Zinc – A Surprising Treatment for Vaginal Yeast Infections

By revealing fresh light on how bacteria in the body absorb zinc, this research could one day pave the path for the treatment of vaginal yeast infections.

Roughly three-quarters of women may acquire vaginal yeast infections at some point in their lives, and roughly 140 million women worldwide will experience recurrent infections. Recurrent yeast infections can have a significant influence on one’s quality of life. Existing antifungal therapies are not always successful, and resistance to these medications is growing.

Candida is the yeast that causes thrush. Candida albicans is the most common Candida species, causing the majority of yeast infections.

A recent study lead by the University of Exeter’s MRC Center for Medical Mycology has discovered that the trace mineral zinc may play an unexpected function. Candida albicans, like us, requires zinc in its diet, and this yeast creates a molecule (Pra1) that attempts to scavenge zinc as a food source. Researchers have discovered that this chemical causes an inflammatory reaction, which they believe is the cause of many occurrences of thrush.

The study, titled “Zinc prevents vaginal candidiasis by inhibiting expression of an inflammatory fungal protein,” was published in the journal Science Translational Medicine.

Welcome Trust Senior Fellow Dr. Duncan Wilson, of the University of Exeter’s MRC Center for Medical Mycology, led the research, and said, “Recurring thrush can be deeply distressing and problematic, and we urgently need new treatments. Our new finding on zinc is very exciting, because it suggests that simple provision of zinc could block the production of the inflammatory Pra1 molecule, but we’re not in the position to make treatment recommendations at this stage.”

“We need larger-scale trials to confirm the effect. Please don’t apply any products that are not designed for the genital area, as zinc can be toxic at high concentrations and it could be extremely unsafe.”

The scientists discovered that altering genes so that Candida albicans does not release Pra1 decreased inflammation in lab trials. They discovered that giving mice relatively low levels of zinc reduced Pra1 synthesis and avoided inflammation. This is significant because the burning and itching symptoms of thrush are caused by inflammation.

The researchers also sought women who had vaginal infections at least once per three months. The women used a vaginal moisturizing cream containing a trace of zinc nightly for two weeks, then twice a week. Five of the six women who finished the research and had vulvovaginal candidiasis (thrush) did not have reinfection over the three-month period.

Dr. Wilson said, “These findings are very encouraging, although the number of participants is small. We are now carrying out a larger clinical trial to confirm that zinc treatments are effective. In the longer term, we hope this could be a promising strategy for a condition could evolve resistance to treatment.”

“We’d been studying this Pra1 molecule for more than ten years to understand its role in zinc scavenging—this research shows the fundamental importance of basic research of this nature, which can help shed light on how our bodies work and sometimes provide surprising routes to new treatments.”

For more information: Elena Roselletti et al, Zinc prevents vaginal candidiasis by inhibiting expression of an inflammatory fungal protein, Science Translational Medicine (2023).

DOI: 10.1126/scitranslmed.adi3363.