Like small intestinal bacterial overgrowth, SIBO, small intestinal fungal overgrowth, or SIFO, is rampant, far more common than I ever thought. In SIBO, undesirable bacterial species, mostly Enterobacteriaceae like E. coli, Shigella, and Campylobacter, proliferate and ascend up the length of the gastrointestinal tract, reaching as high as the esophagus. In SIFO, fungal species likewise proliferate and ascend up the entire length of the gastrointestinal tract. Skin rashes, allergies, unexplained fatigue, sugar cravings, and the presence of an autoimmune condition should trigger a suspicion for SIFO. Unlike SIBO that remains confined to the 30+ feet of the gastrointestinal tract (for the most part), SIFO has the peculiar ability to seed other organs such as the skin, toenails, even brain. (There is growing evidence that fungal infestation of the brain is a major factor in Alzheimer’s dementia, a fascinating topic that we are going to explore in future.)
It is not entirely clear why fungal overgrowth has become so common, but it is likely due to exposure to prescription antibiotics, antibiotic residues in food, overconsumption of sugars and alcohol, and other factors, thereby sharing many causes with SIBO. This may be at least part of the reason that SIBO is often accompanied by SIFO at least 50% of the time and vice versa.
In the Undoctored world, curcumin is at the top of the list of our choices for anti-fungal agents if fungal overgrowth is detected in the stool, in a duodenal aspirate, or is suspected due to identification of fungal growth elsewhere in the body. Among the factors that make curcumin our preferred anti-fungal agent are:
- Proven anti-fungal efficacy—Curcumin has been compared in a head-to-head trial to treat vaginal Candidal infection and curcumin proved as effective as conventional clotrimazole; the curcumin was also much less disruptive over the vaginal microbiome. Because fungal species can evade anti-fungal efforts by sequestering themselves in a biofilm, curcumin may have the advantage of reducing this protective biofilm and exposing fungi for eradication.
- Reduced intestinal permeability and strengthening of the intestinal barrier—Part of SIBO and SIFO is increased intestinal permeability that leads to, for instance, metabolic endotoxemia (the entry of bacterial and fungal breakdown products into the bloodstream), a toxic situation. Curcumin has been shown to exert beneficial effects across several aspects of the intestinal barrier.
- There is almost zero absorption of curcumin into the body with trivial blood levels measured, even after taking substantial doses. Ingested curcumin therefore makes its way through the entire length of the intestine with 90% excreted in the stool. Unfortunately, this has caused nutritional supplement manufacturers to try to force absorption by adding such things as piperine or creating nanoparticle or liposomal emulsions. But I believe that they may be missing the point: We want curcumin to stay in the intestines to exert effects on the intestinal barrier and exert anti-fungal and limited antibacterial effects. (There may be other benefits experienced if curcumin is absorbed, but there are considerable advantages to curcumin’s actions within the intestines.)
Intestinal fungal overgrowth is, I believe, like SIBO an exceptionally common phenomenon that underlies dozens, if not hundreds, of health conditions, either causing them in the first place or complicating them. Look for fungal overgrowth and you will find many, many people with fungal overgrowth in people with conditions such as obesity, type 2 diabetes, autoimmune and neurodegenerative diseases, rosacea and eczema.
Undoctored Inner Circle Members can find a detailed Advanced Topic on fungal overgrowth in the Inner Circle website. In our Inner Circle discussion, you will see that, while we begin with curcumin, we add at least one or two more anti-fungal agents due to the propensity for fungal species such as Candida albicans and Malasezzia to evolve resistance to single agents. Introducing more than one agent simultaneously stacks the odds in favor of effectively reducing fungal populations in the intestines.