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Fibromyalgia & Chronic Fatigue

Yeast Byproducts in Fibromyalgia Patients

According to William Crook, MD, the author of twelve books and numerous medical articles, "CFS/CFIDS and FMS are often yeast-related.…Increasing evidence shows that a sugar-free special diet and antifungal medications may help people with these chronic disorders get well." (1).

At The Great Plains Laboratory, some of the reasons that yeast overgrowth causes so many problems are becoming clear. We have found that patients with fibromyalgia have abnormally high levels of yeast and fungal metabolites in the urine. One of the most prevalent of these yeast or fungal metabolites is called tartaric acid. We have found that this compound can be elevated as high as 50 times normal in adults with fibromyalgia.

Click here to view the Recommendations By Disorder Chart (PDF)

Tartaric Acid

Tartaric acid is a muscle toxin. When administered to experimental animal, tartaric acid causes muscle damage. In fact, as little as 12 grams have been fatal to a human (3). (One gram is about the weight of a cigarette.)

The main natural source of tartaric acid is yeast (2). The process in the body is similar to the wine brewing process, where tartaric acid forms a sludge and has to be removed from the final product (2). Wine is essentially sugar fermented by yeast into alcohol and byproducts.

Of course, humans do not produce this material. However, when yeast in the intestinal tract are fed sugar from the diet, they produce tartaric acid--just like the yeast in the wine-making process does.

Tartaric acid is also extremely elevated in many patients with fibromyalgia who also experience muscle and joint pain. Tartaric acid was initially discovered by Dr. Shaw, Director of the Great Plains Laboratory, in the urine of two autistic brothers with muscle weakness so severe that they could not stand up (4).

Where the Yeast is & Why it Causes Problems

Tartaric acid is an analog (or close chemical relative) of malic acid. Malic acid is a key intermediate in the Krebs cycle, a biochemical process used for the extraction of most of the energy from our food.

Presumably tartaric acid is toxic because it inhibits the biochemical production of the normal compound, malic acid. Tartaric acid is a known inhibitor of the Krebs cycle enzyme fumarase (Figure 1) which produces malic acid from fumaric acid (5).

A large percentage of patients with fibromyalgia respond favorably to treatment with malic acid (6). I presume that supplements of malic acid are able to overcome the toxic effects of tartaric acid by supplying deficient malic acid. Treatment with the antifungal drug Nystatin kills the yeast and values for tartaric acid steadily diminish with antifungal treatment (Figure 3).

Fifty percent of patients with fibromyalgia often suffer from hypoglycemia (7)--low blood sugar--even though their diet may have adequate or even excessive sugar. The reason may be due to the inhibition of the Krebs cycle by tartaric acid.

The Krebs cycle is the main provider of raw materials such as malic acid that can be converted to blood sugar (Figure 2) when the body uses up its supply. If sufficient malic acid cannot be produced, the body cannot produce the sugar glucose which is the main fuel for the brain. The person with hypoglycemia feels weak and their thinking is foggy because there is insufficient fuel for their brain.

Figure 1 - Site of tartaric acid inhibition of the Krebs Cycle, the major energy producing mechanism of the cell.

In addition to the inhibition of energy production, tartaric acid prevents the production of malic acid, which is a key intermediate in the production of glucose in the process of gluconeogenisis, the principal fuel for the brain.

Krebs Cycle

Figure 2 - Patient with high tartaric acid was started on the antifungal drug, Nystatin, and tested while on this drug. Even after 68 days, tartaric increased when the dose was reduced in half and then decreased again when the full dose was restored.


Contributing Factors

Most of the time the yeast are present only in the intestinal tract, not in the blood and other organs. However, the tartaric acid and other compounds produced by yeast in the intestine are absorbed into the bloodstream and may enter all of the cells of the body.

Dr. Paul St Amand noticed that patients with fibromyalgia had high amounts of dental tartar on their teeth and speculated that similar deposits in the muscles and ligaments might be causing the pain of fibromyalgia. It's possible that tartaric acid is the compound found in the dental tartar and that crystals of this substance may be causing the muscle and joint pain, just as kidney stones cause kidney pain.

The two main causes of the yeast overgrowth are use of broad-spectrum antibiotics and the high sugar and carbohydrate content of the American diet (Figure 3). These antibiotics kill most of the normal bacteria (germs) in the intestinal tract, but do not kill organisms such as yeast (8-15).

As a matter of fact, some yeast grow faster in the presence of antibiotics. The reason fibromyalgia commonly follows traumatic accidents may be related to the use of antibiotics to treat trauma.

Sugar consumption is the second major factor in causing yeast-related illnesses. The average American consumes 10 times more sugar than Americans in the time of George Washington(about 150 lb per year). In a study done in mice, those mice receiving sugar in their water had 200 times more yeast in their intestine than mice receiving plain water (16).

Other factors that cause yeast overgrowth may include stress, birth control pills, viral infections, and a weak immune system.

