Foods high in oxalic acid include vegetables from the quinoa family, umbelliferae family, amaranth family, and amaranth family. In general, you can judge the level of oxalic acid by the astringent flavor of the food. If a vegetable has a strong astringent flavor, it may contain more oxalic acid. And proper processing and cooking can reduce the oxalic acid in vegetables to a level that is not hazardous to health. 1. Quinoa family: the representative vegetables are spinach (0.97g/100g), beet leaves (0.61g/100g), thick-skinned vegetables (0.41g/100g) and so on. 2. Umbelliferae: the representative vegetables are celery (1.7g/100g), carrot (0.5g/100g) and so on. 3. Amaranthaceae: the representative vegetables are amaranth (1.09g/100g) and so on. 4. Amaranthaceae: the representative vegetables are amaranth (1.31g/100g) and so on. In addition, the content of oxalic acid in fresh bamboo shoots, bitter melon and wild rice is also high, which is an important reason for their astringent flavor. There are also many vegetables, such as watercress, eggplant, leek, garlic, and broccoli, that have relatively high oxalic acid content, ranging from 0.2% to 0.5%. In contrast, vegetables from the cruciferous family, such as Chinese cabbage, bok choy, cabbage, and kale, have very low levels of oxalic acid, below 0.1%. Tomatoes, cucumbers, pumpkins, and potatoes are also low oxalate vegetables.