Some 54 million people are mislabeled by Body Mass Index (BMI) as overweight or obese, a new study suggests. In reality, those people are actually healthy.

Body Mass Index (BMI) is a wide-spread measure of a person’s weight in kilograms (1 kilogram = 2.2 pounds) divided by the person’s square height in meters.

Scientists based at the University of California studied a possible link between BMI and other health determiners such as cholesterol levels, blood pressure, triglycerides and glucose.

The researchers used data dating back from the 2005-2012 National Health and Nutrition Examination Survey. Turns out, some 54 million people who are considered overweight or obese by their BMI measurements are actually metabolically healthy.

The study found that 29% of Americans labeled by BMI as overweight or obese are actually healthy, while, at the same time, 30% of those who were healthy according to BMI are actually unhealthy based on other health determiners.

The results of the study also indicate that using BMI as the main determination of health means that 74.9 million adults in the United States are being mislabeled as healthy or unhealthy.

According to researchers, companies that use BMI to find out health insurance costs for their employees could be unjustifiably charging their healthy workers more for medical insurance.

Equal Employment Opportunity Commission (EEOC) has recently proposed a rule that companies could penalize employees with BMIs’ upper limit of the ‘healthy’ range by making them pay higher premiums.

BMI has long been criticized for its flaws and inaccuracies. However, BMI checks are still in wide use by American companies to determine their workers’ health insurance costs.

“Policymakers should consider the unintended consequences of relying solely on BMI,” the researchers wrote in the study, “and researchers should seek to improve diagnostic tools related to weight and cardiometabolic health.”