Some Vegetable Oils Labeled as 'Healthy' Replace Saturated Animal Fats with Polyunsaturated

Despite what labels and nutritional facts may say, some vegetable oils that claim to be healthy may actually increase the risk of heart disease.

Replacing saturated animal fats with polyunsaturated vegetable oils has become very common today as this can misleadingly reduced serum cholesterol levels and help prevent heart disease.

"Careful evaluation of recent evidence, however, suggests that allowing a health claim for vegetable oils rich in omega-6 linoleic acid but relatively poor in omega-3 α-linolenic acid may not be warranted," Drs. Richard Bazinet, Department of Nutritional Sciences, University of Toronto and Michael Chu, Lawson Health Research Institute and Division of Cardiac Surgery, Western University, London, Ontario notes, via a press release.

"Corn and safflower oil, which are rich in omega-6 linoleic acid but contain almost no omega-3 α-linolenic acid, are not associated with beneficial effects on heart health according to recent evidence. The authors cite a study published earlier this year in February 2013 "... in which the intervention group replaced saturated fat with sources of safflower oil or safflower oil margarine (rich in omega-6 linoleic acid but low in omega-3 α-linoleic acid).

Background information from the study shows that the intervention group had serum cholesterol levels that were significantly decreased relative to baseline and the control group, which is consistent with the health claim.

The study notes the following, via the release: "In Canada, omega-6 linoleic acid is found in corn and safflower oils as well as foods such as mayonnaise, margarine, chips and nuts. Canola and soybean oils, which contain both linoleic and α-linolenic acids, are the most common forms of oil in the Canadian diet. "... it is unclear whether oils rich in omega-6 linoleic acid but low in omega-3 α-linolenic acid also reduce this risk. We suggest that the health claim be modified such that foods rich in omega-6 linoleic acid but poor in omega-3 α-linolenic acid be excluded," conclude the authors."

More information regarding the study can be found via the Canadian Medical Association Journal.