Fungal Infections (Candida)
Nutritional Therapy for Candida Infections
Given the rise in candida infections (Hsu 2011), and their increasing resistance against commonly used antifungal drugs (Pfaller 2012), novel therapies for the prevention and management of these infections are needed (Mailander-Sanchez 2012).
Dietary modifications such as limiting intake of refined carbohydrates (e.g., pasta, bread, sweets, soft drinks, etc.) may be helpful for people with candida infections. Higher dietary sugar is associated with vulvovaginal candidiasis and abnormal glucose metabolism is associated with recurring vulvovaginal infections (Donders 2010). Diets rich in carbohydrates are also associated with candida overgrowth in the gastrointestinal tract and may contribute to mucosal invasion (Weig 1999; Akpan 2002). Laboratory studies indicate that excess glucose weakens the immune system’s response to candida as well as the azole class of antifungal drugs (Rodaki 2009). Candidiasis patients should maintain a healthy, well-balanced diet, as poor nutrition is a commonly overlooked risk factor for bacterial and fungal infections (Curtis 2010). More information about blood sugar control is available in the Diabetes protocol.
Probiotics – Data suggest that probiotics such as lactobacillus are beneficial against mucosal candida infections (Mailander-Sanchez 2012), and should be especially considered for women who suffer from more than three yeast infections per year (Falagas 2006). Research shows that probiotics exert their beneficial actions by suppressing the growth of candida (in various regions of the body) and inhibiting candida’s ability to adhere to cell surfaces (Balish 1998).
Dietary products containing probiotic bacteria (e.g., certain cheeses and yogurts) can help control candida growth in the human body (Hatakka 2007; Williams 2002). In a study, yogurt containing lactobacillus was associated with a decreased amount of vaginal yeast (detected by culture), as well as a reduced rate of vaginal discharge associated with yeast infections (Martinez 2009).
While yogurt has long been considered a favorite natural remedy for vaginal candidiasis, and has been shown to suppress Candida albicans growth (Williams 2002; Hamad 2006), women must carefully choose yogurt products that are low in sugar. Supplemental probiotics containing lactobacillus, administered either orally or vaginally, can also help resolve urogenital infections (including yeast infections) (Reid 2001; Abdelmonem 2012). In particular, the lactobacillus species rhamnosus and reuteri have been studied for repopulating vaginal flora and reducing yeast populations (Reid 2003; Reid 2009).
Probiotics may also be useful after a course of antibiotics. Antibiotics used to kill pathogenic bacteria also destroy the beneficial bacterial flora of the vagina, putting women at risk to develop yeast infections (Donders 2010). Probiotics also help re-balance gut bacteria, and thus may help avoid symptoms of leaky gut syndrome (Horne 2006).
Resveratrol – Resveratrol, a compound found in the skin of grapes, may contribute to the anti-inflammatory characteristics of red wine. In 2007, researchers investigated (in a laboratory) the fungicidal activity of resveratrol against Candida albicans. They concluded that resveratrol demonstrated potent antifungal properties, and appears to be safer than conventional antifungal drugs such as amphotericin B (Jung 2007). In 2010, further research revealed that resveratrol impairs the ability of Candida albicans to convert into its more infectious form, and thus may be a useful agent against candida infections. In fact, resveratrol’s chemical structure may form the foundation of an entirely new class of antifungal drugs (Okamoto-Shibayama 2010).
Goldenseal – Goldenseal (Hydrastis canadensis L.) is a botanical that has been used to fight inflammation and infection. An active ingredient in goldenseal is berberine (Ettefagh 2011), which has been shown to have strong antifungal effects against candida in a laboratory setting (Liu 2011). Berberine has also demonstrated synergistic effects against Candida albicans when used in combination with commonly used antifungal drugs (e.g., fluconazole) in laboratory studies (Wei 2011; Iwazaki 2010; Xu 2009). Berberine may combat candida growth by interfering with the ability of the fungus to penetrate and adhere to host cells (Yordanov 2008). Study outcomes have been so positive that, similar to the case with resveratrol, synthetic analogs of berberine are being developed that may represent a new class of antifungal medications (Park 2006; Park 2010).
