Study Suggests Choosing Tart Cherries May Help Reduce Risk Factors for Type 2 Diabetes

31/10/07 For the more than 50 million Americans who have "pre-diabetes" (also known as metabolic syndrome), a cluster of health factors that put them at risk for type 2 diabetes, eating tart cherries may have a whole new meaning.

A recent study in animals by University of Michigan researchers found diets enriched with antioxidant-rich cherries significantly lowered insulin and fasting glucose levels, key markers for the development of type 2 diabetes. Adding cherries to the diet also lowered the animals' total cholesterol levels and triglycerides after 90 days.

The American Diabetes Association estimates that most Americans with pre-diabetes will develop type 2 diabetes within 10 years unless they make changes to their food and exercise behaviors. More than 20 million Americans already have type 2 diabetes, a condition that greatly increases the risk for other diseases including heart disease and stroke.

"Cherries are packed with powerful plant pigments called anthocyanins -- which give cherries their dark red color -- and it's these compounds we believe lower blood sugar and insulin levels," said study co-author Dr. Steven F. Bolling, a cardiac surgeon at the University of Michigan Cardiovascular Center who also heads the U-M Cardioprotection Research Laboratory, where the study was performed in laboratory rats. "We are encouraged to see in these animal trials that cherries have the potential to help reduce the risk for serious conditions like metabolic syndrome, or 'pre-diabetes,' and it certainly warrants additional clinical research in humans."

The study also showed the cherry-fed groups had lower levels of a plasma marker of oxidative damage and increased blood antioxidant capacity -- not surprising since cherries are one of the richest sources of antioxidants.

The study used whole tart cherries in powder form, which was fed to rats as one percent of their total diet.

While the amount of cherries used in the study could equate to reasonable amounts in a human diet, humans and rats differ substantially in the ability to absorb nutrients like anthocyanins and more research is needed to translate this science into a diet recommendation.

More than 60 studies have linked tart cherries, the kind consumed as dried, frozen or juice, to a variety of potential health benefits including helping to ease arthritis pain to reducing risk factors for heart disease and some cancers. You can find out more details about the benefits of tart cherries by visiting http://www.choosecherries.com. There you will find the Cherry Nutrition Report as well as ways to enjoy cherries year-round.

The study on cherries was presented at the scientific conference Experimental Biology and has been submitted for publication in a medical journal. The study was funded by the Cherry Marketing Institute, which provided an unrestricted grant to the University of Michigan to conduct the research and was not directly involved in the design, conduct or analysis of the project.

Cherry-enriched diets reduce metabolic syndrome and oxidative stress in lean Dahl-SS rats. Experimental Biology 2007 225.8, Seymour EM, Singer AAM, Bennink MR, Bolling SF.  Presented in minisymposium 225, Dietary Bioactive Compounds: Chronic Disease Risk Reduction.