In part one of this blog (Part One) I discussed the new theory that Alzheimer’s Disease (AD) is caused by a number of different fungal species, a mix of which were found in the autopsied brain tissue of those who died with advanced AD. Now I will go into the 10 types of fungus that were discovered, with the hope that by identifying where they are found, we can avoid them to some degree. Then, in a following blog I will look at methods by which we can kill, or at least keep in check, those fungi that do get into our bodies.


The Fungal Species Linked to Alzheimer’s Disease


Candida Albicans

This is the most familiar of these nefarious fungi, since most of us with an interest in natural healing are aware of its prevalence as a modern ailment, most often a byproduct of excessive antibiotic use. It is mostly recognized in the medical system as a cause of oral (thrush) and genital infections (vaginitis).


C. albicans is of a species known scientifically as “dimorphic” which means that, while it is commonly referred to as a “yeast” infection, it is an organism that can manifest in a yeast or fungus form. When cultured in a lab, C. albicans grows as a yeast cell, but environmental changes in temperature and pH results in it morphing into a fungal form. And there are those in the Natural healing field who believe this fungal form is a cofactor in cancer growth.


C. albicans is a normal constituent of the gut flora, and is kept in proper constraint when we have a healthy microbiome. But, when our gut flora is disrupted, by a poor diet high in sugars, antibiotic use, and/or mercury fillings, the candida migrates out of the areas where it is controlled and into areas where it can proliferate and cause damage. Candida overgrowth is also common in those who have compromised immune systems. Candida becomes a “super infection” when it becomes resistant to anti-fungal drugs, and then is treated with antibiotics, which in turn leads to antibiotic-resistant strains.


As I mentioned before, given the fact that C. albicans exists within us already, and given how prevalent overgrowth is due to modern living, I personally believe that this is the gateway fungus, the one that opens the door (creates the environment) for the other more obscure species to take root and colonize.


Candida Ortholopsis

There are many forms of candida, and one found in the plant kingdom is C. ortholopsis. Brazil in one of the major producer of tomatoes in the world, and given that the tomato is one of the most consumed food ingredients in the world, it was logical that Brazilian researchers would do research on tomatoes.


When they did, they found tomatoes to be heavily contaminated with C. ortholopsis, which, even though the levels declined as the fruit ripened, still had a considerable amount left on the fruit by the time it was ready to pick. The researchers concluded that more work needed to be done on postharvest fungal disease control, and that it was essential that people efficiently clean tomatoes before consuming them. Considering the appalling state of some mass food production facilities, it may be likely that tomato juice and sauces, and poorly cleaned fresh tomatoes, may be a source of this fungus among us.


Candida Tropicalis

This is a common medical yeast pathogen considered to be more pathogenic than C. albicans. While C. albicans has historically been the major pathogenic yeast species responsible for causing candidiasis in those with compromised immune systems, infections due to C. tropicalis has been increasing dramatically worldwide. Though medical authorities are not sure why this increase has occurred, they do know that its evolved resistance to the common antifungal treatment (fluconazole) may be part of the equation. C. tropicalis is found naturally occurring in seawater, sea sediments, mud flats, marine fish intestine, mangrove plants and marine algae, as well as shrimp, indicating its wide distribution in tropical and subtropical marine environments. It can also be cultured from various fruits and soil.



This genus of fungi, which includes some of the most common indoor and outdoor molds, is often found on plants (both living and dead). Some of this species are plant pathogens (tomato leaf mould) while others parasitize other fungi (no honor among fungi; but gives us an indication of how fungi can work in tandem). Spores of Cladosporium are dispersed on the wind, and they are often abundant in outdoor air, where they can cause allergies in susceptible people, and, in high amounts they can worsen asthma, and other respiratory diseases.


Indoors, Cladosporium species may grow on surfaces where excessive moisture is present. Not generally considered a serious pathogen to humans, Cladosporium species have been known to cause infections of the skin, toenails, and in the lungs and sinuses.


Malassezia Globosa and Malassezia Restricta

The genus Malassezia comprises a group of superficial dimorphic fungi occurring as normal skin flora on the human body, and on many animals. This particular fungus is found in areas of the body with many sebaceous glands (face, scalp, and upper part of the body) because it requires fat to grow. Since the majority of the brain is comprised of fat (about 60%), we can see it would be an ideal home for this fungus to grow in.