Although berberine has been studied in human clinical trials and shown to have several metabolic benefits, concerns about long-term use of berberine have been raised on the basis of certain preclinical studies (Kysenius 2014; Mikes 1985; Mikes 1983). Some evidence suggests that long-term berberine use, especially at high doses, may impair particular aspects of cellular metabolism in specific types of cells. The implications of this preclinical research are yet to be determined by long-term human clinical trials, therefore Life Extension currently recommends short-term use of berberine.
Lactoferrin – Lactoferrin, a protein found in mucosal secretions (e.g., human colostrum/milk, tears, saliva, and seminal fluid) (Haney 2012; Andrés 2008; Venkatesh 2008), possesses broad-spectrum antimicrobial activity against bacteria, fungi, viruses, and protozoa (Kobayashi 2011). Lactoferrin demonstrates a significant antifungal effect against a variety of pathogenic candida species (i.e., Candida albicans, Candida krusei and Candida tropicalis) (Al-Sheikh 2009). In addition to lactoferrin’s ability to interfere with candida growth on its own, it also displays potent synergism with common antifungal drugs; it has been shown to enhance the antifungal activity of fluconazole against candida (Kobayashi 2011). Although lactoferrin’s antifungal activity against Candida albicans has been well established, the mechanism by which it achieves this effect is not as clear (Andrés 2008). Lactoferrin’s ability to bind to iron may contribute to its antifungal activity (Yen 2011), especially since iron appears to enhance the proliferation of candida species (Al-Sheikh 2009).
Lactoferrin derived from both bovine and human sources inhibits growth of oral candida (Venkatesh 2008). However, bovine derived lactoferrin has been specifically identified as a promising treatment option for oropharyngeal candidiasis (Yamaguchi 2004).
Tea Tree Oil – Tea tree oil is an essential oil derived from leaves of the native Australian plant Melaleuca alternifolia (M. alternifolia). It is well known for its medicinal value and has been used by Australian Aborigines to treat colds, sore throats, skin infections, and insect bites (Larson 2012; Warnke 2009). Tea tree oil has a variety of therapeutic properties (e.g., anti-inflammatory and antiseptic) and is a popular ingredient in a number of natural cosmetic products (e.g., shampoo, massage oil, and skin/nail cream) (Larson 2012; Catalán 2008; Mondello 2006). Tea tree oil, capable of eliminating a large number of microorganisms (Catalán 2008), shows promise as a treatment for candida infections (Willcox 2005). Animal studies indicate that one of the active compounds in tea tree oil, terpinen-4-ol, may be especially promising for treating drug-resistant forms of vaginal candidiasis (Mondello 2006). Furthermore, tea tree oil may have beneficial effects against fluconazole-resistant oropharyngeal candidiasis (Wilcox 2005).
Laboratory research indicates that tea tree oil may exert its yeast-killing effect by inhibiting candida’s ability to replicate. It also appears to interfere with membrane properties/functions of candida (Catalán 2008). In addition, research has demonstrated tea tree oil reduces candida’s ability to adhere to human cell surfaces (Sudjana 2012).
Although tea tree oil is occasionally associated with contact dermatitis (when used topically), it is generally considered to be safe. However, it can be toxic when ingested orally, producing a variety of negative effects (e.g., vomiting, diarrhea, and hallucinations) (Larson 2012). Therefore, it is typically used topically and should be kept out of the reach of young children.
Other Essential Oils – Essential oils (i.e., volatile oils) refer to the compounds found within aromatic plants that give them a particular odor or scent (NIH 2012). Most essential oils are a mixture of various chemicals, which are of clinical interest due to their large spectrum of biological activities (de Araujo 2011).
