I first heard about Reishi Mushroom powder some time ago via the Tim Ferriss podcast, I looked into it at the time and considered writing a post about it, but then got sidetracked on other projects.

I’d totally forgotten about it until yesterday, when a friend of mine invited me to join her in a new “business venture“, which she thought would be right up my street, as she knows I’m into both entrepreneurship and health and nutrition.

It turns out that said business venture was in fact selling Reishi Mushroom Powder products – Teas, Coffees and Shakes – which she explained she’d been introduced to by her parents after they’d both experienced miraculous health benefits after just a few weeks of consuming them.

Persuaded by her parents’ testimonials, she tried the powders herself, and a nagging shoulder pain from an old injury cleared up within a couple of weeks, and she herself was converted to this wonderful panacea…

Reishi or Lingzhi Mushroom
Eric Steinert, CC-BY-SA-3.0 via Wikimedia Commons

The Sceptics Dilema

Spoiler alert – I’m not convinced by Reishi Mushroom Powder.

I have no interest in taking it for myself, and certainly do not want to be involved in its promotion or sale to anyone else (for reasons I shall explain below).

My dilema was how to break this to my friend, who was clearly invested in the powders both emotionally and financially – convinced that they have cured her mother’s mystery illness, made her father more smiley and jolly, helped a relative’s arthritis, reduced her nagging shoulder pain, and brought her potential financial security (she’s a very talented contemporary dancer, but work can be very sporadic).

I recently came across the netflix show “Adam Ruins Everything” where the presenter busts popular myths and thus ruins people’s days – did I really want to ruin my friend’s hopes and aspirations for 2019?

The easy way out would be to simply say, “I’m sorry I’m not in a position to invest time or money in any other projects now, best of luck with it though”.

While that is true, it’s not the whole truth, as even if I did have unlimited time and money, I still wouldn’t have been interested in investing.

I’m comitted to 100% truth, so had to bite the bullet and explain to her exactly why I wasn’t interested at this time.

I don’t think I ruined her day. In fact, I don’t think there is anything I could realistically say or do to shake her belief in the power of Reishi.

I did think, however, that some of you out there might find my thoughts on Reishi Powder useful, and furthermore, I think the arguments are applicable to the much broader field of Herbal Medicines and Nutritional Supplements in general, so thought it was about time I finally wrote the article.

Dear Horn Reishi
Hokkaido Reishi Co., Ltd CC BY-SA 3.0, from Wikimedia Commons

What’s the Fuss about Reishi Mushroom Powder?

Reishi is the Japanese name for the mushroom Ganoderma Lucidum (Lingzhi in Chinese Medicine).

These mushrooms, along with maitake and shiitake mushrooms, have been “recognised as medicinal for over 2000 years” and are said to treat a wide range (to say the least) of conditions:

Ganoderma lucidum (Lingzhi or Reishi) is known as a bitter mushroom with remarkable health benefits. The active constituents found in mushrooms include polysaccharides, dietary fibers, oligosaccharides, triterpenoids, peptides and proteins, alcohols and phenols, mineral elements (such as zinc, copper, iodine, selenium, and iron), vitamins, and amino acids. The bioactive components found in the G. lucidum mushroom have numerous health properties to treat diseased conditions such as hepatopathy, chronic hepatitis, nephritis, hypertension, hyperlipemia, arthritis, neurasthenia, insomnia, bronchitis, asthma, gastric ulcers, atherosclerosis, leukopenia, diabetes, anorexia, and cancer. In spite of the voluminous literature available, G. lucidum is used mostly as an immune enhancer and a health supplement, not therapeutically. This review discusses the therapeutic potential of G. luidum to attract the scientific community to consider its therapeutic application where it can be worth pursuing.


A veritable panacea no less! I must be crazy to turn down such an opportunity…

Had to be done, sorry.

Cynicism vs Scepticism

I have many friends who are fans of “alternative therapies and medicine” – homeopathy, acupuncture, chiropracty, herbalism, and beyond.

I’m often accused by them of being a cynic. I simply don’t believe in anything.

