Research published in CDC’s journal Preventing Chronic Disease suggests manufacturer reduction of trans fatty acids (TFAs) has slowed over time, and progress varies by food type and parent company. Because consuming TFA is harmful even at low levels, researchers urge manufacturers to renew efforts to discontinue or reformulate products containing TFA or partially hydrogenated vegetable oils (PHVOs).

Small quantities of TFAs occur naturally in meat and dairy products, but most TFA consumption comes from partially hydrogenated vegetable oils. The partial hydrogenation process converts vegetable oils to semisolid fats with attractive cooking, baking and frying properties. However, scientific studies have shown consumption of TFAs increases risk for cardiovascular and metabolic conditions. 

Researchers selected 360 products containing .5g TFA or more per serving and observed their labels annually from 2007 to 2011. Researchers also recorded levels of PHVO in 2011. Among the 270 products produced each year, TFA reduction slowed over time from 30.3 percent in 2007-2008 to 12.1 percent in 2008-2010 and to just 3.4 percent for 2010-2011.

The slowing pace of reductions resulted both from fewer reformulations of TFA-containing products and smaller TFA reductions among reformulated products. Reformulations also varied by product type and company, with some entirely or mostly eliminating TFA while others showed no significant changes.

Data from the National Health and Nutrition Examination Survey suggests US consumption of industrially produced (as opposed to naturally occurring) TFA declined between 2003 and 2006. Blood analysis shows a roughly 50 percent reduction of TFA exposure from 2000 to 2009.

Overall, evidence shows TFA consumption in the US is decreasing, but the pace, scale and extent of reduction efforts remain varied across product type and company.