Functional Mushrooms and The Barriers For Clinical Research

From chocolate bars, to gummies, sparkling beverages, and supplements, functional mushrooms are showing up everywhere. Mushrooms like Lion’s Mane and Cordyceps have practically become household names, mainstream concepts that don’t need additional context in everyday conversations. Ten years ago, they were practically unheard of outside of niche circles, while today, they’re ingrained in the cultural zeitgeist.

But despite their growing popularity, many skeptics claim scientific research has not kept pace with the hype. While functional mushrooms are backed by centuries of traditional use and a growing body of studies, critics suggest that large-scale clinical trials, considered the “gold standard” of modern medicine, are severely lacking.

While this may be true when comparing them to modern pharmaceuticals, natural therapeutics like mushrooms encounter unique challenges in the landscape of clinical research. This includes limitations in funding and difficulties with standardization. This article explores the barriers that have prevented functional mushrooms from receiving the same level of clinical validation as pharmaceutical drugs and why the expectations of some critics are not realistic when it comes to natural products.

Between The Science and The Hype

The market analyst Grand View Research estimated the global functional mushroom industry was valued at 34.75 billion USD in 2024, a significant leap from about 20 billion USD in 2018. That’s almost 75% growth in six years. It’s estimated that by 2030 it could be valued at 65.83 billion. In North America, the functional mushroom industry was valued at about 612 million in 2024, and is expected to reach 1.41 billion by 2030. This rapid expansion reflects a growing interest in the world of functional mushrooms.

Yet, with so much rise in popularity, there is no doubt room for skepticism.

After all, you may have seen foolhardy mushroom coffee ads, sometimes delivered by internet influencers, that make larger than life claims about their products. They’re black-hat marketing tactics utilize a panacea-filled narrative that reads like mushroom snake oil. This fact becomes more evident once you realize most products on the market have serious quality concerns.

Critics though, should not mistake the hype for complete falsehood. Mushrooms, in all their diverse forms, offer many health benefits and potential therapies. After all, it is estimated there are between 53,000 and 110,000 macrofungi (fungi we can see with the naked eye) on the planet, many with compounds of medical interest. They aren’t a panacea as portrayed in some marketing campaigns, but when taken adequately or consumed regularly in meals, they could benefit human health or offer potential therapies.

People have known this for centuries. In Europe, people have historically used Chaga, Agarikon, Amadeu, and other mushrooms in traditional practices. Dioscorides, the Greek physician, wrote about using Agarikon almost 2,000 years ago for tuberculosis, dysentery, and other ailments. In India, a country not considered particularly mycophillic (mushroom loving), there are at least 100 different species of fungi used medicinally. Mexican mycologist Gaston Guzman listed at least 70 utilized in Mexico, although this number is likely much greater.

Nowhere else is the traditional use of mushrooms more evident than in China. There, mushrooms have formed a part of the pharmacopeia for thousands of years and remain a very valid component of Traditional Chinese Medicine. In China, functional mushrooms have been mainstream long before the “shroom boom” of the west, of which they were vastly influential.

But as critics will point out, traditional medicines don’t always live up to the expectations of modern medicine. Their effects may not align with conventional practices, or they might pose greater side effects compared to existing drugs. Admittedly, some of them might not be effective, especially outside their traditional context.

Clinical Trials As The Gold Standard Of Modern Medicine

It is for the reasons mentioned above that medical researchers have developed strict protocols to determine the efficacy of a new drug or medicine. These typically follow a standard pipeline that starts with analyzing the biochemistry of the drug, then testing them on cell cultures, followed by animals, and eventually humans.

Human trials are considered the gold standard and have 3 main phases in which they take place. Phase 1 tests the safety and dosages, phase 2 the effectiveness and side effects, and phase 3 compares them to the conventional treatments. Once a drug undergoes all three phases with promising results, it can be submitted for regulatory approval.

Last year, I released a database of clinical trials conducted on medicinal mushrooms, which you can explore at mushroomclinicaltrials.com. It features nearly 200 studies on various mushrooms and their active compounds, along with a handy search function to make research easier. For full transparency, there is an affiliate marketing component to the website, and I do promote certain brands that have shown utmost commitment to providing high-quality products.

Yet, even as the author of this website and someone with a vested interest in the industry, it is evident that there is room for further research to fully understand the efficacy, dosages, and benefits that are offered by different mushrooms. Compared to pharmaceutical drugs, which often undergo trials with tens of thousands of participants, functional mushrooms have trials that, on the high end, usually include just a couple hundred participants.

