The Centers for Disease Control and Prevention (CDC) revealed Americans may be consuming more trans fat than they think.

The overall consumption rate of trans fat appears to be on the decline in the U.S., but very little research has been done on how much there actually is in foods, the CDC reported.

Researchers analyzed 4,340 top-selling US packaged foods and found nine percent contained partially hydrogenated oils; 84 percent of these products were labeled to contain zero grams of trans fat.

Trans fat consumption is linked to cardiovascular disease. The U.S. Food and Drug Administration (FDA) has "tentatively determined" that partially hydrogenated oils (PHOs), which are a major source of trans fat, are "generally recognized as safe" for consumption. The FDA is considering public comments to help settle the matter. If they decide to finalize the proposed change PHOs will not be allowed to be used in packaged items or restaurants.

To make their findings the researchers used a cross-sectional database of brand-name products developed for the National Salt Reduction Initiative (NSRI) in 2012. This contains food categories such as baked goods, frozen food, and snacks.

The researchers found 391 of the 4,340 products listed PHOs in their ingredient information; 61 of these products were listed as containing zero grams of trans fat.

The analysis showed trans fat is still prevalent in U.S. packaged food and much of it as not labeled as such

"Eliminating trans fat from US foods is possible, but removal has not been achieved through labeling requirements for packaged food: almost 1 in 10 products we examined contained PHOs. Although restricting the use of PHOs in packaged food would benefit consumers preparing foods at home, an FDA ruling would also help ensure that restaurant customers are protected from unknowingly consuming industrial trans fat," the CDC stated.