CHICAGO (WLS) --A flavor-boosting additive is raising new health concerns. It's an ingredient common in processed foods - but manufacturers do not have to tell you how much is added.
Most of us have heard the warnings about sodium in food, but what about phosphates? The food additive is classified as a safe ingredient, but some local researchers believe we may be getting too much.
Carla Wills is a survivor, and now she's a savvy grocery shopper.
"I have a fear that what's OK today may not be OK next year," she said.
She is one of the lucky few. In 2008, she survived what is known as a "widow maker" heart attack.
"I had a 100 percent in my left atrium artery blocked," Wills said.
She knows to look out for known trouble makers such as excess sodium and trans fats. Now, she's keeping on eye on something new: phosphates.
"It's stopped me from buying a lot of packaged lunch meats," Wills said.
One estimate finds nearly a third of Americans eat twice as much phosphorus as recommended. It's the excess that may increase the risk of chronic diseases.
A 2013 study of thousands of healthy adults found that eating a high amount of phosphorus was linked to more deaths.
"There could be some harmful effects but, you really need to do more studies to actually prove there is a cause and effect there," said Dr. Alex Chang, Geisinger Medical Center.
Phosphates are derivatives of the element phosphorus, which is found naturally in everything from plants to meat and it helps make our cells healthy. But it's the excessive use as an additive in processed foods that's raising red flags.
"Phosphates make things taste good, it makes it's shelf life longer and it makes its appearance better," said Dr. Myles Wolf, lead investigator at Northwestern Medicine.
Northwestern Medicine researchers just launched a new study into excess phosphate consumption and potential heart damage.
"Phosphate in and of itself seems to have toxicity on the blood vessels and the phosphate regulating hormone FGF23 seemed to primarily target the heart itself," Wolf said.
"I think it doesn't hurt to actually look and keep looking at these components these food additives to make sure that what we though we knew 10 years ago is still true today," said Robert Brackett, Ph. D, director of food safety and health at IIT.
The Food and Drug Administration classified phosphates as a "generally recognized as safe" ingredient.
But for anyone who wants to avoid consuming too much, it's not so easy to tell what you are taking in. Phosphate additives are included on the ingredient list, but the exact amount isn't required.
"In the absence of an opinion that there is a significant health risk I think consumers ought to be confident that what they are eating is fine," Brackett said.
"Until I get a clearer understand of it I'm not sweating bullets, but I'm keeping aware of it," Wills said.
Right now there's no definitive research showing phosphate additives directly cause medical issues in healthy people.
Still, some consumer and medical organizations are encouraging the FDA to require the amount be listed on nutrition labels.