A recent study at the University of Illinois has re-confirmed a very famous saying "An apple a day keeps doctor away" by concluding that soluble-fiber rich foods like oats, apples, and nuts not only help in lessening inflammation that leads to obesity, but also are capable of strengthening the immune system. It was found that the soluble fiber products produce interleukin-4, which is an anti-inflammatory protein.

Elaborating on the study, Gregory Freund, a Professor in the University of Illinois' College of Medicine said, "Soluble fiber changes the personality of immune cells, they go from being pro-inflammatory, angry cells to anti-inflammatory, healing cells that help us recover faster from infection".

In this study, laboratory mice were experimented as they were made to consume identical low-fat diets with soluble or insoluble fibers for six weeks. This study is expected to be published in the May 2010 issue of Brain, Behavior, and Immunity.