Both Acai berries and dark cherries are powerful antioxidants with acai at the top of the ORAC scale (oxygen radical absorbance capacity) which the USDA scientists have developed a way to measure the ability of antioxidants to absorb free radicals. (USDA Human Nutrition Research Center at Tufts University) Free radicals are an atom or group of atoms with one or more unpaired electrons especially one that is produced in the body by natural biological processes or introduced from an outside source and that can damage cells, proteins, and DNA by altering their chemical structure. Essentially they are unstable molecules, atoms or ions that can cause harm to the body. (www.merriam-webster.com/dictionary/freeradical)