Figure 3 - Factors that Contribute to Yeast Overgrowth

Testing - What to Expect and How it can Help

Some doctors assert that everyone has yeast in their intestine, and if yeast were the cause of fibromyalgia, everyone would suffer from fibromyalgia-like symptoms.

However, the important question is not about the presence of yeast. The critical factors are the quantity of yeast and the kinds and amounts of toxic products they produce.

To illustrate: everyone in our society has carbon monoxide in their blood and can tolerate a low value. However, when the amount of carbon monoxide increases, some individuals feel depressed, some have headaches, some develop muscle weakness, some feel tightness in the chest or angina, some experience nausea and vomiting, some become dizzy, and some develop dimming of vision. As amounts of carbon monoxide increase, symptoms may include convulsions, coma, respiratory failure, and death. Individuals who recover from severe carbon monoxide poisoning may suffer residual neurological damage. Different people will respond with different symptoms to the same concentration of toxins.

So why would it be surprising that exposure to a wide range of toxic yeast products--at different times and at different ages--might produce different symptoms? No one would challenge a suggestion of a connection between carbon monoxide and all of the diverse symptoms associated with carbon monoxide exposure. That connection is accepted because carbon monoxide is easily measured in blood.

The toxic yeast products were just discovered, but as knowledge of them increases, acceptance of the yeast-related illnesses will increase.

As the philosopher Schopenhauer said, "All truth goes through three stages. First, it is ridiculed. Then, it is violently opposed. Finally, it is accepted as self-evident." Within five years, people who ignore the importance of yeast-related illness will be in the same camp with those in the Flat-Earth Society.

Frequently Asked Questions About Yeast Testing

The yeast problem can be treated with a combination of a low sugar/low carbohydrate diet, an antifungal drug to kill the yeast, and probiotics, which are supplements of Lactobacillus acidophilus to restore beneficial bacteria to the intestinal tract.

Malic acid and magnesium supplements will help the patient until the yeast problem is resolved (which may take about two months). The reduction in tartaric acid in urine following antifungal treatment is illustrated in Figure 2.

The test evaluates inborn errors of metabolism that can be detected with this technology (called GC/MS, such as PKU, maple-syrup urine disease, and many others). In addition, we check for other problems such as vitamin deficiencies and the abnormal metabolism of catecholamines, dopamine, and seretonin

We currently quantitate 65 substances, but also evaluate other substances that are not quantitated. For example, in one report, high kynurenic acid indicated a need for vitamin B-6, and an elevated glutaric acid indicated a requirement for coenzyme Q-10. Even if you don't have the yeast problem, our test may still be beneficial to you!

A medical practitioner who is licensed to order urine testing in your state must approve the test order. Regulations vary from state to state so an approved medical practitioner could be a medical doctor (MD), osteopath (DO), nurse practitioner, chiropractor (DC), or naturopath (ND).

If you have difficulty in getting your physician to approve the test, we can refer you to a physician in most locations in the United States and in some foreign countries. The test is reimbursed by most insurance companies but, of course, we cannot guarantee reimbursement.

The test requires that a morning urine sample be shipped to The Great Plains Laboratory, and results are usually available within two weeks, including a recommendation to your physician for treatment.

No, there is no interference from any known drug or supplement. The malic acid and magnesium products will not affect the test results.

However, if antifungal supplements or drugs are taken before the test, you will probably get a lower value for the yeast byproducts. We advise you to get the test first so that you will know what the starting point is.

This test could benefit you if we document a defined biochemical disorder. Of course, more important is the possibility of reversing the fibromyalgia if the yeast problem is a significant factor.

We will be glad to help you and your physician develop a suitable therapy based on your test results.

Unfortunately, no. There is no other laboratory that routinely analyzes the same compounds as this laboratory (including Labcorp, SmithKline, or Mayo Medical laboratories). If you do not specify our laboratory, your urine will be sent to one of the large reference labs which cannot accurately evaluate your condition. Most of these labs only test for inborn errors of metabolism.

We are set up for Medicare, but we do not yet have Medicaid authorization

We would be happy to work out an installment plan for you. We can also accept MasterCard and VISA payments.

Download the Fibromyalgia Brochure

View the Fibromyalgia Brochure (PDF)

Notes on Our Testing from the Book
Detoxification and Healing: the Key to Optimal Health

"Dr. Shaw’s work is very recent and as I write this he has just opened a new lab… The reason for telling you about his work is to ask you to think about the implications and watch as his ideas develop over the next few years. As you will see...there is other evidence to support these ideas and, if you understand the implications, there are things you can do now that will reduce your risk of ill health while continuing to watch from the sidelines."

Dr. Baker, the author of Detoxification and Healing, is a graduate of Yale University School of Medicine and is board certified in obstetrics and pediatrics. Dr. Baker was director of the Gessell Institute of Human Development and has taught at Yale Medical School, and is the author of dozens of articles and several books about health and nutritional biochemistry.

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  • "Tartaric acid." Microsoft Encarta 96 Encyclopedia on CD ROM.

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