This is far from the case, however, and I actually think that Reishi Mushroom Powder is a great example for demonstrating the difference between scepticism and cynicism.

It’s also a great example of the confusions encountered in the world of SCAMs (Supplements and Complementary and Alternative Medicine) between “natural remedies” vs “medicines” vs “supplements” and “whole foods” vs “processed foods”.

I Want to Believe

I am, for the most part, a believer in the pursuit of progress, with the caveat that we should do it responsibly and ethically, ideally without destroying the world (pdf).

I firmly believe that at some point we will design a shake/shakes that provide all necessary nutrition.

I also firmly believe that mushrooms (and many other plants) can and do contain powerful chemical compounds that can have a serious effect on your body chemistry (think psilocybin or alpha-amanitin).

I do not think it is beyond the realms of possibility that there could be some potential health benefits to drinking reishi mushroom tea.

Unfortunately, I also don’t think it’s beyond the realms of possibility that drinking the tea on a regular basis is at best a total waste of money (this stuff is not cheap), or at worst, that there could be potential adverse health effects.

For this reason, I say that I am not interested at this time. If in the future evidence comes to light that there is some benefit from taking Reishi Mushroom Extra supplements (or any other supplement for that matter), and no unwanted side effects, I would of course change my opinion.

Mushrooms can have powerful effects on your health!

A World of Contradictions and Confusion

As a sceptic, and believer in science and progress, I get a lot of conflicting messages from my alternative friends.

On the one hand, they subscribe to the naturalistic fallacy – whole foods, herbal remedies and traditional medicines are good because they are natural. Conventional medicine and processed foods are bad because they are unnatural.

They say that science doesn’t have all the answers, and that we should listen to ancient wisdom.

At the same time though, they will take highly refined supplements and
homeopathic medicines which are manufactured in factories, and are anything but natural and unprocessed, nor a product of ancient wisdom.

Perhaps somewhat ironically, the current scientific consensus says that we should eat predominantly natural, unprocessed whole foods, and that supplementation with vitamins, minerals, and other extracts etc is at best waste of time, at worst possibly harmful.

There is nothing inherently special about natural whole foods, and there is no reason why someday we shouldn’t be able to manufacture shakes and meal replacements that are superior to “real food” – containing only the good stuff, with none of the bad stuff.

But we’re not there yet. Not by a long way.

The “Evidence” for Reishi Mushroom Powder

So, back to Reishi Mushroom powder specifically.

That was a big list of purported benefits that I referenced earlier. Why is it that Reishi Mushroom powder is still lurking in the world of SCAM? Why is it that “In spite of the voluminous literature available, G. lucidum is used mostly as an immune enhancer and a health supplement, not therapeutically”?

Well, it could of course be that the ruling class of evil capitalist Space Lizards is suppressing all the voluminous literature in order to keep the proletariat too riddled with arthritis and cancer to mount an uprising.

I however think that the Space Lizards are too busy plotting against the Bilderberg group to worry about mushrooms right now, so it must be something else.

Could it be that the voluminous literature, perhaps simply isn’t quite so voluminous, and furthermore, is rather weak?


Essentially, the evidence we have so far for Reishi Mushroom Extract comes from:

  • Anecdotal Evidence

The vast majority of “evidence” for Reishi Mushroom Extract supplements come from anecdotal evidence – Johnny started taking it and then conditions X, Y and Z cleared up. It must be the mushroom powder!

Take for example my friend – her mother’s illness disappeared, her father’s mood lifted, her auntie’s arthritis improved, and her shoulder pain went away.

What more evidence could you ask for?

The problem is, that we human beings are very powerful pattern recognition machines. Sometimes too powerful, so that we end up seeing patterns and making connections where we shouldn’t.

Correlation does not imply causation


The human body is amazing.

When we feel ill, the symptoms – be it coughing, fever, vomiting, etc – this is actually our own immune system in action, fighting the invading pathogens.

The severity and duration of these symptoms will vary depending upon the person and the infection, and though of course there are extremely dangerous infections that can prove fatal without medical intervention, in the vast majority of cases the immune system does its job, and eventually you will feel better again.

