This same yeast is also the cause of oral thrush, male yeast infections, skin rashes, diaper rash, and some nail infections.

Yeasts are single-celled fungi. Other types of fungi are molds and mushrooms. Fungi are more closely related to animals than plants, although you wouldn't be able to tell that from looking at them.

Because their cells are very similar to our own, many chemicals that are known to kill fungi can also damage or kill human cells. And some anti-fungal medications can also kill off the beneficial bacteria that live in our gut.

This makes the process of finding safe and effective anti-fungal medications even more difficult for researchers.

Scientists have found over a thousand different species of yeasts so far, and there are probably many more that have not yet been discovered. Yeasts tend to reproduce very quickly under the right conditions, and this makes them a favorite organism for scientists who study DNA and genetic markers.

It also makes yeast infections difficult to fight when your own body becomes a ?perfect? environment for the fast growth of yeast.

Most people, (at least 80% of us), have Candida living in or on our bodies. C. albicans lives on the skin and in the mouth and gastrointestinal tract, along with many other living organisms. Most of the time, the yeast is perfectly harmless.

Candida is an opportunistic infection, which means that it's usually benign, but it can explosively reproduce and become invasive under certain conditions. This is especially troublesome if the body's own immune system is impaired for some reason and unable to fight off the infection.

When the yeast is in its harmless round form you would never know it was there, even though it is probably living on your skin and in your lower intestine and vagina all the time.

However, Candida yeast is dimorphic, which means that the same yeast cell can take two different forms, depending on the environment in which it is living. If a chemical change in the body causes the yeast to be ?stressed,? the shape of the Candida cell changes and it becomes invasive.

Candida switches from the benign round form to the invasive form when it encounters specific environmental conditions, such as a changing hormone balance or acidosis, which is common among diabetics. In a completely healthy individual, Candida will not become infectious, so a Candida infection is always a symptom of an underlying imbalance or a temporary failure of the immune system.

During this infectious phase, the yeast cell has long threads (called hyphea and pseudohyphae) that contain special proteins that allow it to attach itself to human cells on the skin and mucous membranes, and toxins emitted by the yeast cell can then cause irritation and inflammation.

Invasive yeast can also stick to the surfaces of prosthetic devices and sex toys. And invasive Candida has been found on all sorts of hospital surfaces, including food, air-conditioning vents, and even the clothing of hospital staff.

In its infectious phase, Candida can cause a vaginal discharge, discomfort, itching, rashes, or worse. It is impossible to ignore the presence of this fungus when it's on the warpath. Then, just as quickly, the yeast can turn back into its peaceful phase again, and your life goes back to normal.