Bacterial vaginosis is a frequent, difficult-to-treat female disorder caused by an imbalance in the vaginal microbiota and characterized by a decrease in lactobacilli and an increase in potentially harmful bacteria, especially Gardnerella vaginalis. Despite antibiotic treatment, around 60% of affected women will relapse within the following year.
Change of method
Since a link between blood levels of some nutrients and the risk of bacterial vaginosis is suspected, many studies have been conducted but their results have been inconsistent. The authors of a new study published in Reproductive Health believe it is due to the methods used in these studies which are based on vaginal swabs or clinical endpoints and mainly focused on vitamin D. To examine the association between the use of dietary supplements and bacterial vaginosis, they analyzed the composition of the vaginal microbiota of 104 young women, including 25% with bacterial vaginosis. They also analyzed their daily intake on micro- and macronutrients based on their answers to a benchmark questionnaire. The researchers also reviewed the scientific literature on this topic.
Higher betaine intake?
They managed to profile women with vaginosis: such women use more frequently vaginal douches, have a high body mass index, and less often use a hormonal method of contraception, compared to women with a balanced vaginal microbiota. Overall, those with lower nutrient intakes have a lower risk of vaginosis. However, betaine is the one exception since a limited intake increases the risk. In vitro, this substance seems to stimulate the survival of lactobacilli and the production of lactic acid, and to prevent colonization by pathogens. According to the authors, it acts directly on the vaginal microbiota by promoting bacterial balance or indirectly through the gut microbiota. This discovery opens up new perspectives to limit the risk of vaginosis, such as increasing betaine intake by changing diet or using dietary supplements.