Barriers To Clinical Research

The lack of clinical research is not something unique to mushrooms. Almost all natural therapeutics struggle to undergo extensive clinical trials, not because they can’t offer novel treatments, but in many cases, it’s because of inherent challenges that come along with natural products in the context of clinical research.

To begin, natural products can contain hundreds of different compounds. These can be synergetic, antagonistic, or react together in many different ways. This can make it difficult for researchers to pin-down the actual mechanisms in which they function and how their effects can be improved or modified. It also makes it difficult to predict potential side-effects or negative interactions with other medicines.

Similarly, the nature of primary materials can also pose challenges to researchers. The chemical profile of a material can vary greatly depending on the strain, growing conditions, drying, storage, and many other factors. Just because researchers use the same species does not mean the results will be replicated in a different study. For this reason, many of the trials featured on my website are not on mushrooms themselves but highly refined extracts rich in a specific compound. This makes it much easier to study in the clinical context. Finally, we come to one of the biggest hurdles in conducting clinical research on functional mushrooms and botanicals. The funding. Extensive clinical trials can cost tens of millions of dollars, and can easily add up to hundreds of millions when multiple phases are conducted. And, unlike laboratory-derived pharmaceuticals, natural products cannot be patented. This significantly reduces the incentive for companies to pursue research on a product they can not have proprietary rights to. It is these proprietary rights which actually finances most clinical research. Under US Law (35 U.S.C. § 101) , “products of nature” cannot be patented unless they are significantly modified or applied in a novel way. Similar laws exist around the world.

Don’t get me wrong though, this law is a good thing. A very good thing in fact. It is the legal framework that grants natural products protection from the grasp of corporate control and ownership. They prevent companies from establishing a monopoly on things that naturally occur and often have a legacy of traditional use.

This type of protection also stops biopiracy, such as the case when US researchers placed a patent on turmeric in the early 90s. The patent, which claimed turmeric’s wound-healing properties as a novel invention, was challenged by the Indian government who successfully proved that these medicinal uses existed for centuries. The patent was ultimately revoked, setting a precedent for protecting traditional knowledge from corporate exploitation.

Pharmaceutical Grade “Mushroom” Extracts

While mushrooms, plants, or the compounds they produce cannot be patented, investors can secure their stake in research through patents or proprietary knowledge on the methods/technology utilized in making highly refined extracts.

Afterall, we aren’t talking about the questionable double-extraction tincture some traveler-dude gave you in a parking-lot. The materials utilized in clinical research are highly refined pharmaceutical-grade extracts produced in state of the art facilities. Most of these aren’t even made from fruiting bodies like you might expect, but instead from mycelium from specialized strains cultivated in liquid medium within bioreactors. This is known as submerged-fermentation in the literature.

Take, for example, PSK, an extensively studied protein-bound polysaccharide derived from Turkey Tail mycelia. It’s been used in dozens of clinical studies with tens of thousands of participants, primarily as a support for conventional cancer treatments like chemotherapy. A 2007 meta-analysis included data from trials that collectively had over 8,000 gastric cancer patients who utilized PSK in part of their treatments. Some significant multi-year trials also support the addition of PSK in the treatment of breast cancer.

Another extensively researched compound is known as Lentinan and derived from Shiitake. Like PSK, it has been studied as a support for conventional cancer treatments. It is found in the mushroom fruiting bodies, but is also produced by submerged fermentation. Its potential role in cancer treatments has been evaluated in thousands of patients, as indicated in this meta-analysis of over 3,000 lung cancer patients. Studies have also investigated Lentinan as an adjunct treatment for gastric and ovarian cancers. Note that the study cited investigating the use of lentinan in gastric cancer did not show any efficacy.

Bridging Traditional and Modern Medicine

The reality is that while functional mushrooms have gained mainstream attention, their place in modern medicine is still being defined. The demand for large-scale clinical trials is understandable, but the current research landscape makes such studies unlikely to occur in the near future.

For now, functional mushrooms sit at the intersection of tradition and science, supported by centuries of cultural use and growing modern research. While they are not the miracle cure that some marketing might suggest, they are also far more than a passing wellness trend. With continued study, better standardization, and an open-minded yet critical approach, we can continue uncovering the real therapeutic value these fungi have to offer.

Contributing Author: Timo Mendez

Timo Mendez is a mushroom specialist, freelance writer, and founder of mushroomclinicaltrials.com.

You can find out more at his website, encounteringfungi.com.