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CHAPTER 7

Food and Vaginal Health

THERE IS AN ONGOING MYTH that food has a direct impact on vaginal health. Over the past twenty-five years, I have been interviewed by multiple reporters on this subject. Many times, I gave a detailed account of why a direct gut-vagina connection is biologically impossible, yet headlines such as “Eat Pineapple for a Sweeter Vagina!” or “Banish Yeast by Ditching Bread!” always appeared. It seems the truth, “Your Vagina Just Wants You to Eat a Healthy, Balanced Diet!” isn’t sexy enough.

What’s the harm, you say?

This supposed direct connection between food and the vagina is a complete misunderstanding of how the body works, and facts matter. In addition, the idea of eating food to change the way a vagina smells supports the tired and destructive trope that there is something wrong with a normal, healthy vagina. It’s simply a different spin on douches.

The other issue with vaginal food fallacies is that they can lead to severe dietary hypervigilance and restrictions—essentially, vaginal orthorexia (orthorexia is an eating disorder with extreme attention to foods perceived as healthy and avoidance of foods believed to be harmful). I have lost track of the number of women who have told me they haven’t had a slice of cake or a cookie for years, trying to rid themselves of yeast, and yet they still have their same symptoms. The exasperation in these voices is not insignificant. And really, having a slice or cake or a cookie now and then is nice.

If you have a concerning vaginal odor, you should read chapter 43 and see a doctor or nurse practitioner—the remedy is most definitely not at the grocery store.

Can Fruit Change the Smell of My Vagina?

Vaginal discharge is a combination of epithelial cells from the vaginal walls, breakdown products made by healthy vaginal bacteria (lactobacilli), cervical mucus, and a small amount of transudate (fluid that leaks out between cells). See chapter 2 for a review. The biggest contributors to vaginal scent are substances produced by the lactobacilli, just as body odor is related to skin bacteria breaking down products made by specialized sweat glands.

Food will not kill lactobacilli, make it reproduce, or change the products of lactobacilli metabolism. For food to rapidly change vaginal odor in an eat-this-then-smell-like-that kind of phenomenon, a volatile substance (meaning something that can evaporate and produce a smell) would have to survive digestion or be created by digestion and then make it to the vagina. As only the tiniest bit of fluid from the bloodstream even makes it into the vagina, this would have to be a very potent substance. It would also have to somehow not affect body odor or the smell of urine.

Basically, magic would be required for a food to change the scent of a vagina.

What About Garlic and Asparagus?

There are a few volatile metabolites from food that are known to impact body odors. They have pungent or musty smells, so not sweet or desirable. The best-known example is the smell of urine after eating asparagus. While the actual mechanism is still not known, most researchers think some people metabolize asparagusic acid from asparagus into a sulfur smelling compound that is excreted in the urine. Approximately 40 percent or so of people can smell these unpleasant metabolites. The reason some people can detect the smell as nasty and others cannot may be genetic. Garlic also has volatile metabolites, described as having a garlic-and /or cabbage-like odor, that have been detected in urine and in breast milk. Kidneys and breast tissue actively concentrate certain metabolites, so it makes sense that if you eat enough garlic, a malodorous metabolite could be concentrated in urine or breast milk and impact smell.

The vagina does not concentrate metabolites.

The Sugar-Yeast Connection

There is a relationship between blood sugar and infections, but eating foods high in sugar does not directly impact the vagina.

As we discussed in chapter 2—but it’s worth another mention—up to 3 percent of the vaginal fluid is glycogen, a storage sugar. There is also glucose as well. The amount of glycogen and sugar varies depending on the phase of the menstrual cycle, but at times it can be found in a higher percentage than blood.

It is not possible to change the sugar level in your vagina through diet, as the sugar comes from the mucosal (skin) cells. Researchers actually attempted to increase the storage sugar in the mucosal cells by having women eat more carbohydrates, and it was ineffective. In another study, women ingested a load of sugar, equivalent to guzzling two cans of cola, and researchers found sugar levels did not increase in the blood or in the vagina, not even for women with a history of yeast infections.

Your vagina needs sugar, and the levels in your vagina have nothing to do with food.

