Among the 54 healthy men and women in the feeding study, consumption of foods made with corn oil resulted in significantly lower levels of LDL (bad) cholesterol and total cholesterol than the same foods made with extra virgin olive oil. Corn oil lowered LDL cholesterol by 10.9 percent compared to extra virgin olive oil's 3.5 percent reduction1,2, and total cholesterol decreased by 8.2 percent with corn oil compared to 1.8 percent for extra virgin olive oil.2 Study participants received four tablespoons of corn oil or extra virgin olive oil in the foods provided every day, consistent with the Dietary Guidelines for Americans recommendations. All foods were provided to the study participants as part of a weight maintenance diet. The randomized, double-blind, controlled crossover clinical trial assessed the effects of dietary oils on fasting lipoprotein lipids.
The study compared the effects of corn and extra virgin olive oil on LDL cholesterol (primary outcome variable), total cholesterol, HDL cholesterol (good cholesterol), Non-HDL cholesterol, Triglycerides and the total to HDL cholesterol ratio. Study participants had fasting LDL cholesterol ≥130 mg/dL and <200 mg/dL. Fasting blood samples, along with other clinical measurements, were taken from all participants during visits to the clinical study center before and after each treatment phase of the study. "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," said Dr. Maki. "These findings add to those from prior research supporting corn oil's positive heart health benefits."
Cardiovascular disease remains the number one cause of death in the United States. Existing research supports the notion diets containing at least 5-10 percent of calories from polyunsaturated fatty acids (PUFAs) from vegetable oils, are associated with lower risk for heart disease.4
Corn oil has a unique combination of healthy fatty acids and plant sterols, which research suggests help lower cholesterol.4,5 Corn oil has four times more plant sterols than olive oil and 40 percent more than canola oil.6 Based on analysis of corn oil and 2013 USDA comparison of other cooking oils, corn oil has a plant sterols content of 135.6 mg/serving vs. 30.0 mg/serving for olive oil.7 Plant sterols are plant-based substances naturally present in fruits, vegetables, nuts, seeds, cereals, legumes and vegetable oils, such as corn oil. To the extent that plant sterols play a part in reducing blood cholesterol levels, they could have an important role in a heart healthy diet.