We all want to sleep better, feel less stressed out, have more energy and fewer illnesses, and we'd like to be able to think more clearly, too. If only there were a magical potion we could drink to obtain all of these qualities.

Makers of what have been deemed "functional mushrooms" think they have that elixir. As a result, mushrooms are turning up in coffee, chocolate, even beauty "dusts."

Mushrooms fit into the emerging category of "adaptogenic foods"— ones with natural compounds that promote or restore normal physiological functioning. They've long been part of holistic medicine, but trend watchers are predicting that 2018 is the year they'll go mainstream.

These days, you can go to a wellness cafe in Los Angeles and order a "'shroom shake" or a lemon juice tea with mushrooms in it. Mushroom teas have a high-profile booster in Gwyneth Paltrow, the famous peddler of domestic potions for the elite on her lifestyle website, Goop. One company promoted on her site, Moon Juice, sells a variety of powdered mushrooms that the company claims enhance various aspects of a person: their beauty, brains, sex life, mood and energy.

Four Sigmatic is another brand leading the charge. The company's founder, Tero Isokauppila — a 13th-generation mushroom forager — wrote a book called "Healing Mushrooms" that outlines the properties behind each.

There's reishi, a mushroom he says will keep your skin healthy, give you a better night's rest, reduce stress and cure seasonal allergies. There's chaga, which he says is rich in antioxidants, can fight off the common cold, lower inflammation and make your hair shiny. There's cordyceps, which he says increases energy and enhances performance "both athletically and in the bedroom." And there's lion's mane, which he claims can reverse dementia and boost concentration and memory.

On the other hand

If it all sounds too good to be true, well, there are some doctors and nutritionists who agree with that assessment.

"Like most trends, there's a lot of big claims being made," said Mascha Davis, a registered dietitian/nutritionist and spokeswoman for the Academy of Nutrition and Dietetics. "There is some research showing some beneficial utilities in some mushrooms, but I think some of these companies that want to sell them overstate the benefits."

For example: Reishi mushrooms have been found to have "antioxidant, antitumor, immune-modulating, cardiovascular, antiviral and antibacterial effects," according to studies cited in Today's Dietitian. But Davis cautioned that there has not been enough research yet, and that some of the studies people use to back up mushroom-related claims were performed only with rodents, not people.

Some of the other positive attributes cited in some studies — such as certain mushrooms' ability to thin blood — can be harmful if the mushroom is combined with some medications, she said.

And then there's the taste test. We thought Four Sigmatic's coffee and hot cocoa would have that earthy, mushroomy flavor, and were pleasantly surprised that they didn't. We wouldn't go so far to say that they taste as good as the non-mushroom kind, though.

The hot cocoa, which promises "chill-out vibes with reishi," was tongue-coatingly viscous, and if you are sensitive to the taste of non-sugar sweeteners, you'll taste the Stevia overwhelmingly (and a nice hint of cinnamon, too). The coffee, which we tried black, was bitter and not as rich as brewed coffee.

NordicNordic's cinnamon chaga tea was very light, with just a hint of earthiness from the mushroom and a stronger cinnamon smell than flavor.

Hold the beef

Some mushroom products aren't making any health claims but are aiming the fungi squarely at customers who want a meat substitute. Panco Foods' Pan's Mushroom Jerky, for instance, is nicely chewy, dry (in a good way) and slightly sweet, but perhaps not salty enough. The mushroom flavor is prominent, and it works.

If you want to get really serious about medicinal mushrooms, Davis recommends consulting a doctor — not Goop.

"The first thing I would tell people if they're really curious about mushrooms is that they should try culinary mushrooms, like portobellos and shiitake" — good sources of antioxidants — "which you can incorporate into your diet without having to get these really expensive powders," Davis said.

She's not totally down on mushrooms.

"I think it would be prudent to be cautious," she said. But at the same time, "I think it's a really exciting area. There are signs that point to some really interesting benefits."