Yeast infections are a major issue in the intensive care unit. We all have yeast in our bowel, vagina, and on our skin, so when we have invasive procedures that break the skin barrier, the normal, minding-its-own-business yeast can now enter the bloodstream. This is a systemic yeast infection, and it is very serious. Without intravenous therapy, it is fatal. Researchers have looked at diets and nutritional supplements for people in the intensive care unit to try to reduce yeast colonization in an attempt to reduce these serious yeast infections, and to date they have all failed. If diet could reduce yeast colonization, we would already know. A doctor selling a special diet and supplements who has never published research in the area does not have the secret answer to the question of how to reduce yeast colonization. The idea of an anti-candida diet is simply not supported by basic biology or the available research.

There are studies that indicate women with diabetes (a condition associated with higher blood sugars) are more likely to have yeast in the vagina, and that yeast is more likely to overgrow and cause infections. It is also true that this is complex, and the reasons are not fully understood. Recently, data has emerged that points to increased glucose in the urine as the cause. When blood sugar levels are high, excess sugar literally spills into the urine. When women empty their bladders, there is a microscopic mist of urine that gets on the skin. While the vagina evolved to tolerate sugar, the skin of the vulva has not, and glucose exposure here can favor the growth of yeast, leading to vulvar yeast infections. Some of that yeast may make it into the vagina, leading to a vaginal infection.

This theory is supported by a safety alert from the Food and Drug Administration (FDA) regarding a serious infection of the genitals (necrotizing fasciitis, also known as the flesh-eating bacteria) associated with a class of medications called sodium-glucose cotransporter 2 (SGLT2) inhibitors. This includes canagliflozin, dapagliflozin, and empagliflozin. The medication is used to lower blood sugar for people who have type 2 diabetes, and it works by helping the kidneys remove more sugar. This could lead to increased glucose on the skin that could favor the growth of pathogenic (harmful) bacteria.

Elevated blood sugars may also impact the way the immune system responds to infections or even the healthy bacteria that helps to keep infections at bay.

So you have read all this, and you are not convinced about the lack of dietary connection between sugar and yeast in the vagina (for women who do not have diabetes) because you feel that you get vaginal symptoms every time you eat sugar.

The answer is what is called a “nocebo effect,” which is a negative effect on health due to negative expectations (basically an unpleasant placebo response). It is the result of conditioning, specifically the belief that something negative will happen. This doesn’t mean someone with symptoms of irritation after eating sugar is faking or that their symptoms are not real. There are real chemical changes in the brain producing the itch or irritation, but the cause of those changes is a negative expectation, not sugar. Nocebo effects are well studied. Every drug trial that has one group take a placebo, an inert sugar pill, has at least 2–5 percent of people who discontinue the placebo due to serious side effects that are perceived to be drug related. As these people didn’t receive an actual medication, their symptoms can only be explained by negative expectations, or nocebo.

Can bread or beer or wine cause yeast infections?

Yeast is used to make wine, beer, and bread, so it is easy to see how the myth of alcohol or bread causing yeast was started. Common sense tells us this can’t be so, as the French have been enjoying fine breads and wine for hundreds of years, and French women are not plagued with yeast infections.

Science backs up the common sense. The yeast most commonly used for bread and alcohol is Saccharomyces cerevisiae, and this is only rarely a cause of vaginal yeast infections (about 1 percent of the time). Sourdough starters scavenge wild yeasts like Saccharomyces exiguus, Candida milleri, and Candida humilis from the environment, which do not cause vaginal yeast infections (they also scavenge S. cerevisiae). If that isn’t enough reassurance, then consider that yeast in bread, wine, and pasteurized or filtered beer is dead. An unfiltered, unpasteurized beer may have some yeast that is dormant—but again, this isn’t the right type.

I understand that a woman claimed to have made bread with a sourdough starter she nourished with her vaginal yeast, and this seems as good a place as any to address this story. First of all, we have no idea if what she grew from her vagina was Candida albicans (the most common cause of yeast infections) or even any type of yeast, for that matter. Belief that you cultured something doesn’t cut it scientifically. The vagina is filled with bacteria, and any swab not cultured appropriately in a lab may grow all kinds of microorganisms, most of which will not be yeast. Second, her sourdough starter, like all sourdough starters, would have scavenged the wild yeast from the air and surface of the flour, etc., and so even if she did manage to grow yeast from her vagina, it would have added nothing to the baking except temporary internet fame—and, of course, more confusion about yeast. The next time you see this story make the rounds on the Internet, please don’t pass it along. Just ignore it.

