New Research Shows Vegetable Oils Are Not Good for Heart Diseases
North Carolina's Health University School of Medicine researchers have discovered more evidence that counters the healthy practice of replacing butter and saturated fats with vegetable and corn oils.
The findings, reported in the British Medical Journal, indicate that vegetable oils high in linoleic acid might not be better than butter in terms of preventing heart disease. However, a more thorough research will have to be carried out.
Analyses from other similar tests show that using oils rich in linoleic acid failed to reduce risk of heart disease and mortality even though it reduced the cholesterol levels. In a Minnesota analysis conducted 50 years ago, the participants who had greater serum cholesterol reduction had higher risk of death, according to the New Food Magazine.
The belief that vegetable oils replacing saturated fats improve heart health dates back to the 1960s, when studies showed that these oils lowered blood cholesterol levels. Several studies have been conducted since then that suggests the same conclusion.
However, the conclusion that linoleic-acid dietary interventions can reduce the risk of heart attacks have never been shown in randomized controlled trials, which is considered the gold standard in medical research.
The Minnesota Coronary Experiment (MCE) has unpublished results with the conclusion that the intervention lowered cholesterol levels, but it made no difference in heart attack risks, deaths due to heart disease or overall deaths.
Chris Ramsden, a medical investigator, and colleagues came across the study and recovered the data, Medical Xpress reported. They performed analyses which confirmed the results of the experiment. The autopsy reports they also uncovered revealed that the corn oil group has nearly twice the number of heart attack occurrence than the control group.
They also discovered graphed summaries in the thesis of a student of one of the MCE investigators showing that patients older than 65 and women in the intervention group experienced about 15 percent more deaths than the control group during the study.
However, not all data were recovered, so it's too soon to form conclusions based on the partial data that replacement of saturated fats with corn oil is harmful to health of the heart.
The debate on why linoleic-acid rich oils could lower cholesterol levels but increases heart attack risks continues. There are some studies that suggest that these oils can cause inflammation, which is a risk factor for heart disease.