What is tartaric acid and what is known about this product? A toxicology manual indicates that tartaric acid is a highly toxic substance. As little as 12g has caused human fatality with death occurring from 12 hours to 9 days after ingestion. Gastrointestinal symptoms were marked and followed by cardiovascular collapse and/or acute renal failure. A gram is approximately the weight of a cigarette. This compound especially damages the muscles and the kidney and may even cause fatal human nephropathy which was of interest to me since the two brothers with autism initially evaluated had the extreme muscle weakness as well as evidence of impaired renal function.
Interestingly, tartaric acid is also elevated in urine samples of adults with the disorder fibromyalgia, a debilitating disease associated with muscle and joint pain, depression, foggy thinking, and chronic fatigue. Values for tartaric acid in urine may be extremely elevated in autism. A young Korean child with autism had a value of 6000 mmol/mol creatinine, a value that is about 600 times the median normal value. Assuming that the yeast in the intestine of the child were producing tartaric acid at a constant rate, this child would be exposed to 4.5 grams per day of tartaric acid, over one-third of the reported lethal dose of tartaric acid! Proponents of the theory that wheat gluten sensitivity is the main biochemical abnormality in autism would have difficulty in explaining this case since rice was the only grain in this child's diet.
Surprisingly, the Food and Dr.ug Administration lists tartaric acid in the Generally Recognized As Safe or GRAS category which means this product can be freely used as an additive in processed foods. Unless a food additive is put on the GRAS list, the food company using the product may have to spend thousands or even millions of dollars to prove its safety. Therefore, the political pressure to get a product on this GRAS list is intense. Tartaric acid is a byproduct of the wine industry since a tremendous amount of tartaric acid sludge has to be removed from the wine after yeast fermentation of the grape juice. This sludge is the primary source of tartaric acid used as a food additive.
Tartaric acid has not yet been found in Candida culture media. It may actually be due to plain baker's yeast rather than Candida. Tartaric acid may only be formed in the absence of oxygen. It is also available as a food additive in baking powder, grape and lime flavored beverages, and poultry. It may also be found in grapes and grape products. Cream of tartar which may be used for baking is nearly pure tartaric acid. Its purposes in the food industry include firming agent, flavor enhancer, flavoring agent, humectant, acidity control agent, and sequestant. There is no evidence that any mammals can produce it, so it is probably purely a yeast by-product. Tartaric acid is an analog of the Krebs cycle compound malic acid. An analog is a chemical compound that closely resembles but is not identical to another chemical compound. The atoms that differ in the two molecules are shaded in gray. The reason an analog is important is that the analog may prevent the normal biochemical from completing its normal biochemical function.