Chang Y. Lee of Cornell University in Ithaca, N.Y., said apples, bananas and oranges are the most common fruits in Western and Asian diets and are important sources of vitamins, minerals and fiber.

The Cornell University researchers investigated the effects of apple, banana and orange extracts on neuron cells and found that the phenolic phytochemicals of the fruits prevented neurotoxicity on the cells.

The study, published in the Journal of Food Science, said among the three fruits, apples contained the highest content of protective antioxidants, followed by bananas and then oranges.

The study demonstrated that antioxidants in the major fresh fruits consumed in the United States protected neuronal cells from oxidative stress," the authors said in a statement. "Additional consumption of fresh fruits such as apples, bananas and oranges may be beneficial to improve effects in neurodegenerative diseases such as Alzheimer's."