"Invasive candidiasis is a fungal infection that can occur when Candida yeasts enter the bloodstream. Candidemia (a bloodstream infection with Candida), is extremely rare in people without risk factors," http://www.cdc.gov/fungal/Candidiasis/invasive/
The Candida claims I don't believe is the very broad "Chronic Candida" diagnosis propagated by segments in alternative medicine that's kind of in-between the ones above and is blamed for so many symptoms and other chronic health conditions.
An example alternative medicine explanation:
What Is Candida?
Candida albicans has the ability to change from normal yeast to a pathogenic fungus. The fungal form creates excessive toxicity that will affect the way every organ, tissue, and cell functions. Systemic Candida occurs when fungal Candida has spread throughout the body.
Systemic Candida can contribute to or create many problems in the body. Common major Candida symptoms may include: Sugar or sweet cravings, gas, bloating, fatigue, low energy, allergies, sinusitis, acid reflux, hormonal imbalances, brain fog, Depression and arthritis. http://www.candidaplan.com/new/what_is_candida/
This alternative medicine diagnosis has been referred to by different names (which can be confusing) such as Chronic Candida, Candida overgrowth, Systemic Candida, Candidiasis, or simple Candida, and this diagnosis is the one that I'm saying is really caused by Malnutrition, which can make people's immune systems weak and, therefore, more susceptible to getting the kinds of Candida infections conventional medicine accepts that I listed above.