PHILADELPHIA (CBS) – Researchers say more than 50 million Americans who are classified as overweight or obese based on their BMI (body mass index) are actually healthy.

Scientists at UCLA used data from the 2005-2012 National Health and Nutrition Examination Survey to examine whether BMI was connected to true health markers such as blood pressure, triglyceride, cholesterol, glucose, insulin resistance and C-reactive protein data.

According to the report, nearly half of overweight individuals and 29 percent of obese people were metabolically healthy while 30 percent of “normal” weight individuals are actually unhealthy.

This is an important finding because the U.S. Equal Employment Opportunity Commission has proposed rules that would let employers penalize their staff for as much as 30 percent of their health insurance costs if they don’t satisfy health criteria, including meeting an approved BMI, researchers say.

Healthcare policymakers should consider the unintended consequences of relying solely on BMI, and researchers should seek to improve diagnostic tools related to weight and cardiometabolic health, according to the report.