Although tea tree oil is considered one of the most important essential oils for biological activity against candida (Mondello 2006), a wide variety of essential oils possess anti-candida properties (e.g., carvacrol, 1,8-cineole, geraniol, germacrene-D, limonene, linalool, menthol, and thymol) (Azimi 2011). Experimental models involving geranium oil (or its main component geraniol) show that it suppressed candida cell growth (Maruyama 2008). In addition, clove oil and its major constituent eugenol have shown particularly potent effects against candida (Nozaki 2010), and may be effective against multi-drug resistant forms of Candida albicans alone or in combination with other common antifungal drugs (e.g., fluconazole or amphotericin B) (Khan 2012). A laboratory study demonstrated that essential oil from Moroccan thyme may act synergistically with common antifungal drugs, potentially reducing the need for high doses, which may in turn minimize associated side effects and treatment expenses (Saad 2010). Research has also identified the essential oil of Lemon Verbena (Aloysia triphylla) as a promising alternative for the treatment of candidiasis (Oliva Mde 2011). Compounds isolated from the essential oil of oregano possess antifungal activity as well (Rao 2010).
Garlic – For centuries, the garlic plant Allium sativum has been used as a popular food, spice, and herbal remedy (Aviello 2009; Dini 2011). Garlic has been noted to possess cardiovascular (Ginter 2010), anticancer, antioxidant, and antimicrobial benefits (Dini 2011). Garlic (and its constituent allicin) can cause potent growth inhibition in yeast and be effective against mucosal and systemic/invasive candidiasis (Chung 2007; Low 2008). Research suggests that allicin, due to its effect on reducing the growth of biofilm (a component of candida allowing it to become resistant to certain antifungal agents), may reduce candida’s ability to become resistant to common antifungal drugs. Allicin may also decrease the production of candida by disrupting its membrane (Khodavandi 2011). A clinical trial found that the topical administration of a garlic paste was as effective at suppressing the symptoms of oral candidiasis as clotrimazole solution (the conventional antifungal treatment for this indication) (Sabitha 2005). Likewise, a clinical study of candida vaginitis concluded that there was no difference in treatment response between a vaginal cream containing garlic & thyme, and a vaginal cream containing clotrimazole (Bahadoran 2010).
Additional Alternative Therapies
AHCC – Active Hexose Correlated Compound (AHCC) is an extract derived from fungi of the Basidiomycetes family. AHCC has demonstrated biological activity against a variety of disorders (NIH 2012). Experimental research has shown that AHCC appears to have a protective effect against candida infections, especially among the immunocompromised (Ikeda 2003). Likewise, a 2008 experimental study suggested that supplementation with AHCC may increase the survival of hosts acutely infected with a variety of pathogens such as Candida albicans (Ritz 2008). Additional therapies to support a healthy immune system can be found in the Immune System Strengthening protocol.
Caprylic Acid – Caprylic acid (i.e., octanoic acid) is commonly available as a non-prescription agent that is well known for its anti-bacterial and anti-fungal properties (Omura 2011).
Boric Acid – Boric acid (i.e., boracic acid or orthoboric acid) is the most common form of the mineral boron, which is often used as a supplement for building strong bones and muscles as well as supporting cognitive function and muscle coordination (NIH 2012; Iavazzo 2011). Boric acid has also been shown to inhibit the growth and reproduction of fungi (i.e., fungistatic action) (Iavazzo 2011), and is used intra-vaginally to treat yeast infections (NIH 2012; Spence 2007). In fact, a 2011 review article concluded that boric acid may be recommended as a safe, effective, and relatively cheap treatment for recurrent yeast infections (Iavazzo 2011). Boric acid has also been proven to be efficient for the treatment of most yeast infections that are resistant to conventional therapies (Donders 2010), and thus may be considered a second-line alternative treatment option for this indication (das Neves 2008).