What often happens in these cases however, is that the sufferer (understandably) wants to find a cure, and so tries various remedies. When they recover from the illness, they mistakenly attribute the remedy as the cause, when in fact the credit should have gone to their own immune system. They just happened to take the remedy at the same time, it’s nothing more than coincidence.

Exactly the same mechanism applies to the shoulder pain. The sensation of pain is produced by your own brain, to limit your movement while your body has chance to repair itself.

In the vast majority of cases, when the body has finished repairing itself, the pain will go away.

Once again however, people are often impatient with their body’s self-repair process and try to speed the processes with supplements and medication. Finally, when the pain does go away, they again wrongly attribute their recovery to the pill or powder, instead of marvelling in wonder at their own body.

One must also take into the account that pain is strange, and particularly susceptible to the placebo effect. Occasionally pain can linger, or feel much more severe than the physical tissue damage should normally warrant for a multitude of reasons. In these cases, often a placebo can alleviate or even dispel the sensation of pain altogether.

It’s important to realise however that there is nothing inherently special about the specific remedy. It is better to learn more about the idiosyncrasies of pain, and the powers of placebo effects, in order to harness them without shelling out huge amounts of cash, being reliant on third parties, or risking unforeseen side effects of mysterious medications.

But what about my friend’s fathers dramatic change in mood? How can we explain his new found energy and joy if it wasn’t the mushroom powder?

We humans are incredibly complex creatures, and one can never know for sure what may have brought about such changes in someone, let alone someone you’ve never met.

Could it have been the mushroom powder? Perhaps.

But could it also have been connected to the fact that the mystery illness of his wife had finally gone away, and he was spending time with his beloved daughter while on holiday in beautiful Barcelona?

I cannot of course say definitively in any of these cases that the mushroom powder definitely did not play a role, either big or small.

What I can say, however, that over the decades I’ve seen many similar claims for all manner of powders and potions, and none has ever actually turned out to be a genuine panacea.

For more on why you shouldn’t hold credence in anecdotal evidence, or use yourself as a human guinea pig, I’d recommend my article on “The Pros and Cons of N=1 Experimentation“.

As anecdotal evidence simply doesn’t cut it, we need to look to real scientific studies. What real evidence is there out there?

  • In Vitro Studies on Cancer Cells

Chemicals extracted from reishi mushrooms have been found to kill cancer cells in petri dishes.

This is certainly interesting, and warrants further research. One should however also bear in mind that lots of things have been found to kill cancer cells in petri dishes. Bleach for example does a very effective job. This doesn’t mean you should start putting it in your coffee.

  • Clinical Trials in Humans with Cancer

Large scale double blind randomised clinical trials in humans are the gold standard when it comes to testing the efficacy of a drug or supplement.

Unfortunately, as far as I can see there aren’t any. I find it unlikely that no one has conducted one. Their absence in the literature would indicate that any such studies have failed to show the desired results, and thus have been relegated to the waste paper basket. This is known as “publication bias“. Rather than the Space Lizards suppressing the truth about Reishi mushrooms, it’s more likely that it’s Big Reishi suppressing it’s failures.

The only vaguely relevant human studies I could find were some small, non-placebo controlled, and as far as I can tell non-randomised and non-blinded studies in cancer patients:

A 2009 study in 34 postmenopausal breast cancer patients of grifola frondosa (Maitake, a “same same but different” mushroom extract) found “immunomodulatory effects”.

The study concluded that:

Oral administration of a polysaccharide extract from Maitake mushroom is associated with both immunologically stimulatory and inhibitory measurable effects in peripheral blood. Cancer patients should be made aware of the fact that botanical agents produce more complex effects than assumed, and may depress as well as enhance immune function.


It should also be noted that the sample size was very small (34 people) and the dose-response curve was all over the place (so possibly the variations in immune function were just random).

A 2008 Study of patients with hepatocellular carcinoma reported positive results from combining the administration of lentinan (a fungal extract) with conventional treatments of transcatheter arterial chemoembolisation (TACE) and radiofrequency ablation (RFA).

