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Combat SIFO (Small Intestinal Fungal Overgrowth)

If you have been reading my blog for a while, you have most definitely heard of SIBO (small intestine bacterial overgrowth). But what about small intestine fungal overgrowth, aka, SIFO?

Similar to SIBO—wherein too much bacteria grows in the small intestines—SIFO is characterized by the over-proliferation of fungi, most commonly the Candida species, which accounts for 97 percent of SIFO cases. Although everyone’s small intestine is home to a small number of fungi, when our gut microbiome gets disrupted—whether by poor diet, disease, or medication—it creates an environment where fungi can grow out of control. If left untreated, SIFO can lead to digestive issues, chronic inflammation, lowered immune response, cognitive issues, impaired nutrient absorption, and damaged intestinal mucosa (increased intestinal permeability AKA leaky gut). And, although the correlation as yet remains unclear, Candida overgrowth is also associated with gastric ulcers, Crohn’s disease, and ulcerative colitis.

What Causes SIFO?

For fungi to grow uninhibited in the gut, they need the right environment. Some factors—like diet—are totally within our control, while others are not. SIFO can have more than one cause, including:

·       Diets high in refined sugar, processed food, and/or alcohol

·       Frequent or prolonged use of antibiotics

·       Long-term use of steroids and/or proton pump inhibitors (PPIs) (i.e., Prevacid, Prilosec, Nexium)

·       A weakened immune system from autoimmune disease, diabetes, or those undergoing immunosuppressive therapy

·       Slow intestinal motility resulting from conditions such as gastroparesis, Hirschsprung’s disease, Ehlers-Danlos syndrome, or thyroid disorders

·       Being an older adult or a young child

Common Symptoms Make for a Tricky Diagnosis

Unfortunately, SIFO typically manifests as common digestive problems. Worse still, SIFO and other digestive disorders, including IBS and SIBO, are not mutually exclusive, so those common symptoms can also overlap. These include:

·       Gas, bloating, and/or belching

·       Nausea

·       Fatigue

·       Diarrhea and/or constipation

·       Abdominal and/or joint pain

·       Skin issues such as itchy rashes

·       White coat on tongue (oral thrush)

·       Urinary tract infections (UTI)


What tends to set the condition apart, however, is that the internal fungal overgrowth, mainly yeast, can spill over to other areas of the body.

Because its symptoms are so common, the right test is needed to determine if you have SIFO. It’s important to rule in/out SIBO as well, as symptoms are similar, and you can have one or both of the conditions, and they both need to be treated differently. SIBO can be tested for with a SIBO breath test. SIFO, on the other hand, can be diagnosed using a procedure known as a small bowel aspirate, wherein a small amount of duodenal tissue and fluid is collected for a culture. An Organic Acids test, Candida antibody blood test or a comprehensive microbiome Stool Analysis can offer insights into fungal overgrowth.

Nutrition as a First Defense

Although there are both traditional and alternative treatments for SIFO, you can create a digestive environment that’s inhospitable to yeast through a low-sugar diet. Tenets include:

1.     Avoid added sugar and refined carbohydrates. Yeast requires sugar to grow, so to prevent or treat SIFO, eliminating a major source of its “food” is key. Candida also uses sugar to create biofilms that allow it to go undetected by your immune system, worsening the problem. By eliminating added sugar and swapping simple carbohydrates for complex ones, you will starve out those fungal colonies.

2.     Eat plenty of non-starchy veggies. Although you shouldn’t eliminate starchy veggies, such as sweet potatoes, squash, or beets, they are higher in carbohydrates, thus making them a better food source for yeast. Focus on green veggies and cruciferous ones like broccoli, Brussels sprouts, and cauliflower.  

3.     Prioritize lean proteins. Protein is an excellent energy source for the body and an important focus as you recalibrate diet. Avoid processed meats like bacon, sausage, and cold cuts while focusing on organic lean proteins, wild-caught fish, and eggs.

4.     Enjoy low-sugar fruit. Cutting out sugar from all sources is vitally important in combatting SIFO, so you’ll want to avoid high-sugar fruit such as bananas, mangoes, and grapes, and focus instead on berries, lemons, limes, and avocadoes.

5.     Limit/eliminate alcohol. In short, alcohol consistently does more harm to your health than good, and that’s no different where SIFO is concerned. Not only can heavy alcohol use negatively affect your immune health, making you more susceptible to a yeast takeover, it can also worsen intestinal permeability brought on by long-term, untreated SIFO.

SIFO Treatment Beyond Your Plate

While proper nutrition is a key part of preventing and/or treating the symptoms of SIFO, sometimes a case will require a more heavy-duty approach to resolve it. Traditional anti-fungal medications used to treat SIFO include fluconazole and itraconazole. Alternative treatments include:

·       Nystatin, an alternative antifungal medication with less side effects than that of fluconazole or itraconazole

·       CandidaStat®, a blend of vitamins and herbs with antifungal and immune-boosting properties

·       The probiotic strains Lactobacillus and Bifidobacterium, research-backed strains known for their antifungal properties as well as their ability to prevent biofilms

·       Saccharomyces boulardii, a probiotic yeast that fights Candida by overtaking it in the gut

Although identifying and treating SIFO can be tricky, it’s not something you have to do alone. If you suspect that you may be suffering from SIFO, SIBO, leaky gut, or any other digestive disorder, please contact me. Together we help identify the root cause(s) of your issues, develop an individualized nutrition and treatment plan, and get you back to feeling your best!


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