Testing for Candida Yeast Infection

Going beyond standard laboratory methods
By Eric Bakker, ND

Candida albicans is a yeast that occurs commonly in the body, and is not a problem in and of itself. The overproliferation of candida, on the other hand, can lead to unexplained discharge, itchy vagina, digestive problems, poor energy, depression, and excessive skin irritation.

A reliable way to test for candida overproliferation is important, but I have not found standard medical laboratory testing to be useful in determining a patient’s level and severity of yeast infections. Most lab tests are designed to discover “diseased” states of the body, and a yeast infection is not a disease in the traditional sense. In addition, there is no reliable test designed to discover or accurately diagnose the very mild or onset forms of candida yeast infections or dysbiosis (bad bacteria).

Lab tests are based on a population of so-called healthy people. There’s a fundamental flaw with this approach: these “healthy” people were never screened for mild yeast infections, only for the severe forms, what is known as a systemic yeast infection.

The second problem with standardized lab tests for yeast infections is that the lab tests are defined and standardized according to statistical norms instead of physiological norms. The test scores are based on math rather than typical signs and symptoms of yeast infections. When the rates of yeast infection are tested within a population, the individual scores are averaged out. The resulting group is called the “mean” and is used to calculate a probability distribution. In this case, the probability distribution is a statistical prediction of how often each score will occur when the adrenal function of a group of people with a yeast infection is tested.

That is not to say that current laboratory tests for candida are not useful for determining and diagnosing candida yeast infections, only that it is important for you and your interpreting physician to understand their limitations and appropriate uses. Listed below are several tests I use to determine yeast infections in the patients who come to our clinic. Some of these tests may be familiar to you, and others you have probably never heard of.

Can’t afford expensive functional diagnostic tests or they are not covered by your insurance company? Not to worry, there are various home tests you can perform that tell you if you have a yeast infection.

Diagnosing Candida Overproliferation

Until quite recently, there was a lack of reliable laboratory investigation techniques to assist healthcare professionals in diagnosing candida overgrowth. This lack of credible and scientifically validated candida testing changed, however, and physicians no longer need to rely only on detailed symptom questionnaires, which can be unreliable to use as a sole diagnostic aid.

As my level of experience grows as a clinician, I find it less important to test each and every suspected yeast infection case. Once you have seen several thousand yeast-infected patients, as I have, you will have seen candida in its many manifestations—there are countless faces of this condition.

You get to understand that candida isn’t just a digestive or vaginal disorder, like some physicians believe. Many practitioners still haven’t figured out that a yeast infection, particularly when chronic, can affect many areas of the body—including even a person’s mood and their ability to think logically.

If you are a person who really wants to know if he or she has an underlying yeast infection, understanding the different tests available to detect any underlying yeast infections or to diagnose a candida yeast infection is certainly a good thing.

Won’t a Vaginal Swab Be Sufficient to Detect My Candida?

Women are often used to their doctor taking a vaginal swab to determine the presence of a yeast infection. It is important to remember, however, that a swab does not differentiate between a candida infection and a colony of normally occurring vaginal candida, because the cotton swab is sampling the surface of the vaginal wall. It will not tell you if the immune system actually is or has been producing antibodies against candida itself. This test will only indicate what is going on locally, not systemically. The other problem with vaginal sampling is that if the patient has used a vaginal pessary or a douche, the area is sanitized to a degree and a swab will return a false negative reading—simply on account of numbers that register too low for detection.

Can you see the problems and false assumptions which can arise from taking a vaginal swab? Don’t get paralysis from analysis—be aware of the totality of symptoms before you assume you have a major yeast infection based purely on the results of a swab.

Three Conventional Ways to Test for Candida

There are three ways you can detect a candida yeast infection, but none are surefire. They are the blood test, the stool test, and the urine test. Now, let’s look a little more in depth, and I’ll give you my opinion, as I have used them all.

Why Do a Blood Test for Candida?

The standard candida test is a blood test to determine the level of candida-specific antibody production in the body. This can be done via the IgG test or the combined IgG/IgA and IgM test. During a candida yeast infection, the body produces specific antibodies as part of its defense mechanism. These antibodies are different from those produced when a host is first exposed to candida, usually at birth. We can pick up these specific antibodies as they circulate freely in the blood.

Gut Fermentation Tests

This is a bit like a drunk-driving test in that a person’s BAC (blood alcohol concentration) is assessed. It sounds crazy, but a similar blood test can be performed to see if you have a chronic case of candida. Acetaldehyde (a toxic organic chemical compound created in the body as alcohol is being broken down) plays a role in yeast infections. A person who suffers from a yeast infection, particularly a chronic case, may appear intoxicated to some degree.

First, a resting blood alcohol level is measured, and then a second sample is analysed after the person consumes some sugar. If any alcohol appears in the blood— and the person has not been drinking any alcohol previously— this suggests fermentation is taking place, which is an indication of candida overproliferation. The test has been further refined to look for a number of different fermentation products. However, this test does not give any information about what is actually doing the fermenting, as there is increasing evidence that many bacteria can provide such a fermentation reaction in addition to candida.

This type of test is not always positive for individuals with a confirmed candida infection, and therefore I find it an unreliable test to perform on the average candida patient. It is a good test to perform, however, on those people who literally feel drunk, spaced out, and do not drink alcohol, as it may help point out which foods or beverages are contributing towards fermentation.

Urine Tests

Like the vaginal swab, this test is only really valid to detect a local presence of candida in the body where candida has caused a UTI (urinary tract infection) or the urine sample picked up candida due to a case of vaginal thrush. With this test, the laboratory technician looks microscopically for the actual presence of a candida yeast infection and also will attempt to culture candida in a small dish. This test is nearly useless to detect a more widespread and chronic case of candida in the body. It is a good test, however, to diagnose and treat the urinary tract locally if the patient suffers from the typical pains of a UTI, as it will soon detect if and what bacteria and yeasts are present.

Home Tests

As I mentioned earlier, there are also simple tests you can do at home. They are the itch test, the craving test, the spit test, the smell test, and the Candia-5 blood test. It is good to combine the tests to get the most accurate outcome.

The itch test is simple: become much more aware of your body for two days. Are you itchy all over? Itching skin is a classic symptom.

Then there is the craving test: become more aware of what you eat, but particularly what you like to eat and how often. Those with a yeast infection will often crave sweets without even knowing it. Try eating no sweet foods for three days and see how you feel. (Fruits and veggies are OK, but avoid citrus.) This test will make a candida sufferer feel terrible—the stronger the craving, the bigger the problem.

The spit test: first thing in the morning, before you put anything in your mouth, spit into a clear glass of water. Check the water every 15 minutes for an hour. If you have a yeast problem, you will see strings dangling down into the water from the saliva, “cloudy saliva” will sink to the bottom of the glass, or cloudy specks will be suspended in the middle. (If there are no strings and the saliva is still floating in an hour, you may not have a yeast problem.)

The smell test: Are your feet abnormally smelly? Breath? Armpits? This often indicates a bad bacterial population in your digestive system as well as around the skin.

Candida is a major problem due to all the sugar many of us consume in our diet, but a proper diagnosis can put you on the road to recovery.


Eric Bakker, ND, has specialized in candida yeast infections for over 20 years. Eric is New Zealand’s leading online naturopath and considered an expert in natural medicine. His extensive writing and research into candida yeast infections can be seen at yeastinfection.org.