Yeast overgrowth can cause a host of far-ranging problems, from physical to cognitive and mental, some experts say. For that reason, some recommend a candida diet — a low-sugar, low-carb diet — to eradicate excess yeast and bring the gut back into balance. Yet this approach is not without its detractors. Importantly, many experts say the diet is largely unproven, and any benefit is likely the result of a general improvement in eating habits.
Candida is a genus of yeasts that normally live inside the body and on the skin. There are hundreds of these yeasts, but many species can cause fungal infections if their numbers grow out of control or if they enter the bloodstream or other organs. [ 1 ] This type of infection is called candidiasis.
Candida albicans is the species of yeast that most commonly causes candidiasis infection. The overgrowth can result in conditions like oral thrush and vaginal yeast infections. [ 2 ] [ 3 ]
Candida overgrowth is a term that means the yeast is present in such excessive amounts that it becomes pathogenic, says Ali Miller, RD, CDCES, a functional medicine dietitian in Houston and the author of The Anti-Anxiety Diet. As mentioned, candida overgrowth can cause thrush as well as vaginal yeast infections, but some experts, like Miller, recognize candida overgrowth (or imbalance of yeast in the body) as the source of a number of health symptoms that can be overcome with dietary changes.
If you have a yeast infection, you may notice itching and irritation in the vagina and vulva, burning while you pee or during sex, redness in the area, or a cottage cheese–like discharge. [ 3 ] Oral thrush, which can occur in adults and kids, appears as a white coating on your tongue or cheeks, as well as redness and soreness in your mouth. [ 2 ] An invasive candidiasis (fungal infection of the blood or organs) can cause a fever or chills, and it can be life-threatening.
There’s another category, which may be referred to as candida overgrowth, and some healthcare practitioners say it may be responsible for more chronic and seemingly unrelated problems. “Symptoms of candidiasis can be widespread, from bloating and distention to bowel irregularities, chronic fatigue, cystic acne and other skin rashes, and brain fog,” says Miller.
If you’re talking about a vaginal yeast infection specifically, risk factors include a recent course of antibiotics, uncontrolled diabetes, being immunocompromised, and increased estrogen levels (such as in pregnancy). [ 3 ]
In terms of candida overgrowth in general, antibiotic use is by far one of the most common causes, says Miller. “Antibiotics are sterilizing to the microbiome,” or the collection of bacteria and other microbes in the gut, she says. Along with killing off “bad” bacteria, the good bacteria go too, and that can throw off the balance of yeast in your body as well.
Miller mentions that medicines like nonsteroidal anti-inflammatory drugs (NSAIDs) or cortisone-type drugs (like prednisone) can impact the gut microbiome in unhealthy ways. [ 4 ] Lifestyle factors like high stress or high alcohol intake may also make you more susceptible to an overgrowth of yeast, says Miller. That said, hard research on this association is lacking.
The candida diet, generally speaking, removes all sources of flour, sugar, and yeast from your diet and encourages lean proteins, nonstarchy vegetables, and healthy fats, as well as several supplements to encourage the process. Doing so staves off yeast overgrowth, says Miller. “It’s also important to use compounds [through food and supplements] that support the die-off of yeast and the removal of this yeast and its by-products out of the body,” she says.
But it’s important to note that many experts disagree with the idea that this diet is necessary in the first place. “Research in this area is pretty sparse, and even though it often gets blamed for a lot of things, we don’t really know what causes candida overgrowth and whether [the candida diet] even works,” says Abbey Sharp, RD, a blogger and YouTube creator at Abbey’s Kitchen, who is based in the Toronto area. “Currently, no research has been able to definitively support the use of a low-sugar diet to treat candida overgrowth,” she adds. Sharp points to a past review that showed that certain carbohydrates or sugars may promote yeast growth, but more definitive research is needed. [ 5 ]
Another limitation is that the completed research has been largely done in vitro (test tube), which can’t replace human studies. The way organisms behave in a test tube is not necessarily the same as how they behave in the human body.
One perspective paper has offered initial promise, noting that the gut microbiome is an important player in health (as has been well established) and that candida, an “opportunistic” pathogen in the GI tract, can likely also affect digestion and immunity, though more research is needed to understand exactly how. [ 6 ]
The authors also pointed to research that suggests diet may be a valid treatment. A pilot study on 120 patients with chronic intestinal candida overgrowth found that a group that was treated with antifungal medication and who followed a specific diet (one with no simple sugars, alcohol, cured and fatty meats, or dairy) during and after treatment were more likely to have normalized candida levels three months later than individuals who used the medication only. [ 7 ] The researchers wrote that there was no established diet to treat the condition, but the study results were “encouraging.”
You’ll want to check with your doctor before you try any type of cleanse — or any strict diet, for that matter. This one is essentially a temporary, carb-restricted diet. “Think of it as a thorough reset to your microbiome,” says Miller. She generally recommends six weeks for a candida cleanse and suggests eating a maximum of 60 grams (g) of total carbs per day. “Avoid flour-based foods, grains, and sweeteners, and limit fruit and starchy vegetables to two total [servings] per day,” says Miller. The diet emphasizes lean protein, healthy fats, and leafy and cruciferous vegetables. Not only is this diet designed to weaken yeast overgrowth, but it may also help regulate blood sugar because it limits foods that spike blood sugar in the body. “That’s the environment yeast thrives in,” says Miller. The diet is not radical, and it’s safe for most people, except for pregnant and breastfeeding moms, says Miller. In general, experts advise people with a history of disordered eating to avoid restrictive diets as well. “Also, if you have diabetes and are on an oral hypoglycemic drug or using insulin, you will likely need to reduce medication when shifting to a low-carbohydrate diet,” she says. Talk to your healthcare provider. One thing you may notice is that you may feel worse before you feel better: nausea, headache, flu-like symptoms, and fatigue may appear within the first two weeks of the cleanse. This typically will not last for the entirety of the six-week cleanse. Proponents of the diet say this is a natural part of cleansing, but it’s important to take symptoms like this seriously since the protocol is largely unproven. Keep in mind that what may actually be happening is a phenomenon called the “keto flu,” which can occur as the body switches from a state of burning carbohydrates for fuel to burning fat. “When we reach a state of ketosis, we often experience a few weeks of keto flu symptoms, like foggy head, headache, and fatigue. Limiting carbs on a low-sugar candida diet has the potential to trigger ketosis and the associated symptoms,” says Sharp. It’s also important to note that there isn’t much scientific evidence that cleansing the body in general is necessary or helpful.