If you want to prove that vaginal yeast can bake bread, you are going to need to add cultured C. albicans directly to the flour as you would any store-bought yeast, but that seems like a thoroughly unnecessary exercise. So let’s not.

The Best Foods for Vaginas

There are no bad or good foods, as far as the vagina is concerned. I know this upsets a lot of people, but there are really no good or bad foods in general, with the exception of trans fats, which are modified fats linked with inflammation and heart disease. Avoid these for all kinds of health reasons (this means saying goodbye to icing from a can). There are healthy diets and less healthy diets, and eating well is good preventative medicine, but eating a specific food as treatment doesn’t apply to the vagina.

What about cranberry juice for preventing urinary tract or bladder infections? In the early 1900s, before we had modern methods to diagnose bladder infections and before antibiotics, doctors recommended cranberry juice because the hippuric acid that is released as the body metabolizes cranberries makes the urine very acidic. The theory was the acidity would make it harder for bacteria to grow. Cranberries also have a lectin (a protein) that may prevent bacteria from binding to cells in the urinary tract (bacterial adherence to cells is a necessary step in infections). While both of these hypotheses are biologically plausible and worthy of pursuit, multiple studies have looked at cranberry juice and found no benefit. In addition, juice has no nutritional value; it’s just nature’s soda. Cranberry juice, even unsweetened, has a lot of sugar, and some brands can have as much as soda.

Two small studies have linked a high dietary saturated-fat (animal fat, so meats and dairy) intake with bacterial vaginosis, but this is far from a certainty. A high-fat diet could also be a correlation, not a cause, meaning women with these diets are more likely to have other risk factors for bacterial vaginosis. How this connection might exist biologically is simply not known. There are other health reasons besides your vagina to try to avoid a diet that is very high in saturated fat.

Eating at least 25 g of fiber a day is the best preventative health advice I can offer vagina-wise, as fiber is a prebiotic, meaning it feeds good bacteria in the bowel. Fiber also draws water into the stool, softening it and helping it move along more quickly, thereby preventing constipation. Constipation can lead to straining, which can cause pelvic floor spasm (potentially causing pain with sex or pelvic pain) and hemorrhoids. The average American only eats 7–8 g of fiber a day, so I recommend a fiber count, meaning writing everything down that you eat for 1–2 days and then checking the fiber count so you know how much you are eating and can make changes if necessary. I’m a little lazy, so I just eat a cereal with 8–13 g of fiber a serving most days, so I know I’m one third to one half of the way there before I’ve even started my day.

Lots of people ask about fermented foods, such as yogurt, sauerkraut, or kombucha, to help cultivate good gut bacteria. Typically, these foods do not contain the right strains of lactobacilli for vaginal health, although they may have bacteria that is healthy for the gut. Some studies have linked fermented milk products like yogurt with a reduction in bladder cancer, heart disease, gum disease, and cardiovascular disease. Fermentation enhances the nutritional value of vegetables and may increase the iron that is available for absorption. Many women are iron deficient, so this obviously won’t hurt.

It is possible the bacteria in fermented dairy and vegetables could have a beneficial impact on normal gut bacteria after antibiotics, but we don’t have any research on the impact on vaginal health. Having fermented foods if you are on antibiotics is probably not a bad strategy to try to lessen the impact of antibiotics on your gut bacteria (this is a cause of antibiotic-related diarrhea). However, as there are no studies that prove this works, I wouldn’t sweat it if you don’t like fermented foods and that strategy doesn’t appeal to you. Personally, I despise sauerkraut and kombucha, and for me to give them a try there would need to be several very robust studies to show they definitively help protect gut bacteria after antibiotics.

BOTTOM LINE

• Food can’t change the vaginal scent.

• There is no anti-candida diet. If you don’t have diabetes, what you eat is not going to give you a yeast infection (and even if you do have diabetes, it is more about the urine and immune system).

• No evidence shows cranberry juice prevents bladder infections.

• Eating 25 g of fiber a day will help keep your gut healthy, and indirectly that will help your vagina.

• Fermented foods might (emphasis on might) be useful if you are taking antibiotics.