Ingredient Watch: Oxalic Acid
I have been asked a few times about oxalic acid – what is it and should we be afraid of it?
Hitting close to home, oxalic acid is found in many of our most favorite foods such as spinach, beet tops, Swiss chard, collard, and amaranth. Other foods include parsley, broccoli, turnips, almonds and cashews, green beans, quinoa, tangerines, plums, summer squash, strawberries, blueberries, blackberries, grapes, soybeans, and many more. It is even found in coffee and chocolate. I’m sure this group (myself included) is split between which is more alarming – the connection with coffee and chocolate or the green matter, the cornerstone of good health.
What is it? Oxalic acid is a strong acid found in both animal and plant life. An oxalate is the salt crystal of oxalic acid. The salt occurs when the acid forms a strong bond with minerals including sodium, calcium, potassium and magnesium. Many believe that this bond is what causes the vast majority of kidney stones. However, not everyone holds the belief that this comes from foods high in oxalic acid.
“About 85% of all kidney stones contain calcium salts, calcium oxalate and/or calcium phosphate. It seems logical to connect calcium oxalate with oxalic acid in some foods, such as spinach, soy, tea, coffee, wheat, and some others. However, you will not find any scientifically documented evidence that oxalic acid in food causes the formation of kidney stones.” http://rawfamily.com/news
In an article published in the journal “Urologic Nursing” in 2007, registered dietitian Laura R. Flagg concluded that the data on oxalate foods actually causing kidney stones is “insufficient” and discouraged the limiting of these foods for patients with stones. http://healthyeating.sfgate.com/oxalic-acid-foods-8447.html
An article in the NY Times recommends an increase in water and a decrease in protein and sodium to avoid stones. Drinking throughout the day, keeping your urine watery and pale yellow or clear is indicative that you’re getting enough water. On oxalate-rich foods, they say “Most people with calcium oxalate stones should not avoid oxalate-rich foods unless the doctor specifically recommends a restrictive diet. Oxalate binds with calcium in the intestine, which may actually reduce calcium absorption. Some studies, in fact, indicate that eating foods containing oxalates and calcium together may reduce the risk of stones. Most of the foods that contain oxalates are very important for good health. Limiting oxalates may be particularly harmful in people with bowel disorders in which there is malabsorption.” http://www.nytimes.com/health/guides/disease/kidney-stones/prevention.html
Oxalic acid generally increases as foods mature, producing increasingly bitter vegetables. Young, fresh vegetables such as baby spinach are less likely to have oxalic acid. Even younger leaves can taste bitter, however. Many believe that this is a sign that your body has had enough. Listen to what your body tells you. Eat what you like and as much as feels good to eat. Other than on advice from your doctor, when your stomach (nausea) or mouth (taste) tells you to stop, do so. Your body is incredibly smart. You just need to listen. ~Lorrie