23 Mar 2010 --- Long known for being an excellent source of fiber, two recent studies suggest that apples might be the key to achieving a healthy immune system and better gut health. Rich in antioxidants, previous research has suggested that apples may prevent or reduce the risks of certain types of cancer and heart disease as well as improve cognition and memory. This new research adds to the ongoing list of reasons why you should enjoy an apple (or two) a day!

One study, performed by researchers at the University of Illinois at Urbana-Champaign, suggests that the soluble fiber found in apples reduces inflammation associated with obesity-related diseases and builds up the immune system. According to the researchers, soluble fiber may alter the characteristics of immune cells to speed up recovery from infection.

In this animal study, laboratory mice that consumed soluble fiber had positive changes in their immune systems after only six weeks of treatment. They also recovered 50 percent sooner from sickness than the control group. The study will appear in the May 2010 issue of Brain, Behavior, and Immunity.

A second study concludes that apples may also promote growth of "friendly bacteria" that helps keep the gut healthy, which also strengthens the immune system. Researchers at the Technical University of Denmark's National Food Institute found that long-term consumption of whole apples had a positive impact on the intestinal flora in the rat subjects tested. The findings point to the the apple pectin - a type of dietary fiber found in apples - as the main reason for this, however they note it's likely the pectin works in tandem with the abundance of polyphenols found in the apple.

Among the effects noted by researchers, consumption of apples appeared to increase activity of butyrate- and beta-glucuronidase two-fold, as compared to control animals. These bacteria help to improve overall intestinal health and may reduce the risks of related cancer. According to the research, published in January by BMC Microbiology, this study showed for the first time the effects of apple consumption on the intestinal microbial population.

Both ground-breaking studies open the door to future trials to determine whether apples have the same impact on the human immune and digestive systems as they do on the animals in these studies.

As National Nutrition Month comes to an end, it is the perfect time to start focusing on healthful eating. Small changes, like including more apples and apple products into your diet, can help you keep your focus on healthful eating for disease prevention.