Functional mushrooms seem to be everywhere, but are they 'mush' ado about nothing?

Suddenly, it seems mushrooms are everywhere — and not just in places you might expect, like risotto. They're popping up in products like gummies and power bars that capitalize on the claims that functional mushrooms have natural health properties: brain-boosting, stress-reducing, immunity-fueling, mood-enhancing.

Perhaps mushroom lattes recently appeared on the menu at your local coffee shop, leading you to wonder: What are functional mushrooms? And should I drink them?

“It’s yet the next darling, until people spend an extra $3 and get their mushroom coffee only to wake up the next day and discover they’re no healthier, they’re no smarter and they’re no younger,” Dr. Richard Friedman, professor of clinical psychiatry and director of the psychopharmacology clinic at Weill Cornell Medical College, tells TODAY.com.

When it comes to functional mushrooms, "there’s a lot of speculation and assertion but not a lot of science,” he adds.

What are functional mushrooms?

The health benefits of mushrooms — the kind that you buy in the grocery store and cook with — are well documented. They contain protein, fiber and vitamins that can prevent cell damage, support your nervous and immune systems, boost energy and help maintain a normal blood pressure, according to the Cleveland Clinic.

Some mushrooms also contain “plant substances” that don’t provide nutritional value but have been found in cell and animal studies to possibly have “antioxidant, anti-inflammatory, and anticancer effects,” according to Harvard’s T.H. Chan School of Public Health — though “the exact mechanism is still unclear and an area of active research.”

The term "functional mushrooms" refers to the mushrooms that functional medicine advocates believe have properties beyond their nutritional makeup that can be beneficial to your health. While chaga, cordyceps, lion’s mane and reishi aren't the most delicious mushrooms for tossing into a stir fry, you may see them packaged as a powder or another form claiming to bring their purported superpowers into your daily routine.

Will Cole, who holds a doctorate of natural medicine and a chiropractic doctorate and specializes in functional medicine, tells TODAY.com that he believes different functional mushrooms can provide “a wide array of health benefits depending on what you are looking to achieve. For example, lion’s mane is great for boosting cognitive function, while chaga can help support immune function.”

Cole is the wellness director for Kroma Wellness, a company selling “functional foods and beverages” (many of which are mushroom-packed) that it claims will “nourish, heal and transform the entire body.” Cole is working on a new book, “Gut Feelings,” about the connection between our health, what we eat and how we feel.

Friedman tells TODAY.com that he has concerns about any specific health claims regarding functional mushrooms.

Similarly, TODAY contributor Maria Shriver, a longtime advocate for Alzheimer’s research, tells TODAY.com, that when it comes to functional mushrooms and the brain, "You have to be really careful with what you say. ... You can’t say, ‘This prevents Alzheimer’s.’"

Still, Shriver adds, "I think mushrooms are having a moment."

Indeed, there is no shortage of options for the newly mushroom-crazed. Rachel Bukowski, Whole Foods’ senior team leader of product development, tells TODAY.com that she’s noticed the trend building slowly but surely in the last few years, with more functional mushroom products on menus and in stores.

“These mushrooms are making their move from the supplement aisles to new and exciting food and beverage formats, and we expect to watch this trend grow even further in the coming years,” she says.

Benefits of functional mushrooms: What the research shows

“The medicinal or functional benefits of mushrooms, promoted for thousands of years in the East, are steadily gaining recognition in the United States and other parts of the world,” Akua Woolbright, who holds a Ph.D. in nutritional science and is the national nutrition program director for Whole Foods Market’s Whole Cities Foundation, tells TODAY.com.

Unlike many viral food fads that do nothing for health, Woolbright says this is one she can get behind. “While I don’t promote foods made with functional mushrooms as cure-alls, less-processed or refined products can be a part of a healthy lifestyle. The dietary choices that we make on a daily basis have a compounded effect. The positive changes we make, big or small, add up over time.”

Woolbright points to a randomized, double-blinded, controlled study published in the journal Frontiers in Aging Neuroscience in June 2020. Participants with mild Alzheimer's disease showed a significant benefit in reducing cognitive decline after orally taking three capsules containing lion's mane every day for 49 weeks when compared to the placebo group.

Another literature review looking at the medicinal properties of mushrooms (one aspect that makes them "functional") published in the International Journal of Molecular Sciences noted: “Many clinical investigations have shown very encouraging or promising results, thus underlining the great potential of mushrooms in therapeutic applications."

However, the same review cautioned that a single species of functional mushroom can be sold in varying doses and preparations with different manufacturing practices and have different claims associated with it. (The U.S. Food and Drug Administration doesn't approve claims or labels on dietary supplements before they're marketed and takes action on misbranded products only after they reach the market.)

"In the absence of standardization, significant differences can be found even in different batches from the same manufacturer," the authors of the review wrote.

Friedman also cautions that studies that have found that higher mushroom intake can have protective effects on brain cognition in older adults don’t necessarily prove that mushrooms are the cause of better cognition, he says.

“Maybe people who had better cognition like mushrooms and eat more of them, or is it that mushroom-eating enhances cognition?” he explains. “That’s the problem with observational studies, and all of nutrition has that problem. And even if you try to control for all those factors, they’re mostly short-term studies that are a snapshot in time. So it’s impossible to know."

What to know if you're considering trying functional mushrooms

Having realistic expectations for what functional mushrooms can and can’t do may be the key to deciding whether these products are for you. Even functional mushroom advocates agree that you should not expect to be flooded with immediate, noticeable benefits from just one snack.

Cole says that the average daily dose — between 1,000 to 2,000 mg — is a common serving size you’ll see in most functional mushroom products. But he believes taking them consistently is the most important part. (In the previously mentioned study that found improved cognition in Alzheimer's patients, they took lion's mane capsules every day.)

Cole recommends choosing a particular problem you want to address and targeting it with a specific functional mushroom that aligns with your goals. You should not, however, take functional mushrooms instead of seeking help from your health care provider. As Cole's website notes, his advice is "not meant to substitute or replace those of a medical doctor" but rather "work in conjunction with them."

Talk to your doctor before adding any new supplements, mushrooms or otherwise, into your diet.

A final word on functional mushrooms

In the first months of the new year, when health is top of mind for millions of Americans, even a skeptic like Friedman doesn’t want to stop anyone from enjoying functional mushrooms, and he says there's no harm in trying them out.

“Mushrooms are delicious. By all means, eat them. But if you want to claim they’re going to lower your risk of dementia or make you smarter or live longer … boy, you have a big scientific problem," he stresses. "That shouldn’t stop you from enjoying them. What it should do is stop you from making health claims.”

Friedman’s best advice is decidedly old-fashioned: “If you want health, you should spend that money on a gym membership."

This article was originally published on TODAY.com