The Ultimate Resource for Fungal and Yeast Infections

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Candida Info

Yeast Infection -- Candida Albicans, And The Symptoms And Treatments Of Candidiasis

Page 1 -- Yeast Infection Background Information (this page)

Page 2 -- Yeast Infection Symptoms, and the “Candida Related Complex”


For background information, please see our page FUNGUS & YEAST GENERAL INFORMATION.


The terms "yeast" and "fungus" and "mold" are often used interchangeably. For simplification, all species of yeast and fungus which grow in the human body may be lumped together for this discussion and simply called "yeast."

Like various kinds of virus and bacteria, fungi are omnipresent; fungi, molds and yeasts are carried through the air (primarily as spores), as well as being distributed by other means. Candida is found in the environment, particularly on leaves, flowers, water, and soil.

Yeast Tissue Penetration

Some fungi can alternate between a yeast phase and a hyphal phase, depending on environmental conditions. Such fungi are termed dimorphic (with two shapes) and they include several that cause disease of humans, the most prominent being Candida albicans.

Candida albicans in yeast and hyphal forms
    The dimorphic nature of Candida can be seen in the above photographs, on the left in its spherical form, and on the right beginning its hyphal form.
Yeast in hyphal form
    Of major concern in human illness is that the Candida hyphae penetrate into tissues in pursuit of food. The above image more dramatically presents Candida in its hyphal form -- imagine this mass permeating your intestinal wall and you'll instantly understand the difficulty of getting rid of it.

The majority of fungal infections in the United States are caused by Candida. Of those that are clinically identified, approximately 50% are due to Candida albicans; the remaining 50% are primarily caused by C. tropicalis, C. glabrata, and C. parapsilosis, with minor percentages represented by C. krusei and C. lusitaniae.

Candida is a member of normal flora of skin, mouth, vagina, and stool. Its normal habitat is the mucosal membranes of humans and other warm-blooded animals, where it grows as a yeast and typically causes little or no damage. In fact, it can be isolated from the mucosa of up to 50% of humans - from the mouth, the gut, the vagina or, less often, from the surface of the skin.

In some circumstances, however, C. albicans can become pathogenic, invading the mucosa and causing significant damage. This usually happens when a variety of predisposing factors cause the yeast population to multiply, escaping the normal competition from resident bacteria which keep the yeast population in check.


Small amounts of yeast and other fungal organisms compose a normal part of the body's microflora. They normally are well tolerated by those with healthy immunity. If they increase in number, however, they create additional stress to the immune system, which can lead to an overgrowth. Conversely, those with weakened immune symptoms become susceptible to overgrowth of these (and other) microbial agents. The growth of yeasts are normally kept in check in the intestinal system by the presence of Acidophilus and other beneficial bacteria. Situations that negatively affect the immune system or the normal intestinal flora can permit excessive yeast growth.

Yeast Infection Factors

Candida overgrowth is commonly believed to be associated with a number of potentiating factors, including:

  • steroid hormone medication such as cortisone, or corticosteroids, often prescribed for skin conditions such as rashes, eczema, or psoriasis, as well as for systemic conditions such as rheumatoid arthritis.
  • prolonged or repeated use of antibiotics which are frequently given for urinary and ear infections, sinusitis, bronchitis, and other infections; Candida overgrowth can be triggered at a very young age when children are first being treated with antibiotics.
  • ulcer medications such as "Tagamet" and "Zantac" which reduce the amount of acid in the stomach and intestines.
  • oral contraceptives and estrogen replacement therapy.
  • immune-damaging illnesses such as diabetes.
  • suppressed immune system from AIDS/HIV, radiation and chemotherapy, and organ transplant surgery.
  • a high sugar and starch diet.

Yeast Infection and Sugar

Sugar in the diet can greatly contribute to Candida overgrowth. Yeast lives on sugar -- brewing and winemaking depend on yeast to digest sugar, producing alcohol as a waste product. Starches (carbohydrates) in breads, pasta, and potatoes are converted rapidly by our digestion process into sugar. Carbohydrates begin to break down into sugar with our saliva, and simple carbohydrates can be converted into sugar in minutes. Important So, a diet high in sugar and starch feeds yeast, and some strains of yeast like Candida can grow very quickly. See our page on Candida Diet for more information.

