Foods High in Oxalates | Spinach, kale, nuts, cocoa, and seeds, these superfoods are very popular among those who are health conscious. However are these health foods causing more problems than you think? One person’s superfood may be another person’s poison. Leafy greens, fruits, vegetables, seeds, and nuts are known to have an organic compound called oxalic acid, or oxalates. One of the major concerns regarding oxalic acid is that it can bind to certain minerals in the gut and prevent mineral absorption. Diets high in oxalates have been linked to increased risk of kidney stones and other health problems.
What is oxalic acid?
Found organically in many plants, oxalates can also be produced by your body or obtained from foods. Vitamin C can also be converted to oxalic acid when it is metabolized. When oxalates are consumed, they bind to minerals such as calcium oxalate and iron oxalate in the colon. For most individuals these mineral compounds are excreted through the stool or urine. However, for some individuals high-oxalate diets have been shown to cause health issues and interfere with absorption of important minerals leading to nutrient deficiencies.
Oxalates tend to bind with minerals when eaten with fiber. For example, spinach contains high amounts of calcium. However spinach also contains high amounts of oxalates, which prevents majority of the calcium from being absorbed by the body. According to the American Journal of Clinical Nutrition (https://www.ncbi.nlm.nih.gov/pubmed/6305185), eating foods that are high in fiber and oxalates may further inhibit nutrient absorption. While only some minerals bind to oxalates, it is important to be aware of the amount of oxalic acid you are getting in your diet, especially if you have a history of nutrient deficiencies.
Health concerns regarding oxalic acid
The main health concern regarding a high oxalic acid diet is the increased risk of developing kidney stones. It is normal to find calcium along with oxalates in the urinary tract, however when these compounds do not dissolve or when they bind to crystals, stones can form. If oxalates are elevated and you are dehydrated, the likelihood of developing kidney stones is high.
Individuals who have a history of kidney stones are advised to keep a low oxalate diet to prevent oxalate overload. The amount oxalic acid in your diet is an individualized matter and should be based on your urinary levels.
What foods are high in oxalates?
Majority of the foods that are high in oxalates are also very healthy. So should you restrict yourself from your leafy greens? The answer is no, of course not! However, it is important to be aware of the foods are especially high in oxalic acid.
The following is a list of foods that are high in oxalates:
- Cocoa powder
- Swiss chard
- Sweet potatoes
- Star fruit
Boiling foods that are high in oxalates prior to eating them will greatly reduce its oxalate content. Drinking lots of water and staying hydrated will also help prevent the formation of kidney stones.
If you have a history of kidney stones or you are concerned about a high oxalate diet, consider a consult with a doctor of natural medicine Overland Park, KS, who can assist you. As a specialist in functional medicine, the best treatment plan will be created to help your symptoms and improve your overall health.
Thanks to LifeWorks Integrative Health, for their insights about oxalate overload, as well as alternative medicine.