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The over-the-top garnish is topping more and more dishes. But does it digest?

Instagram has recently turned gold sushi and doughnuts into extravagant, viral sensations, but humankind had long had an appetite for the glittery, malleable metal. While you’re being dazzled by sparkling gold flakes suspended in your cocktail, or the delicately laid leaf surrounding your bonbon, one thought may cross your mind: “can I really eat gold?” Or, if you’re like me, the question is just “why eat gold?” Afterall, it's basically flavorless.

Regardless, for centuries, thinly pounded sheets of pure gold have been used as garnish in European pastries and ground into Japanese green tea. As far as we know, nobody has died from gold poisoning (except the lady in that James Bond movie and that Targaryen dude in Game of Thrones… oh, spoiler alerts). I asked a couple of nutrition experts, New York-based registered dietitians Alexandra Oppenheimer and Cynthia Sass, to weigh in on the prospect of gold being harmful to your biology.

Oppenheimer points out that when you do eat gold, you’re not just eating your wedding ring. “Edible gold must be 23-24 carats,” she tells me. “It’s not the same gold you find in your jewelry, which may have other metals and can be toxic and dangerous if consumed.” The gold used for edible applications is known, at least in Europe, as E-175, a designation given by the European Food Safety Administration (EFSA) when using the metal as an additive or food coloring. The effects and safety of E-175 were first evaluated back in 1975 and recently re-evaluated in 2016 by EFSA.

According to that most recent opinion, gold leaf must be 90 percent pure gold, with the other 10 percent typically consisting of another safe metal, like pure silver. Assuming your gold checks out (and, to be fair, from all available information the gold leaf currently sold as “edible” does pass the test) it’s not going to do anything to you. Scientifically speaking, gold is chemically inert, meaning it won’t break down during digestion.  “Most likely edible gold won’t be absorbed from the digestive system into the bloodstream, and therefore it will pass through the body and eliminated as waste,” Sass explains. “But this may depend on the size, amount, and frequency consumed.”

And that’s where the research on gold as a food additive hits a slight roadblock — that roadblock being the near non-existence of any research.

The EFSA cites a “lack of data on toxicity, purity and the exact nature of gold used on or in foods.” So, to fill in the gaps they, appropriately, looked at gold dental fillings for insight. As gold has been commonly used for decades in dentistry, we do know that the effects of it on the body are, at the worst, a rash for those hypersensitive to the metal. Gold particles do appear in the saliva samples of people with gold fillings, so it’d be safe to assume those people are swallowing them and that it is not causing any harm.

Another application of ingested gold is in medications, which have been used homeopathically throughout history, but also pharmaceutically, as it is in the treatment of rheumatism. In the latter case, gold is used in conjunction with sulphur and phosphor as a sort of a delivery system for the actual medication and some studies suggest the precious metal has anti-inflammatory capabilities. The only danger gold could produce is on the nanoparticle level where it can be destructive to cells when injected directly into them in lab experiments. However since gold nanoparticles are too big to permeate a cell membrane, that threat is nearly non-existent. The EFSA findings do indicate that liquors like Goldschlager could have suspended gold nanoparticles in them, but again, they don’t seem to be able to do much to you.

Video: Vanilla Bean Kulfi at Paowalla

At this point, you may have noticed everything referenced above about the safety of gold as a food additive is from a European inquiry. In fact, the U.S. Food & Drug Administration (FDA) doesn’t have guidelines for gold consumption, specifically due to a lack of inquiries about it (though they do tell you to make sure you’re not eating inedible metals on your cupcakes). The closest the United States can come to an official stance is from the Centers for Disease Control, which does not designate gold as a poison. So there you go: gold is not poison.

Still, it’s probably best to not make gold part of your daily diet. “I recommend exercising caution when selecting your dining bling,” Oppenheimer warns. “Since it’s not well studied, let it only adorn on seldom special occasions.” Sass agrees, saying a gold adorned meal should be a “once in a lifetime” event.

In short, we really don’t know too much about what happens when we eat gold, other than it makes our poop extra fancy. And even then, Oppenheimer says don’t get your hopes up. “It’s highly unlikely that you’ll see it come out the other end as it will likely be hidden in the rest of your fine dining experience.” The good news? It probably won’t harm you. The bad news? Until more studies are conducted, we’ll have to keep saying “probably.”