Avoiding foods made with partially hydrogenated vegetable oil has become a focus for many consumers. The partial hydrogenation of vegetable oil creates trans fat, a substance known to increase the risk for heart disease. While partially hydrogenated oils were once thought to be a healthier alternative to saturated fats, food manufacturers are now beginning to phase out these unhealthy fats. They can still be found in a variety of processed foods, however.

Fried Foods

The hydrogenation process was developed in the early 1900s, and one of the first consumer products to use the fat was vegetable shortening. In the late 1950s, the American Heart Association first recommended reducing dietary fats, specifically saturated fats. As a result, almost 30 years later in the 1980s, many fast-food restaurants began switching from saturated fat to partially hydrogenated vegetable oils for frying. At the time, partially hydrogenated vegetable oils were thought to be a healthier alternative to lard, which contains high amounts of saturated fat. As a result, today many fast-food restaurants still use trans fats to fry foods such as french fries and doughnuts.

Processed and Packaged Foods

Trans fats have a number of technical advantages, specifically for processed and packaged foods. One of the most notable advantages of partially hydrogenated oils is their ability to act as a preservative. This allows manufacturers to keep food on the shelves longer before it must be sold. In addition, trans fats can add texture and taste to foods, making them more desirable to consumers. Although partially hydrogenated vegetable oil can occur in nearly any processed or packaged food, it is routinely used in certain types of foods.

Major Offenders

The Centers for Disease Control and Prevention notes that Americans consume, on average, 1.3 grams of artificial trans fat per day, with major contributors being fried foods, frozen pizzas, cakes, cookies, margarine and spreads, pie, ready-to-use frosting and coffee creamers. The American Heart Association notes that biscuits, pastries and crackers are also especially likely to be made with partially hydrogenated oils. According to the U.S. Food and Drug Administration, snack foods such as microwave popcorn and baked goods typically contain trans fats.

Avoiding Partially Hydrogenated Oils

In November 2013, the FDA decided to ban the use of trans fats in foods due to their detrimental effects on health. But there will be a time period before the unhealthy fats are completely phased out of the food system. In the meantime, consumers can read nutrition facts labels and choose products with zero grams of trans fat. In addition, it's a good idea to check ingredient listings since "0 grams trans fat" can be listed by manufacturers if the product contains less than 0.5 gram of trans fat per serving. Avoid any products that use the words "partially hydrogenated."