Oxalic Acid

Oxalic acid is a poisonous substance found in many foods, albeit in low concentration. Oxalic acid has a characteristic sour flavor best noticed in rhubarb. The concentration of oxalic acid in rhubarb leaves is so high as to make them inedible. Spinach, chard, and beet greens are also high in oxalic acid.

The oxalic acid in plants is broken down by cooking. In plants it often appears alongside potassium and calcium, and thus provokes Vata. Most acids have a sour taste, an indicator that oxalic acid provokes Pitta as well. It's chemical formula is C2O2(OH)2. Oxalic acid tends to bind with other metals such as magnesium and calcium forming a salt called an oxalate. Thus, Oxalic acid leaches these minerals from the body and are also responsible for 80% of kidney stones. Other symptoms include gout and rheumatoid arthritis.

The body readily and quickly eliminates oxalic acids. Normally healthy individuals do not need to worry about oxalic acid concentrations unless consuming a large quantity of foods containing the chemical.