Oxalates are a salt of oxalic acid and a mineral, such as potassium or magnesium. Oxalic Acid (from the diet or that is produced in the body) binds to minerals and metals if it comes into contact with them, and then tends to precipitate out and settle into the tissues. Some oxalates, such as those including magnesium, are much more water soluble (and thus more likely to be excreted) than others, such as calcium oxalate or mercury oxalate. Oxalic Acid has a particular affinity for mercury and there is reason to believe that the level of oxalic acid in a person's body at the time of exposure to mercury is one factor determining how much mercury will be retained in the body and lead to poisoning. Many vaccine-injured children were taking antibiotics at the time of vaccination, and maybe this explains the connection, as they likely had elevated yeast levels at that time due to the antibiotics (and yeast produces oxalate). The formation of calcium oxalate crystals also lowers the amount of calcium available for use in the body, which then leads to problems associated with low calcium levels such as problems with the nervous system, elevated histamine levels, difficulty keeping yeast in the body under control, and problems with bones and teeth.
There are a number of sources of oxalates. Some oxalate is made in our bodies, converted from substances such as vitamin C. According to Wikipedia, the incomplete breakdown of carbohydrates can result in oxalates. Wikipedia also cites research showing that metabolism of ethylene glycol (antifreeze) can result in oxalates. While it is unlikely that you intentionally ingest antifreeze or give it to your child, it is a component of a surprising number of pharmaceuticals including vaccines and some laxatives. Polyethylene glycol is an even more common additive, and I don’t know if it is metabolized the same way. Deficiencies of several vitamins, including B6 and K2, can lead to overproduction of oxalate in the body. For people with serious oxalate sensitivity, this may be the source of most of the oxalate.
According to Susan Owens, who has pioneered research into oxalates and the low oxalate diet, the body produces excess oxalates when there is a deficiency of vitamin B6. Because this is one of the primary features of Pyrroluria, it may make sense to test people sensitive to oxalates for this condition. This is done with a $40 urine test so it is an easy test to do. Many people have noticed that supplementing with B6 helps reduce the effects of oxalates, and can even lead to “oxalate dumping” which is essentially a temporary worsening of symptoms from detoxing oxalates quickly.
In addition to reducing oxalate intake, there are other things that can be done to help. Taking calcium citrate before meals helps by binding with the oxalic acid in the food, thereby keeping the oxalate crystals in the GI tract so that they can be excreted rather than being absorbed into the bloodstream. Wikipedia cites research showing that this protocol can reduce uptake of oxalates by the body by as much as 97% in rats. Supposedly, taking probiotics is one of the most powerful things that can be done. There are good bacteria which are able to absorb and neutralize oxalates, which might be why many people do not seem to be hurt by them. Specifically, the probiotic Bifidus Infantis is supposed to be helpful (and possibly all of the Bifido bacteria), and the prescription probiotics VSL #3 is also supposed to be very effective. Magnesium can help the body rid itself of oxalate, and the amino acid arginine can reduce the symptoms associated with oxalate dumping, such as pain.
There are quite a few lists online of high oxalate foods, and they tend not to agree. This is at least partly due to the fact that previous testing methods have not been very accurate, and lists that include old, outdated measurements have not been taken down or updated. This also occurs because oxalate level can vary between different varieties of the same food, such as green beans, and can also vary depending on which part of the plant was tested and how ripe it was. For the most updated list of food oxalate status, join the yahoo group Trying_Low_Oxalates and check in the files section.
Cooking has an inconsistent impact on the oxalate level of a food. Some foods, such as carrots and kale, have lower levels once they have been boiled (and the water used for boiling discarded). Other foods, such as spinach and chard, actually have more available oxalate after they are cooked. Soaking and then drying nuts and seeds according to the method for Crispy Nuts in the cookbook Nourishing Tradition is supposed to lower their oxalate content, although the best estimate I have for how much is 3%. Since the effect of cooking has such a varied effect on oxalate4 level, this technique may also reduce the oxalate level of some nuts and seeds more than others. More research needs to be done to establish this. To do this, soak the nuts or seeds in fresh water to cover for 7-12 hours (most people just leave them overnight) then dry either in a dehydrator or in an oven set to its lowest temperature. This may take between 4 and 48 hours depending on the size of the nuts or seeds.
It has been discovered that oxalates are central to a group of disorders involving genital pain. The website for the Vulvar Pain Foundation is a wealth of information about oxalates and what to do about them:
More info about oxalates from this site:
This group has a Low Oxalate Cookbook (version 2 is more updated):
The following link is to a paper by Susan Owens about oxalates, how they impact the gut, and how a low oxalate diet may help people with autism:
From this site “Scientists have found our bodies make excess oxalate when deficient in vitamin B6, which is a vitamin that has been under a lot of study in autism. Some people may make excess oxalate from an excess of glycine.” I will include more about how oxalates may relate specifically to autism spectrum disorders, including more on the work of Susan Owens, in a future post.