A mouse study has found that canola oil in the diet was associated with worsened memory, worsened learning ability, and weight gain in Alzheimer's mice.
Canola oil-treated animals also had greatly reduced levels of amyloid beta 1-40 (the “good” version), leading to more amyloid-beta plaques (made from amyloid beta 1-42), and a significant decrease in synapses.
The mice were given the equivalent of about two tablespoons of canola oil daily. The mice began their enriched diet at 6 months of age, before they developed any signs of Alzheimer's.
A previous study by the same researchers found that Alzheimer’s mice fed a diet enriched with extra-virgin olive oil had reduced levels of amyloid plaques and phosphorylated tau and experienced memory improvement.
Moreover, olive oil reduced inflammation in the brain, improved synaptic integrity, and dramatically increased levels of autophagy (the process by which waste products from cells are cleared away).
(2017). Effect of canola oil consumption on memory, synapse and neuropathology in the triple transgenic mouse model of Alzheimer’s disease.
Scientific Reports. 7(1), 1 - 9.
(2017). Extra-virgin olive oil ameliorates cognition and neuropathology of the 3xTg mice: role of autophagy.
Annals of Clinical and Translational Neurology. 4(8), 564 - 574.