Blueberries are a terrific food, and the reason they’re so terrific is because the purple color they have is a dye that contains something which has powerful antioxidant activity. The actual ingredient are called antho-cyanidins. They are pigments that help absorb free-radicals and protect the body.
But let’s talk about the other side of blueberries. If you are a person who has issues with sugar or with yeast, blueberries, especially nice fresh ones in-season can be very sweet. And they can aggravate your condition. So, they have to be chosen according to your situation. If you are overweight, or if you have excessive yeast issues, you might want to skip the blueberries. If you don’t have a problem in those arenas, and you have a lot of oxidant stress, blueberries are a terrific food, and should be eaten when they are in season.