High Oxalate: A Major Factor in Tissue and Blood Vessel Health

OXALATE METABOLISM 

Oxalate (and its acid form, oxalic acid), is an organic acid that is primarily derived from three sources: the diet, fungus (such as Aspergillus and Penicillium), possibly Candida, and also human metabolism. Oxalic acid is the most acidic organic acid in body fluids and is used commercially to remove rust from car radiators. Antifreeze (ethylene glycol) is toxic primarily because it is converted to oxalate in the body. Two different types of genetic diseases are known in which oxalates are high in the urine, hyperoxalurias type I and type II, which can also be determined from the Organic Acids Test.  

In the genetic disease hyperoxaluria type I and in vitamin B-6 deficiency, there is a deficiency in the enzyme activity of alanine glyoxylate amino transferase (AGT), leading to the accumulation of glyoxylic acid. The high glyoxylic acid can then be converted to glycolate by the enzyme GRHPR or to oxalate by the enzyme LDH. Thus, glycolate, glyoxylate, and oxalate are the metabolites that are then elevated in the Organic Acids Test in hyperoxaluria type I and in vitamin B-6 deficiency.  

In the genetic disease hyperoxaluria type II, there is a deficiency in an enzyme (GRHPR) that has two biochemical activities: glyoxylate reductase and hydroxypyruvic reductase. This enzyme converts glyoxylate to glycolate and glycerate to hydroxypyruvate. When this enzyme is deficient, glycerate cannot be converted to hydroxypyruvate and glyoxylate cannot be converted to glycolate. In this disease, glyoxylate is increasingly converted to oxalate and glycerate is also very elevated. 

External sources of oxalates include ethylene glycol, the main component of antifreeze. Antifreeze is toxic mainly because of the oxalates formed from it. In addition, some foods also contain small amounts of ethylene glycol. Vitamin C (ascorbic acid or ascorbate) can be converted to oxalates but apparently the biochemical conversion system is saturated at low levels of vitamin C so that no additional oxalate is formed until very large doses (greater than 4 grams per day) are consumed. The deposition of oxalates in critical tissues such as brain and blood vessels, the oxidative damage caused by oxalate salts, and the deposition of oxalate mercury complexes in the tissues. 

HOW CAN HIGH OXALATES BE TREATED? 

Implement a low-oxalate diet. This may be especially important if the individual has had Candida for long periods of time and there is high tissue oxalate buildup.  

• Use antifungal drugs to reduce yeast and fungi that may be causing high oxalates. Children with Autism Spectrum Disorders frequently require years of antifungal treatment. Arabinose, a marker used for years for yeast/fungal overgrowth in the Organic Acids Test is correlated with high amounts of oxalates.  
• Supplements of calcium and magnesium citrate can reduce oxalate absorption from the intestine. Citrate is the preferred calcium form to reduce oxalate because citrate also inhibits oxalate absorption from the intestinal tract.  
• N-Acetyl glucosamine supplements can stimulate the production of the intercellular cement, hyaluronic acid, to reduce pain caused by oxalates.  
• Chondroitin sulfate can prevent the formation of calcium oxalate crystals.  
• Vitamin B6 is a cofactor for one of the enzymes that degrades oxalate in the body and has been shown to reduce oxalate production.  
• Excessive fats in the diet may cause elevated oxalates if the fatty acids are poorly absorbed because of bile salt deficiency. If taurine is low, supplementation with taurine may help stimulate bile salt production (taurocholic acid), leading to better fatty acid absorption and diminished oxalate absorption.  
• Probiotics may be very helpful in degrading oxalates in the intestine. Individuals with low amounts of oxalate-degrading bacteria are much more susceptible to kidney stones. Both Lactobacillus acidophilus and Bifidobacterium lactis have enzymes that degrade oxalates.  
• Increase intake of essential omega-3 fatty acids, commonly found in fish oil and cod liver oil, which reduces oxalate problems. High amounts of the omega-6 fatty acid, arachidonic acid, are associated with increased oxalate problems. Meat from grain fed animals is high in arachidonic acid.  
• Supplements of vitamin E, selenium, and arginine have been shown to reduce oxalate damage.  
• Increase water intake to help eliminate oxalates.

HIGH OXALATE FOOD LIST