How vegetarians bad-mouth themselves!

Last Updated on June 5, 2019 by Afifah Hamilton
Read Time: 3 min

Vegetarians have more oral candida species – and they’re the highly pathogenic kind

Candida albicans is the yeast that causes thrush when it gets out of control and can even become life threatening in immunocompromised patients. Despite this, Candida albicans is a commensal, meaning it is part of the natural flora found in and on humans – so many people have it, for example, in their oral cavities where for the most part it doesn’t cause any trouble. In recent years, however, new pathogenic species of Candida have been on the rise. These species are particularly resistant to anti-fungal treatment and cause more life threatening conditions so are an increasing cause for concern.


A recent study carried out by Indian researchers took mouth swabs from 238 participants to identify oral candida species and cross referenced this with the participants’ habitual diets.

Prevalence of Candida species in vegetarians and non-vegetarians, Shankargouda Patil et al, J Clin Diagn Res. (Jul 2017)

They found that

  1. Candida species were present in the oral cavities of 69% of vegetarians but only 41% of non-vegetarians;
  2. There was a much higher incidence of the new Non-C. albicans species among the vegetarians, whilst the familiar C. albicans was more common among non-vegetarians (see table above)
  3. Vegetarians were more likely to have multiple species, whereas non-vegetarians predominately just had the common commensal C albicans.

Having these species in the oral cavity does not mean they will automatically lead to disease, because these organisms are opportunistic: they only become pathogenic when they get into the bloodstream of an immunocompromised patient, or are inadvertantly introduced during surgery. This could happen during a routine operation, dental surgery or following a serious infection and treatment, or conditions leading to immunocompromise such as leukaemia. Chronic mucocutaneous candidiasis is relatively common, however, and refers to a range of recurrent or persistent conditions where Candida species infect the gums, nails or skin (think fungal toe nails). Occasionally such infections become systemic but in the past 20 years these more deadly species have become significant.

Disease patterns of the non-albicans Candida species

  • C. tropicalis
    Is considered the most prevalent pathogenic non-albicans yeast. As an opportunistic pathogen it can affect newborns and immunocompromised patients. If it (or other non-albican species of Candida) gets a foothold in post-operative patients there is a 30-100% mortality rate. Morbidity and mortality rates due to C. tropicalis infection are higher than C. albicans infection. (R. J. Kothavade et al, Journal of Medical Microbiology, 2010)
  • C. glabrata
    Is relatively difficult to diagnose, and is a leading cause of bloodstream infections in hospitals with a 48% mortality rate. Worryingly, it is considerably resistant to standard anti-fungal treatment. (N. Foster et al, Journal of medical microbiology, 2007)
  • C. krusei
    A multi-drug resistant hospital aquired pathogen. Has been identified in cases of vaginal candidiasis, gastrointestinal diseases and systemic blood infections in immunocompromised patients.

The findings of this study suggest that we would expect vegetarians to be more at risk of these infections, but also, more likely to be vectors, spreading such infections.

If you have to have surgery just hope your surgeon is not vegetarian!

Presumably the most significant actions one could take to avoid these scenarios would be the following: 1) Do not be vegetarian  2) Avoid vegetarians 3) Ensure your diet is generally low in carbohydrates (which are the main dietary fuel for all yeasts) and 4), Eat plenty of coconut oil, which has some anti yeast properties, including using this oil as a mouth wash (which is termed ‘oil pulling’).


5 thoughts on “How vegetarians bad-mouth themselves!”

  1. But vegetarians have 0 candida krusei per the report you quote. Krusei is far more serious. I’m not a veggie…though I used to be:
    PUB MED: Candida krusei fungemia. An escalating serious infection in immunocompromised patients.
    Abbas J1, Bodey GP, Hanna HA, Mardani M, Girgawy E, Abi-Said D, Whimbey E, Hachem R, Raad I.
    Author information
    Candida krusei is inherently resistant to fluconazole and is emerging as a frequent cause of fungemia in patients with hematologic malignant neoplasms.
    To determine the risk and prognostic factors associated with C krusei fungemia in comparison with Candida albicans fungemia in patients with cancer.
    Retrospective study of 57 cases of C krusei fungemia occurring at the M. D. Anderson Cancer Center, Houston, Tex, from 1989 to 1996. The C krusei cases were compared with 57 cases of C albicans fungemia with respect to demographics, underlying cancer, Acute Physiology and Chronic Health Evaluation II score, immunosuppression status, chemotherapy, and the use of central venous catheters, as well as fluconazole prophylaxis.
    At our institution, C krusei accounted for 5% of fungemias during 1989 through 1992 and for 10% during 1993 through 1996. Patients with C krusei fungemia more often had leukemia than patients with C albicans (77% vs 11%; P =.02), whereas catheter-related infections were more common among patients with C albicans fungemia (42% vs 0%; P<.001). Patients with C krusei fungemia had a lower response rate (51% vs 69%; P =.05), largely because they more frequently were neutropenic and had disseminated infection. Mortality related to fungemia was 49% in the cases with C krusei vs 28% in C albicans. Multiple logistic regression analysis showed that persistent neutropenia (P =.02) and septic shock (P =.002) were predictors of poor prognosis.
    In neutropenic patients, C krusei fungemia is associated with high mortality. It should be suspected in patients with leukemia who are receiving fluconazole prophylaxis and should be treated aggressively with an amphotericin B regimen.
    ps i wouldn't agree with the treatment regimen above!!!

    • I think you misread the table: 0 cases were in non vegetarians (middle row), There were 5 cases found in the vegetarian group (top row), which was about 5% of those tested.
      Yes, these bugs are awful if you get them as systemic hospital acquired infections.

      • Thanks for your reply.
        Do you think its possible that Lichen Sclerosus is caused by systemic candida? Or another fungus, parasite or virus such as Epstein Barr?

  2. Thanks yes I did misread…its the highest infection rate in non vegetarians with candida albicans, you propose that its a commensal…but could it be an overgrowth?

  3. There is no mention in the study of dairy consumption, with the difference between the non-vegetarian and vegetarian groups being consumption of meat. A vegetarian diet in India (where I lived many years) is practically always lacto-vegetarian – with meat being replaced by dairy. Here is some basic info: “Due primarily to religious restrictions, vegetarianism is widespread in India. But very few Indians follow a vegan diet in which all animal products are avoided. Milk and other dairy products, derived from both cows and water buffalos, are avidly consumed across a large portion of the country. Indeed, India is the largest milk producer in the world by a good margin (…)” ( So the study may well be about increased prevalence of candida linked to increased consumption of dairy. And of course the study states that “C. albicans was the most common species to be isolated in both vegetarians (35.1%) and non-vegetarians (39.2%)”.


Leave a Reply