to demonstrate. He emphasized that even if the number on the scale looks good, it’s the fat around the belly that concerns him.

Belly fat has been linked to multiple health problems, including type 2 diabetes and heart disease, Dr. Oz said.

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