Yeast Infection and Antibiotics

Antibiotics may be the single greatest cause of Candidiasis, because antibiotic treatment for infections kills the "good" intestinal bacteria, as well as the targeted infection-causing bacteria. Normally yeast that is present in the gastrointestinal tract is held in check by the presence of "beneficial flora" that control yeast and other potential invaders by crowding them out and by producing natural antifungal substances. Acidophilus and other good bacteria produce most of our B vitamins, including biotin. Important Biotin suppresses the ability of yeast to form hyphae, thus preventing the yeast from entering its invasive state. However, when biotin is lacking, as a result of damage by antibiotics to Acidophilus, Bifidobacteria, and other intestinal microbes, yeast has a chance to change from it's simple yeast form into the damaging fungal form.

Healthy bacterial colonies in the intestines can usually withstand one or two short episodes of antibiotics without serious harm. If, however, use of antibiotics is frequent or prolonged as with a course for acne treatment or a more difficult infection, then the spread of Candida becomes inevitable, especially if the death of the bacteria is accompanied by a diet that promotes the growth of yeast. A vicious cycle may develop as a result. Antibiotics foster the growth of yeast, which suppresses the immune system. An individual with suppressed immune function is much more susceptible, not only to Candidiasis but to bacterial infections, which are then treated with antibiotics, which, in turn, increase the growth of Candida and so on.

Frequently, candidiasis is caused by a combination of factors. Over a few years a patient may have had several series of antibiotics for a variety of conditions, may have been using steroids, perhaps in the form of birth control pills or treatment for arthritis or psoriases, and may have consumed a Coca-Cola, Pop Tart, Dunkin Donuts, French fry, pizza, high sugar, high starch diet. Consequently, conditions are created for yeast to grow, causing an opportunistic infection.


Candida albicans exists quite normally in low concentrations on the skin and inside the digestive, respiratory and reproductive organs. Because Candida is a normal constituent of human micro-ecology, the mere presence of Candida is not sufficient to make a diagnosis of "infection."

Types of Yeast Infections

Candid Albicans may cause jock itch, athlete's foot, constipation, diarrhea, bloating, poor digestion, burping, lower gas (flatulence), fingernail and toenail infections, and diaper rash and thrush in infants. C. albicans also causes vaginitis - inflammation and invasion of the vaginal mucosa, especially during the third trimester of pregnancy and in women who take the pill. The predisposing factors seem to be hormonal, associated with changes in the balance of cell types in the lining epithelium of the vagina. A similar condition termed stomatitis is common in people who wear dentures. Candida can adhere to denture resin, and high sugar levels in the diet can also increase the adhesiveness of the yeast.

In some of these conditions, the infection and its cause are obvious. One of the best examples of this disease is termed thrush - a white, crusty speckling of the tongue and the back of the throat caused by a rapid and uncontrolled growth of Candida. This is common in newborn babies, perhaps resulting from passage through an infected birth canal from a mother with vaginitis. It is also common in AIDS patients and people who have had a prolonged course of antibacterial therapy.

Systemic Yeast Infections -- Candidiasis

Systemic Candidiasis is a more serious condition, when yeast cells proliferate in the circulatory system. This can occur after invasive surgical techniques, including the insertion of intravenous catheters to which the yeast cells adhere, providing a base from which the cells can bud and be disseminated. When transported by the blood stream, Candida can infect almost any organ of the body, and can be fatal. The technical definition of systemic yeast is yeast growing throughout the body and blood. This very rarely happens, and when it does, the results can be deadly. The victims most commonly are immune-system compromised -- PWA’s (People With AIDS), and those with artificially suppressed immune systems for organ transplantation and cancer therapy. In the immune-compromised, fungus and yeast can transit the blood stream to the heart, lungs, brain and other organs, growing violently, and sometimes uncontrollably.