And, being dimorphic (like C. albicans) it can occur as either yeast or fungi, depending on its environment. The Malassezia species of fungus is considered to be the cause of most skin disease in humans, occurring when the yeast phase converts to the mycelia (fungal) phase. This conversion can occur due to: high sebum levels at puberty; excessive sweating; hot weather; application of oils to the skin; malnutrition; administration of systemic steroids; the presence of Cushing’s disease; pregnancy; oral contraceptives; antibiotics; or immunosuppressive drugs. Obviously, a combination of these factors would make the pathogenic conversion to fungus more likely to occur.


It has been known to cause hypo-pigmentation or hyper-pigmentation (loss of pigmentation or darkening of pigmentation) on human skin, and the species M. globosa is the most common cause of dandruff, itchy scalp, and seborrhoeic dermatitis.


Neosartorya Hiratsukae

N. Hiratsukae is a member of the Aspergillus fungus family, though there is not a whole lot of information available on this particular member. Aspergillus spores are omnipresent in the air, but are considered generally benign, and do not cause illness, except in those with allergies, lung diseases, or a weakened immune system. Aspergillus is found in unusually high amounts in air conditioning units, compost, and damp or flood damaged buildings, and has been linked to some plant diseases, and food spoilage (commonly found on starchy foods like bread and potatoes).


Safe species of Aspergillus are used to make citric acid, Sake (rice wine), and the so-called “plant enzymes” that are sold as digestive enzymes in vitamin stores.  But, there are a number of species of Aspergillus that are considered seriously pathogenic, and certainly this one, N. hiratsukae, falls into that camp. It has been found in diseased people occasionally, in different parts of the world. N. hiratsukae has been found in diseased skin, lungs, throat, kidneys, sinuses, and brain, but these were all rare occurrences. On the other hand we don’t find what we aren’t looking for, so we may hear more about this fungus as the medical system expands on these limited findings.


One case is of particular interest here: A 75 yr old Brazilian woman admitted to hospital in 1999. Her symptoms included confusion, memory loss, involuntary movements in the upper right arm, and a walking disorder, combined with a loss of balance, that initially led to a diagnosis of Parkinson’s disease. Eventually they discovered her brain to be infected with N. hiratsukae and, even though she was treated with anti-fungal drugs, she died shortly thereafter.



Members of the genus Phoma are found throughout the world with over 2000 species having been identified. They are found in soil and on various plants, and some species are known pathogens to plants and humans. Phoma is a common soil fungus which can attack weak or damaged plants, and is a specific pathogen of cultivated plants, especially beets and sweet potatoes, in which it causes rot.


This fungus causes a condition known as Phoma blight, showing as a fading and withering of the plant leaves, ultimately killing the plant, and potentially spreading to other plants in the vicinity. One species of Phoma causes root rot in alfalfa, and other legumes, in areas with harsh winters, while other strains have been found in cereals, fennel, sorghum, pearl millet, and various types of corn, and are especially common in alfalfa sprouts.


Frequently found indoors, Phoma can contaminate humid surfaces, and can be often seen in painted walls as they deteriorate, producing colored spots, usually pink or purple. One strain (P. fimeti) has been found in bathrooms and washing machines.


Not currently believed to be dangerous to humans, anecdotal evidence has linked P. betae to allergies, asthma, and lung inflammation, in sensitive individuals. As well there is one documented case of Phoma causing inflammation of the cornea of the eye (Keratitis).


Sacharomyces Cerevisiae

S. cerevisiae is a species of yeast that has been with humanity since the dawn of brewing and baking, and is the same yeast used today for those purposes. It is believed to have been originally isolated from the skin of grapes. As well, it is the yeast that is a byproduct of beer making (brewer’s yeast), or cultivated on molasses (the better tasting engevita yeast), and sold as a nutritional yeast, being a rich source of B vitamins. And it is the yeast used to make the new generation of “food-form” vitamins, and for brewing tonics like Floradix and BioStrath.


Up until recently, S. cerevisiae was rarely considered to be a cause of infection or disease in humans. However, since it was found among the mix of fungi in the aforementioned brains of AD patients, I dug around to see what kind of potential it had to be dangerous, and what I found was that it may be a growing problem.


