Temple University research shows extra-virgin olive oil protects against memory loss, preserves the ability to learn and reduces conditions associated with Alzheimer's disease.
Researchers at the college's Lewis Katz School of Medicine found mice with EVOO-enriched diets had better memories and learning abilities compared to the rodents who didn't eat the oil.
The real effect of EVOO appeared in the inner-workings of the mice's brains. Neuron connections in the brain were better preserved in those on an EVOO diet.
Also, olive oil reduces brain inflammation and activates the autophagy process, whereby intracellular debris and toxins are removed. Such debris and toxins are firm markers of Alzheimer's disease. A reduction in autophagy, researchers claim, is suspected to be the beginning of Alzheimer's disease.
Olive oil is the cornerstone of the Mediterranean diet, which is praised for its various health benefits. This study, which was published Wednesday in the Annals of Clinical and Translational Neurology, adds to that previous research.
"The thinking is that extra-virgin olive oil is better than fruits and vegetables alone," said senior investigator Domenico Pratico, a professor at the Lewis Klein School of Medicine. "As a monounsaturated vegetable fat, it is healthier than saturated animal fats."
The two groups of mice didn't differ in appearance after months on their respective diets. The mice were tested at 9 and 12 months with those on an EVOO diet testing better on working and spatial memory and learning abilities.
Alzheimer's disease is the most common form of dementia in the United States and affects a person's thought, memory and language. The U.S. Centers for Disease Control and Prevention said the disease typically starts after age 60 with mild memory loss. There is no cure.
Alzheimer's cases are on the rise. In 2013, 5 million Americans had the disease. That number is expected to triple to 14 million by 2050.
Pratico said the "exciting" finding sets researchers up for another experiment. The next step is to introduce EVOO later in the aging process.
"Thanks to the autophagy activation, memory and synaptic integrity were preserved, and the pathological effects in animals otherwise destined to develop Alzheimer's disease were significantly reduced," Pratico said. "We want to know whether olive oil added at a later time point in the diet can stop or reverse the disease."