Rob Nelson didn't set out to become a mushroom evangelist. The wildlife educator and host of Untamed Science was skeptical when he first heard the claims that mushrooms that sharpen your brain, boost athletic performance, help you sleep better, and even fight cancer. It sounded like pseudoscience.
But after months of investigation - talking to experts, visiting mushroom farms, and experimenting on himself - Nelson emerged convinced that we're in the middle of a mushroom revolution that most people are completely missing.
"I was skeptical too," Nelson admits in a video. And his skepticism led him on a journey that took him from his own home experiments to Mushroom Mountain in South Carolina, where he found everything he needed to visually demonstrate what he was learning.
The Exclusive Club
Here's what got Nelson's attention initially: Out of an estimated 3 million mushroom species on Earth, only about 14,000 have been discovered and named by science. And of those, only about a dozen have passed what Nelson calls "the insanely high bar" to be considered functional mushrooms (mushrooms with proven health benefits backed by actual research).
"That's 0.0004% of all mushrooms," Nelson points out. "Either way you slice it, that is an exceedingly exclusive club."
So what makes these particular mushrooms so special? Nelson compiled a top-five list based on his research and personal testing.
Lion's Mane: The Brain Mushroom That Started It All
Lion's mane was Nelson's gateway into medicinal mushrooms. A few years ago, his partner Haley cooked one up for him. "It definitely tastes like a mushroom," he recalls. "It's a wonderful meat substitute and really a delicacy." But it's rare to find in grocery stores because the shelf life isn't great.
What makes lion's mane special isn't just its texture. It's what happens in your brain when you take it regularly. The mushroom contains two compounds found nowhere else in nature: hericenones and erinacines. These promote nerve growth factor (NGF) in the brain, something that when depleted can lead to Alzheimer's and dementia.
"It has been found that taking them helps repair the myelin sheath that is found in the nerves of the brain and spinal cord," Nelson explains. It's also helpful for people recovering from brain and spinal cord injuries.
Explore our lion's mane here.
Turkey Tail: The Cancer Fighter Hiding in Plain Sight
On a trail walk at Mushroom Mountain, Nelson crouches down to examine a common sight in forests: turkey tail mushrooms growing on a log. "This is a wildly common mushroom throughout North America," he notes. "In fact, a lot of mushroom growers see them as weeds."
But this humble mushroom is one of the most well-documented medicinal mushrooms in the world. The majority of studies focus on turkey tail for treating various forms of cancer.
Trad, Nelson's guide at Mushroom Mountain, explains it this way: "This is the number one product taken for cancer treatment in Japan. It's a PSK—a polysaccharide that's derived from turkey tail mushrooms. The great thing about it is that it has little to no side effects, and a lot of the drugs people are taking have a lot of different side effects or adverse reactions."
"Turkey tail is a great, wonderful little mushroom," Nelson reflects. "I used to just pass by them for years, and now it's like every fungus is significant."
Explore our Turkey Tail here.
Cordyceps: From Zombie Ant Fungus to Athletic Enhancer
Nelson's most unsettling discovery came while examining a dead ant on the trail. Trad points out that it's been infected with cordyceps, a fungus that drills into an insect's armour, threads into its muscles and nerves, and takes remote control of its brain.
"It never goes home again," Trad explains. "It secretes a toxin, and then the mushroom kills the ant, and a little structure called a cordyceps pops out the back of his brain."
The story gets crazier when you learn that Cordyceps sinensis (which grows from caterpillar heads in the Himalayas) is the most expensive fungi in the world. To understand the global fascination with this mushroom, Nelson reached out to Hamilton Morris, a filmmaker and ethnomycologist who's documented cordyceps harvesting in Nepal, China, and Tibet.
"The lived experience cannot be denied," Hamilton told Nelson. "The amount of people that I know personally and people that I have met through the community—their experiences cannot be denied. They have healed themselves from chronic pain and illness using medicinal mushrooms."
But wild Cordyceps sinensis would be far too expensive for most people. Luckily, places like Mushroom Mountain have figured out how to cultivate a related species, Cordyceps militaris, without insects. This means the benefits (including immune health, cardiovascular fitness, and exercise performance) are now affordable.
Nelson has been taking cordyceps for his workouts. His friend Stefan has too. "Cordyceps took me maybe two, three weeks to really start noticing," Stefan reports. "That's what the best research shows—at the three-week mark is when your performance metrics, VO2 max, some of these other things go up."
Explore our Cordyceps here.
Chaga: The Ugly Duckling Antioxidant
Chaga looks like a blackened lump on birch trees, so not particularly appealing. But the relationship between the fungus and the tree is crucial. One of chaga's key compounds, betulin, actually comes from the birch itself.
"If you just grew chaga by itself or grew the mycelium out on grain or something like that, it wouldn't contain that betulin," Rob explains. "So wild-harvested chaga that grows on birch is actually important for the beneficial compounds."
"The other interesting thing about chaga is it's a super powerful antioxidant," Rob continues. "It is one of the highest concentration antioxidants of any of the natural products you will ever see."
Explore our Chaga here.
Reishi: The King of Mushrooms
A "It's such a cool mushroom, and it's surprisingly hard," Nelson says. The shiny, varnished appearance gives it the nickname "varnished conch."
Reishi is known as the "king of mushrooms" and has been used in Asian medicine for thousands of years. It's bitter and woody, so not meant for eating, but that bitterness comes from powerful compounds called ganoderic acids that help with sleep and relaxation.
"I took reishi last night," Nelson reports after his first experiment. "Wow, I slept like a log."
He even learned that Dr. Conover, whom he'd interviewed for a previous video on ketamine, uses reishi in his sleep formula along with CBD, magnesium, L-theanine, and other compounds to help patients relax.
Explore our reishi here.
The Common Thread: Beta-Glucans
After weeks of research, Nelson discovered what ties all these mushrooms together: beta-glucans. These polysaccharides are found in the cell walls of mushrooms, and they're incredibly tough compounds.
"Mushrooms are composed of chitin," Trad explains. "It's like you're eating a chemical component identical to what's in a crab shell. If you eat a raw mushroom, it's passing through you. If you cook a mushroom, you're actually getting access—your body can access the protein and the medicinal properties."
The beta-glucans are what give mushrooms their immunoregulatory properties. "What that means is it helps increase your immune cells to fight an infection," Nelson explains, "and at the same time, it can regulate back if you start to have an adverse immune overreaction. It's crazy, isn't it? It means you can regulate up or down at the same time."
The Skeptic's Conclusion
Nelson wraps up his investigation with a recommendation and a caveat. "I want to recommend that all of you out there look into medicinal mushrooms," he says. "It is a fascinating field."
He points viewers to three key books: Christopher Hobbs' "Medicinal Mushrooms" for beginners, and Robert Rogers' "The Fungal Pharmacy" and "The Human Clinical Trials" for those who want to dive deep into the actual studies.
"In a video like this, I can't go through all of the studies, and if you're skeptical right now, you probably should be—that's important," Nelson acknowledges. "But if you do take something with you, I hope it's just a general understanding that there are compounds out there that maybe aren't as popular in our culture as they could be, and if you mix them into your diet, it might actually benefit you in certain ways."
After four months of growing mushrooms in bags, hiking through forests, and experimenting on himself, Rob Nelson has gone from skeptic to advocate. Not because of marketing hype, but because the science, and his own experience, convinced him that the mushroom revolution is real.
Explore our full range of functional mushroom supplements here.
Watch Rob's video here
