Probiotics is a collective term for microorganisms - such as those found in fermented dairy products and fermented veggies such as kimchi and sauerkraut - that are believed to be beneficial to the body, especially the bacterial flora of the digestive system. The notion that probiotics are good for you dates back to the early 1900s when it was first proposed that eating yogurt can increase longevity, thanks to its high content of lactic acid bacteria (lactobacillus). Today, probiotic supplements and food products have grown into a $40 billion market.
Many supplements target the digestive system, and promise that improving the gut flora will benefit the body in general. But probiotics also are branded as effective against everything from allergies and high cholesterol, to asthma and urinary tract infections. In fact, to date, scientific evidence supporting these claims is lacking. They haven’t been conclusively disproven either, but there just isn’t any proof that probiotics are very effective against illness. The only ailment where probiotics have been scientifially proven to be of benefit, is diarrhea. Even then, probiotics will not help with many types of diarrhea.
I general, probiotics rarely cause adverse effects and are safe to take, even for children. While we may well find that they are beneficial in the treatment or support of other conditions, our current understanding of probiotics, the gut flora and the effect they may have on general health, is actually quite poor.
This question is still hotly debated in the medical community. There are a number of small-scale studies that suggest that probiotics can work against BV and possibly stop it from recurring. However, even the authors of these studies concede that larger clinical trials are needed to arrive at a definite conclusion.
Since BV is caused by an imbalance of bacteria in the vagina, treating BV with probiotics makes sense in theory. When BV develops, bad bacteria is growing faster and colonizing more space than good bacteria (like the lactobacillus genus). By introducing more lactobacillus into your vagina, you are helping the good bacteria gain the upper hand and restore equilibrium. You can directly insert the probiotics into the vagina as suppository capsules or natural yoghurt cultures. Taking oral probiotic supplements is less effective, as it they have to survive your digestive system and find a way into the vaginal canal. Direct vaginal application seems like the faster and better route.
The specific lactobacillus types in most probiotics are L. rhamnosus and L. acidophilus, because these are the most common species in your digestive tract. In the vagina however, L. crispatus and L. iners are the predominant beneficial strains.
Another problem is that probiotics, like most supplements, aren’t regulated by the FDA or subject to specific standards. No one organization scrutinzes these supplements and tests them to determine if they really contain what they promise on the packaging. In fact, independent tests have found that frequently, they don’t contain what they claim to, or at least not in the promised quantities.
There is hope however, for women troubled by recurring BV. L. crispatus is a vaginally inserted medication in the last stages of clinical trials, and is one of several treatments in development that show promise. Another option that’s currently in trials, is vaginal microbiota transplantation, which means good bacteria are transplanted from a healthy donor into the vagina of a recipient affected by BV.
The story here is very similar to BV. Yeast infections are caused by uncontrolled growth of a vaginal fungus (candida albicans) when the yeast cannot be counterbalance or repelled by good bacteria. Typically, yeast infections may occur following a course of antibiotics, which can deplete both good and bad bacteria. Individuals with diabetes are also prone to yeast infections, as high blood sugar feeds the growth of yeast, which then overwhelms the good bacteria in the vagina. Probiotic treatment in this case serves the same ends as with BV; introducing more good bacteria to rebalance vaginal flora.
Conclusive research on the success of probiotics is lacking. Studies tend to be small in size and poorly controlled. As women frequently take probiotics while also taking conventional antifungals, it is not often clear how much the probiotics are actually doing.
Since there aren’t any side effects, you can always give it a try. Avoid oral probiotics and use vaginal applications (suppositories or live yogurt) which should be more effective.
UTIs are more difficult to treat than BV and yeast infections, as the bacteria sit deeper inside the body. A simple UTI can affect the urethra and bladder, while a more complicated infection can involve the kidneys and require hospitalization. External probiotic applications to the outer vagina will be of little use in this case. There’s also no good evidence that oral probiotics can cure or prevent a UTI. There have been several studies over the past 20 years, often of poor scientific value. Results thus far have been disppointing but not definitive.
Current scientific consensus doesn’t see much harm in taking probiotics. So, while they should not be used alone to treat a UTI, they can be used as a complement to antibiotics.