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Red grapes contain several flavonoids that give them their reddish color. Flavonoids help protect against heart disease by preventing oxidation and reducing the formation of blood clots. Resveratrol, a flavonoid found in grapes, may also stimulate production of nitric oxide which helps relax muscle cells in the blood vessels to increase blood flow. These flavonoids also provide protection against cancer and prevent inflammation.
Buy grapes with red or purple skin since their anthocyanin content is higher. Freeze them to eat as a snack or to quench thirst for those on a fluid restriction for the dialysis diet.