“I love green, leafy vegetables, but need calcium. How long should I wait between eating foods with calcium and green, leafy vegetables to prevent oxalate binding of the calcium. I usually eat spinach and kale with some kind of fat, like eggs, salad dressing or other oils. Thank you!”
Adequate calcium intake is important for maintaining healthy bones. Dietary calcium can be found in a number of dairy foods, sardines, certain legumes, even oranges! But when you eat calcium-rich foods along with foods that contain oxalate, a type of antinutrient found in certain vegetables, legumes and grains, calcium bioavailability and absorption is compromised. Examples of foods high in oxalates (also called oxalic acid) are spinach, parsley, beet greens, kale, chard, peas, fava beans, navy beans, rice bran, soy flour, and wheat berries. Other common antinutrients found in greens, legumes and grains are: phytate, tannin, saponins, lectins and isoflavaones.
In order to prevent oxalate from binding to calcium is to eat foods known to contain oxalic acid 2 hours apart from dietary calcium sources. Doing this will allow enough time for the body to absorb it.
Research show that soaking green, leafy vegetables in water for at least 30 minutes, or boiling them, can significantly reduce their antinutrient content. Other methods include sprouting, and fermenting.
by Nour Amri MS, CNS
Research/ Executive Assistant
Kaplan Center for Integrative Medicine