After observing the animals for 12 months, they weighed them. They found that the mice on the canola oil diet weighed significantly more than those on a regular diet.
They then assessed their working memory, short-term memory and learning ability by administering maze tests. They discovered the mice that had consumed canola oil suffered damage to their working memory. The canola oil-treated mice had reduced levels of amyloid beta 1-40, a protein that serves as a beneficial role in the brain.
“As a result of decreased amyloid beta 1-40, animals on the canola oil diet further showed increased formation of amyloid plaques in the brain, with neurons engulfed in amyloid beta 1-42,” the authors said. “The damage was accompanied by a significant decrease in the number of contacts between neurons, indicative of extensive synapse injury. Synapses, the areas where neurons come into contact with one another, play a central role in memory formation and retrieval.”
Their findings suggest canola oil is not beneficial to the brain, especially when it is consumed over long periods of time. Researchers now hope to further their studies to find out exactly how much canola oil can produce changes in the brain and if it can be linked to Alzheimer’s disease.
“Even though canola oil is a vegetable oil, we need to be careful before we say that it is healthy,” lead researcher Domenico Pratico. “Based on the evidence from this study, canola oil should not be thought of as being equivalent to oils with proven health benefits.”