What are Trans Fatty Acids?

Three decades ago, when saturated fats and cholesterol were implicated as a major cause of heart disease, margarine was touted as the healthy alternative to butter, and we saw a huge push towards polyunsaturated oils like sunflower, corn oil, safflower oil, and sesame. Little did we know that these so-called healthier options would present us with one of the greatest hazards in the history of the human diet.

Introduced in 1911, the majority of trans fats found in the diet are created artificially by hydrogenation, bubbling hydrogen gas through vegetable oil. This process transforms some of the oil’s liquid (unsaturated) fat into a solid, stable fat, making it more useful for and extending the shelf life of processed foods, margarine, and baked goods… all at a lower cost to manufacturers. The price to consumers, however, is a different story.

Trans fats are linked to serious health conditions, and health authorities recommend zero consumption. They increase total blood cholesterol and LDL (the bad cholesterol) while lowering HDL (the good cholesterol). Trans fats also cause a rise in apolipoprotein A, another risk factor for heart disease, decrease insulin sensitivity affecting blood sugar balance, and enhance the production of pro-inflammatory hormones (prostaglandin E2) – bad news for arthritics or anyone with pain or allergies.

The dangerous fats are found in most margarines and shortening and in many processed foods including some you would not expect. Look for trans fat in cereals, granola bars, frozen pizza, fish sticks, puddings, peanut butter, instant soup mix, microwave popcorn, corn chips, pancake mix, many breaded foods (like chicken fingers and veal cutlets), and even powdered coffee creamer.

Unfortunately, trans fat is not always clearly indicated on food labels. Since very small amounts occur naturally in some meat and dairy products, foods with up to 0.49 grams of trans may be labeled as trans-fat free. Read labels carefully and avoid foods listing the term “partially hydrogenated vegetable oil” on the label. When liquid vegetable oil is fully hydrogenated, almost no trans fats remain. Full hydrogenation increases the amount of saturated fat, mostly in the form of stearic acid, but does not raise levels of LDL (“bad”) cholesterol. Fully hydrogenated fats are less harmful than partially hydrogenated fats.

Cooking and frying do not create trans fats, although heating oil alters its biochemical constitution producing other health risks.

Interesterified fats are the food industry’s response to an alternative for trans fat. The semi-soft fats have been chemically or enzymatically rearranged to alter their texture and/or nutritional profile. Replacing trans fats in pies and pastries, margarine and shortening, while interesterified fats appear safer, they have not been extensively tested. In 2007, a study found that interesterified fats and trans fats have similar health effects in that they increase the ratio of LDL to HDL cholesterol and increase blood sugar.

Non-hydrogenated spreads, such as Earth Balance, are available at your local grocery and health food store. Coconut butter is another option. It’s a saturated fat (solid at room temperature) but is cholesterol- and trans-fat free.