QUESTION: Should I avoid eating spinach because it has oxalic acid?
VICTORIA: The oxalic acid in food is considered harmful because it can combine with calcium and may leach the body of this important mineral. For some reason everyone knows of the oxalic acid in spinach, but is not aware of the oxalic acid content in many other commonly eaten foods such as grains, beans, and especially coffee and tea. While spinach is loaded with calcium which minimizes the loss of this mineral from your body, coffee has none. I would be more concerned about the oxalic acid content in coffee and other products than in spinach. At the same time, even though the oxalic acid content in spinach is minute, if you do not rotate your greens and use only spinach for many weeks, you may accumulate oxalic acid and experience symptoms of poisoning. Remember, rotate your greens!