An apple a day may not keep the doctor away, but it very well could help you fight off such maladies as Alzheimer’s or Parkinson’s disease, a study from Cornell University concluded recently.

According to scientists at the University, apples – especially the red ones – contain an antioxidant called quercetin. Antioxidants help your body fight substances called free radicals, which if left to themselves can lead to diseases such as cancer.

“The studies show that additional apple consumption not only may help reduce the risk of cancer, as previous studies have shown,” Chang Y. “Cy” Lee, Cornell professor, said in a statement, “but also that an apple a day may supply major bioactive compounds, which may play an important role in reducing the risk of neurodegenerative disorders” – a group of diseases that includes Alzheimer’s and Parkinson’s.

Lee’s group also found that the antioxidants in apples had a stronger effect on cancer than those found in foods with vitamin C, another source of antioxidants.

The best apples are those with red skin, and actual fresh apples are better than apple juice or applesauce, since most of the disease-fighting chemical is found in the skin.

As for the old expression, Lee said this: “Indeed, I have a reason to say an apple a day keeps the doctor away.”