The tumour necrosis was significantly higher in the combination group (88.6%), compared to the TACE group (37.5%), the RFA group (47.8%) and the TACE/RFA group (60.3%; P<0.05). The tumour recurrence rate was significantly lower in the combination group (17.8%), compared to the TACE group (45.8%), the RFA group (34.7%) and the TACE/RFA group (29.0%; P<0.05). Finally, mean survival duration was significantly higher in the combination group (28.2 months; P<0.05).


Again, these results might sound very impressive, but one must again take into account that the sample size is small, so presenting the results as percentages could be highly misleading.

It could just take one or two individuals in the combination group to make miraculous recoveries, all their tumors to disappear and then go on to live very long lives to totally skew the results.

This is not to say that it’s not possible that the mushroom extract does have a beneficial effect, but just that this study certainly can’t prove it.

(It should also be noted that neither of these studies which I’ve seen cited as evidence for Reishi Mushroom Extract, actually use Reishi Mushroom Extract…)

A Morning’s Haul of Wild Mushrooms

Don’t Put Chemo in Your Coffee

Just to make it clear, there is ZERO evidence that Reishi Mushroom Extract could be an effective treatment for cancer patients, either in combating cancer directly or indirectly by boosting sufferers’ immune systems.

If, however, we lived in a parallel universe where there was strong evidence that Reishi Extract contained potent cancer fighting chemicals, this still wouldn’t mean that it would be a wise idea for a healthy person to consume it on a regular basis in the hope of preventing cancer.

Prevention is better than a cure, yes. But this doesn’t mean that you should start taking cancer medication on the off chance!

Chemotherapy and Radiotherapy are two of the most widely effective treatments for many forms of cancer, but it would be highly inadvisable to start doing daily sessions of both as a preventative measure.

Obviously, these are extreme examples, but this is basically true of any medication. A life saving drug to a seriously ill person, is usually a toxic poison to a healthy one.

For more on this check out my article on “The differences between Supplements vs Medications and Why it Matters“.

Do Eat Mushrooms

Though I may not be a fan of Reishi Mushroom Powder, I do recommend eating mushrooms.

Button mushrooms, portobello, oyster, porcini, even reishi, maitake and shiitake, are all good, healthy food choices.

Will they cure all known disease and prevent you from getting cancer? Probably not. But they are low in calories, high in fibre, and packed full of vitamins and minerals.

I am still pretty sure that any perceived benefits of drinking mushroom teas and shakes is probably placebo, but there is also the possibility that in some cases benefits are gained from correcting vitamin of mineral deficiencies.

Reishi Mushrooms are a rich source of zinc, copper, iodine, selenium, and iron, plus B vitamins, amongst others. Deficiency in these essential nutrients can result in symptoms of fatigue, reduced immune functions, slower recovery from exercise, etc.

Study after study have shown however, that vitamin and mineral supplements are not the best way to go however. Their use is associated with increased cancer risk and reduced life expectancy.

We don’t quite know why this is. Perhaps it’s too much of a good thing, perhaps it gives people the green light to skip whole foods and they end up missing out on important nutrients not covered by the pills and powders.

I’m sure we’ll work it out one day, but in the meantime, the evidence still shows that supplements suck and whole foods rock, so you’re much better off just buying whatever mushrooms are available in your local area, and sauteing them with some herbs and butter.

(I also highly recommend going foraging for mushrooms, it’s great fun, and great exercise. Just make sure you go with someone who knows what they are doing so you don’t poison yourself…)

Stir fried Shiitake Mushrooms

Hyeon-Jeong Suk CC BY 2.0, via Wikimedia Commons

Some Mushrooms Really Are Magic

Final note, while we’re on the topic of mushrooms, is that there is a growing body of interesting research into the effects of psilocybin, the psychoactive chemical found in a variety of mushroom species.

Again, it’s too early to say definitively how effective they are, but they do seem promising potential treatments for depression and anxiety.

One thing that can’t be argued is that psilocybin definitely has effects that go way beyond placebo!

Examining the curious genes behind ‘magic mushrooms’

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