They require excessive filtration and re-circulation within your bloodstream.
You may think food dyes are easy to spot, but they can be found in so many grocery products, including:
-Baked goods
-Candy
-Pie filling
-Cake frosting
-Cake mix
-Fruit snacks
-Cereals
-Sodas
To avoid them, always check the ingredients when purchasing processed foods. And better yet, avoid processed foods whenever you can!