For reducing cholesterol, corn oil better than olive oil, study suggests

Consuming vegetable oils has been associated with a reduction in total and low-density lipoprotein (LDL), or bad, cholesterol. But a study published in the January/February 2015 edition of the Journal of Clinical Lipidology suggests that between corn oil and extra virgin olive oil, the corn variety does a better job.

In a double-blind, randomized controlled crossover feeding study, researchers at Biofortis, a global clinical nutrition research team for dietary industry clients, found that corn oil lowered LDL cholesterol by nearly 11 percent, compared to extra virgin olive oil’s 3.5 percent reduction. Corn oil similarly lowered total cholesterol by over 8 percent compared to about 2 percent for extra virgin olive oil, according to a news release.

Fifty-four healthy men and women participated in the study and received four tablespoons of one of the oils in the same foods every day. Researchers measured the participants’ fasting blood samples before and after each treatment phase of the study.

Having high cholesterol is a risk factor for developing cardiovascular disease, which is the leading cause of death in the United States. According to the Centers for Disease Control and Prevention (CDC), about 600,000 Americans die of heart disease every year. That means the condition is responsible for 1 in 4 total annual deaths in the U.S.

Coronary heart disease costs the U.S. about $108.9 billion each year in health care services, medications and lost productivity, according to the CDC.

Study authors said corn oil was more effective at reducing cholesterol levels compared to extra virgin olive oil because it has a greater amount of plant sterols. Plant sterols are substances found in produce, nuts, seeds, legumes and vegetable oils.  A growing body of evidence suggests that they play a crucial role in maintaining a heart-healthy diet.

Compared to extra virgin olive oil’s 30 milligrams of plant sterols per serving, corn oil contains about 136 milligrams of plant sterols per serving, according to the news release.

"The study results suggest corn oil has significantly greater effects on blood cholesterol levels than extra virgin olive oil, due, in part, to the natural cholesterol-blocking ability of plant sterols," lead researcher Dr. Kevin C Maki, of Biofortis, said in a news release. "These findings add to those from prior research supporting corn oil's positive heart health benefits, and align with recommendations to replace saturated fats with unsaturated fats, such as those found in corn oil."

The study was funded in part by ACH Food Companies, Inc., which produces the corn oil product Mazola.

According to the Mayo Clinic, in the U.S., total cholesterol under 200 milligrams of cholesterol per deciliter of blood is considered desirable, while 240 milligrams per deciliter of blood is considered high. For LDL cholesterol, respectively, those values are below 70 milligrams per deciliter of blood and 160 to 189 milligrams per deciliter of blood.