The 2017 glitter trend is going strong. It reached the point where people started swallowing glitter pills to make their poo sparkly. Now glitter gel capsules intended to be inserted into the vagina, known as Passion Dust, are selling out. Needless to say, gynaecologists have slated them as untested and very probably unsafe.

A healthy vagina is a delicate ecosystem. It has a precise balance of moisture, pH and bacteria. People can safely put all kinds of things in vaginas – tampons, penises, sex toys, to name a few. But inserting a glitter bomb is one of the worst things you could do to disrupt vaginal harmony.

Edible glitter is full of tiny bits of starch – like what you might dust a cake with – suspended in a gel of some unknown substance. Although this might be fine to put in your mouth, the vagina is another matter.

"Being able to eat something does not mean it is safe for vaginal application. I can eat a burger or a cinnamon bun and suffer no oral issues, but I would hate to see what they would do to my vagina," Canadian gynaecologist and blogger Jen Gunter told IBTimes UK.

"If the glitter is made of starch then it is essentially made of sugar. The enzyme amylase breaks starch down to glucose and vaginal fluid contains alpha-amylase. We don't know what introducing pharmacological amounts of glucose could do to the vaginal ecosystem," Gunter said.

The effects of sugary vagina glitter capsules, which Gunter likens to unicorn ejaculate, is anyone's guess as the Passion Dust website doesn't detail which safety tests, if any, the product has been through. Passion Dust did not respond to a request for information on their safety precautions by the time this article was published.

Putting sugary substances into the vagina is rarely a good idea, Gunter said. The bacteria that cause infections in the vagina thrive on it.

"Early studies looking at using vaginal probiotics for bacterial vaginosis had issues because the glucose/nutrient in the probiotic capsule needed to keep the probiotic alive acted as a growth accelerant for bad bacteria. So the bad bacteria over grew before the good bacteria could grow."

Glitter is fun, in the right places. Your vagina is not one of them. Kate Ter Haar

Another potential problem with Passion Dust is whether it has the potential to draw water out of the vaginal tissues. In the same way very salty food can draw water from your tissues and cause dehydration, very sugary substances inserted into the vagina could cause dehydration and trauma to tissues, Gunter said.

More broadly, the lack of information about how the product is made, as well as tested for safety, is a real concern.

"You really have no idea what is in the capsules. This isn't a pharmaceutical so who knows if [the manufacturer] is mixing this up in her kitchen counter right after she made chicken or if it is made in an appropriate lab environment," Gunter said.