America's blueberry and its European cousin the bilberry (often made into jam) get their deep blue hue from antioxidants called anthocyanins.
Several studies suggest anthocyanins may enhance heart health by improving cholesterol levels and blood sugar metabolism, as well as fight oxidative stress. In a 2008 study from the Journal of Agricultural and Food Chemistry, preliminary research suggested that anthocyanins may protect against obesity. The growth of breast cancer cells were also inhibited by anthocyanins, in a 2010 laboratory study published in Phytotherapy Research.
The US Department of Agriculture's Center for Aging at Tuft's University studied more than 40 fruits and vegetables and discovered that blueberries had the highest levels of antioxidants of all the fruits and vegetables studied.
Summer fruits like peaches and nectarines have been found to contain phytochemicals (chemical compounds produced by plants) that are important for a healthy body. Phytochemicals are being studied as prevention and treatment for many health conditions, including cancer, heart disease, diabetes, and high blood pressure. Some of the links between individual phytochemicals and cancer risk found in laboratory studies are compelling and make a strong case for further research.
Phytochemicals found in peaches and nectarines also act as an antioxidant. These types of antioxidants are thought to rid the body of harmful molecules known as free radicals, which can damage a cell's DNA and may trigger some forms of cancer, increased aging, and other diseases.