Palm Oil Not a Healthy Substitute for Trans Fats

Manufacturers are now required to state on food labels the amount of trans fatty acids, also called hydrogenated fats, in packaged foods. Both trans fatty acids and saturated fatty acids are associated with elevated heart disease risk factors.

Now, authors of an Agricultural Research Service (ARS)-supported study published in early 2006 have addressed the question of whether palm oil, whose functional characteristics are similar to trans fats, would be a good substitute for partially hydrogenated fat.

Trans fatty acids (trans fats) are created during a hardening process called hydrogenation, which serves to make oils suitable for use in products that require solid fats, such as baked goods and breakfast bars. The clinical trial was designed to compare—on heart disease risk—the effect of four different oils as they are commonly consumed.

Lead scientist Alice H. Lichtenstein and colleagues conducted the study. She is with the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University in Boston, Mass.

Fifteen adults, both male and female, volunteered for the study. Their levels of LDL "bad" cholesterol were moderately high at 130 milligrams per deciliter of blood or above, and all were aged 50 or older. They each consumed each of four 35-day experimental diets. The fats tested were partially hydrogenated soybean oil (moderately high in trans fat), palm oil (high in saturated fat), canola oil (high in monounsaturated fat), and soybean oil (high in polyunsaturated fat).

The findings suggest that consuming either of the diets enriched with equivalent high amounts of palm oil or partially hydrogenated soybean oil would result in similar unfavorable levels of LDL cholesterol and apolipoprotein B (a protein, attached to fat particles, that carries bad cholesterol throughout the bloodstream). That's when compared to consuming either of the diets enriched with canola and soybean oils high in monounsaturated and polyunsaturated fats, respectively.

The results suggest that palm oil would not be a healthy substitute for trans fats by the food industry, the authors wrote.

Read more about this research in the April 2009 issue of Agricultural Research magazine.

ARS is the principal intramural scientific research agency of the U.S. Department of Agriculture.