Personally, I eat a lot of engevita yeast, which I have always assumed is good for me, but this research has me questioning that assumption. While those with candida overgrowth (systemic yeast infection) are advised not to consume yeasted products during treatment, it has always been assumed that nutritional yeast was safe because it is inert (not active, as is necessary for making beer, bread or wine). And, in fact, some health advocates believe that eating nutritional yeast actually protects us against candida overgrowth.


So I was surprised to find that there are some instances of this yeast leading to life-threatening “fungemia” (caused by the presence of yeasts in the blood; its symptoms have been described as “flu-like”). This was traced to the use of the probiotic “Sacharomyces boulardii”, commonly sold in vitamin stores.


S. boulardii is the only probiotic that is a form of yeast, rather than bacteria, and is used medically in European hospitals. While it does have a good track record for treating C. difficile-associated diarrhea, as well as traveler’s diarrhea, once it got into the blood stream it became life threatening. The first thing to observe here is that S. boulardii is considered to be genetically identical to S. cerevisiae.


In 2003 researchers found 3 patients with S. cerevisiae infection in an intensive care unit, they had all been treated with an S. boulardii product (Ultralevura by Bristol-Myers Squibb) via a nasogastric tube (from the nose to the stomach), for just over a week of treatment. Further examination of the literature found 26 patients who developed fungemia following probiotic therapy with S. boulardii and the majority of these were receiving enteral feeding (tube to the stomach), or had a central venous catheter (inserted directly into a vein), and all were receiving antimicrobial medications. (Seventeen of the 26 patients did in fact die.)


The infection in these cases seemed to be due to the tubes or catheters becoming contaminated on the outside, occurring when the health practitioners were mixing in the probiotic, so contamination was a direct result of the medical technology being used, and would not generally occur for someone simply swallowing the pills.


Since disease resulting from S. cerevisiae is extremely rare in healthy people, the primary recommendation from this particular research was that “S. cerevisiae probiotics should be carefully reassessed, particularly in immuno-suppressed or critically ill patients.” However, what was also pointed out is that the number of cases S. cerevisiae infection reported has gone up every decade since the 1970’s (4 cases reported during 1970–1980, 10 reported during 1981–1991, and 46 reported during 1992–2004).


All in all, after searching the literature, the researchers found 60 cases of fungemia due to infection by S. cerevisiae, which were linked to a wide variety of clinical symptoms including: pneumonia, emphysema, liver abscess, peritonitis, vaginitis, esophagitis, urinary tract infection, cellulitis (skin infection), unexplained fever, or septic shock. S. cerevisiae has also been associated with Crohn’s disease, and has been found in patients with asthma, ulcerative colitis, and diarrhea.  (Research)


Since we ingest this yeast commonly in breads, alcoholic beverages, and as a nutritional supplement, it behooves us to try and understand where the danger might lay. As observed above, the real danger is when the yeast gets into the blood stream, as was the case with those in the hospital who were infected through contaminated catheters, etc. I consider “leaky gut syndrome” to be a possible explanation for why we may be having more health issues around this yeast.


Since many people now have a porous gut lining, due to candida yeast overgrowth, antibiotic use, GMO foods (“Round-up” residue), and a lack of particular nutrients, we may be having a problem with this yeast that did not occur amongst our ancestors. Leaky gut is essentially an unfiltered portal to the blood stream, and may be an avenue for this yeast to infect susceptible people.  (For more information on the leaky gut and how to fix it, see the blog “How 3 Nutrients Can Heal Most Ailments” (Blog)


Sclerotinia Borealis 

There is not a whole lot of information on this plant pathogen found in Northern Europe, Japan, and North America (in the Northern States and Canada). Sclerotinia borealis is a fungus that often grows on lawn and wheat seedling under the snow in winter, inducing “snow mold disease”, and its spores are disseminated by long, rainy autumns.


This low temperature fungus grows on forage grasses, lawn grasses, and some cereal crop plants, most commonly barley, rye, triticale and wheat. Given the cold environment in which it thrives, it enters the food chain most notably though “winter rye and winter wheat.” However, so far, aside from the AD study that we began with, there has been no link between this fungus and disease states in humans or animals (at least none that I could find).


In Part 3, I will look at the prevalence of molds and fungus in our environment and foods, and examine why coconut and MCT oil may be so effective at treating and preventing AD.

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