Raise your hand if you’re taking a vitamin every single day (or, at least, you try to). You’re not alone—over 70 percent of adults in the U.S. take some kind of supplement. But while most of us are well-familiar with the capsules and gummies on the shelves at Whole Foods (and perhaps are willing to try the IV drips and shots popping up in spas and wellness boutiques), how would you feel about inhaling your vitamins instead of swallowing a pill?

Enter vitamin vapes. The makers of these products, which have exploded onto the market recently, say they’re nixing all the “bad” chemicals like nicotine that traditionally go in vapes, and instead are filling the pens with vitamin compounds. Some examples: NutroVape (a line of 11 different blends meant to work in place of an oral supplement), Breathe (a vitamin B12 vape pen), and Nutriair (which formulates blends to promote benefits including more energy to better sleep).

It certainly sounds promising, especially given how mainstream vaping has become. But are vitamin vapes truly the supplement of the future?

George Michalopoulos, founder of Breathe, certainly thinks so. He came up with the idea of a vitamin B12 vape about five years ago, around the same time that vaping was starting to become popular. “I was trying to be vegan—although I no longer am—and when you’re vegan, you’re at greater risk for being deficient in vitamin B12,” he says. He started doing some research and found a study about inhaling vitamin B12. “The research said [B12 was better absorbed when inhaled] than taking it as a pill, but not as effective as the shot,” he says. (It should be noted that this study he references is from the ’50s and was performed on only three different people, so it is far from conclusive. And another small study from 1967 found that inhaling B12 “is considered to have no therapeutic application.”)

While Michalopoulos is touting Breathe as a way to get vitamin B12, he acknowledges the limitations of existing evidence, and he’s hesitant to label his company’s product as healthy. “I don’t like saying ‘healthy vapes,'” he says. “It’s a very heavy term. But I will say that calling something healthy is a very difficult threshold to meet, because the 20- or 30-year studies just aren’t there yet.”

Avi Kwitel, co-founder of the vitamin vape brand Sparq Vitamin Air, on the other hand, is comfortable calling his company’s product something that “promotes wellness.” He says that his brand,  which sells three vitamin blends—one meant to boost metabolism, one for energy, and one for anti-aging—is rooted in wellness. “[My business partner] Mark Greenspan and I were working out a the gym and he said, ‘How cool would it be if we could change people’s perception around inhalation and associate it with wellness as opposed to cigarettes and nicotine and unhealth?'”

Getting the healthy stamp of approval by MDs, however, isn’t quite there. Michael Blaha, MD, MPH, associate professor of cardiology and epidemiology and director of clinical research for the Johns Hopkins Ciccarone Center for the Prevention of Heart Disease, is not on board with the whole concept of vitamin vapes—at all. “From the purely scientific and medical point of view, I can definitely say that there’s no evidence [in favor of] vaping anything,” he says. “The lungs are supposed to breathe in air. We’re not meant to absorb anything through the lungs. We were not evolutionarily designed to absorb any nutrition or minerals or vitamins that way.”

It should be noted that Dr. Blaha is skeptical of supplements in general, not just those that come in a vape pen. “There isn’t great evidence that supplementation in any form has long-lasting health benefits,” he says. To his point, a 2018 review in the Journal of the American College of Cardiology found that “conclusive evidence for the benefit of any supplement across all dietary backgrounds (including deficiency and sufficiency) was not demonstrated.” As Dr. Blaha sees it, the jury is still out on oral supplements, and vaping them has even less evidence to support their use.

“From the purely scientific and medical point of view, I can definitely say that there’s no evidence in favor of vaping anything.” —Michael Blaha, MD, MPH

Vitamin vapes also contain other ingredients besides the vitamins, something Dr. Blaha takes issue with. “None of these products are pure whatever the vitamin is,” he says. “They also contain vegetable glycerin and natural flavors—and it’s never listed what those natural flavors are exactly—and then there’s the metal heating coil, which gives you trace metal exposure.” That means you could be putting yourself at risk for issues like an upset stomach as well as more serious conditions like kidney disease and lung damage.

To this, Michalopoulos says the research about trace metal exposure through metal heating coil is inconclusive, and any studies that have been done have used higher-powered vaporizers that undergo a much higher heat than what the ones most vitamin vaping products use.

Over at Sparq, Kwitel says, “We take the science of inhalation very seriously. Two years ago, we hired a renowned inhalation toxicologist to handle the construction of our formulations and subsequent lab testing. Together we ensure that all of the ingredients we use both survive the heating process and do not denature or cause any harmful byproducts.” He hopes to start testing on humans soon, with the goal of Sparq being available to purchase online in January.

The bottom line: Because the entire field is so new, there’s not a ton of evidence that vaping vitamins is inherently good or bad for you. But Dr. Blaha says that’s still not a good reason to do it. “I don’t have any evidence that it’s harmful, but I would say that the burden of proof on a new product would have to be on them, because basically they’re saying it’s beneficial.” You could say that when it comes to vaping your vitamins, we’re sill waiting for the smoke to clear.

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