Results of a new study may encourage many Americans to increase their intake of some different fruits and vegetables to maximize their phytonutrient intake and decrease the risk for certain chronic diseases, including cardiovascular disease, cancer and diabetes.

Researchers found that despite the availability of a wide range of foods that contain phytonutrients, many Americans are getting them from a relatively small number of specific foods, which are not necessarily the most concentrated sources.

Phytonutrients are compounds that naturally occur in plants and provide a range of potential health benefits from promoting eye, bone and heart health to supporting immune and brain function. It’s widely believed that the health benefits that phytonutrients may offer come from the pigments in fruits and vegetables that give these foods their vibrant reds, yellows, greens and other rich colors.

"Americans could improve their phytonutrient intake by choosing to eat more concentrated sources of phytonutrients as well as a wider variety," said researcher Dr. Keith Randolph. "For example, grapes are the top contributor of the phytonutrient family of anthocyanidins in most Americans’ diets, but blueberries actually contain higher amounts of this phytonutrient.

The most common phytonutrient sources include oranges, orange juice, carrots, grapes, garlic, tomatoes, strawberries, prepared mustard, tea and various soy products, according to researchers. However, sweet potatoes, papaya, kale, raspberries and watercress all offer higher amounts of these beneficial nutrients.