WASHINGTON, Dec. 20, 2017 /PRNewswire-USNewswire/ -- Independent scientists assure consumers that they can "forget" about misleading reports originating from a Dec. 7 study on canola oil and Alzheimer's disease by Temple University researchers as the data do not support negative claims about the oil. The links between canola oil and weight gain, worsened memory and dementia in humans suggested by this 22-mouse study are unfounded, notes the nonprofit U.S. Canola Association. Here's why:
- The study was conducted in mice; it was not a human clinical trial. There is no causal link to Alzheimer's disease in people. In fact, mouse models for degenerative disease are not directly relevant to humans.
- The canola oil-fed mice gained weight because they were consuming more calories than the control mice. The two diets were not balanced for fat content. A previous study by the same group with olive oil showed comparable weight gain.
- Out of six measures and three different tests, the canola oil-fed mice were different for only one test and showed just a slight difference in behavior when mice walked to a fork in a road and decided which direction to take. Rodents like to explore new space, so the tendency is to alternate between both directions in the maze. The 10 mice that ate canola oil didn't alternate as much as the 12 non-oil eaters. This does not equate to "significant deficits of working memory."
"This mouse model is a huge stretch from what you may see in humans," says Peter J. Jones, Ph.D., Canada research chair in functional foods and nutrition, Richardson Center for Functional Foods and Nutraceuticals, University of Manitoba.
"The paper does not show in any way that there is a causal link to disease in humans. Not even close," echoes Kevin Folta, Ph.D., chair of the Horticultural Science Department at the University of Florida, in his critique of the study "No Evidence of Canola Oil Causing Alzheimer's and Dementia."
"Animal models of Alzheimer's lack predictive validity," adds Richard Bazinet, Ph.D., associate professor at the University of Toronto's Department of Nutritional Science, who specializes in the regulation and role of dietary fat metabolism in neurodegenerative diseases. "We have a series of major phase III clinical trials in Alzheimer's disease. The drugs 'worked' in the animal models, but failed in humans."
Moreover, the two diets in the Temple University study were not balanced for fat content, notes Jones.
"We know that higher fat diets are more palatable and lead to increased food intake and weight gain, which is what happened here," he explains. "This weight gain would have happened with any type of fat being provided. Animals with greater body fat will elicit reduced food-seeking behavior which may, independent of any fat-induced action, well explain the differences in brain chemistry and memory."
"The notion that canola oil is linked to dementia and worsens Alzheimer's symptoms in no way reflects what the data present," adds Folta. "These results do not indicate any ill effect on human health."
Finally, the Temple University research mistakenly compared the results of canola oil to olive oil when the latter was not even included in the study. The health benefits of canola oil overall were also erroneously called into question.
"The contrast in the study of canola oil with olive oil is completely inappropriate without a group fed olive oil being tested," says Jones. "This is an absurd over-reach of what the data provide without testing both oils side by side."
Human clinical trials with canola oil have been going on for decades involving thousands of volunteers to examine its effects on the body. A scientific literature review, published in the peer-reviewed journal Nutrition Reviews in May 2013, summarized 40 research studies related to the health benefits of canola oil. In 2006, the U.S. Food and Drug Administration authorized a qualified health claim about canola oil's ability to reduce the risk of heart disease when used in place of saturated fat.
"The health benefits of canola oil are well known and scientifically proven," notes USCA President Rob Rynning, canola grower in Minnesota. "That's why health experts recommend that people cook with canola oil."
For more information about canola oil, go to www.uscanola.com.
SOURCE U.S. Canola Association