Medicinal Mushrooms #2 – Coriolus Versicolor (PSP/PSK) – the number one anti-cancer mushroom


Coriolus Versicolor or Turkey-tail mushroom (Yun zhi in Chinese)

Updated 21 December 2013

Coriolus Versicolor is also known as Turkey-tail mushroom, Tametes Versicolor, Yun Zhi (in Chinese), Karawaratake (in Japanese).  Extracts of the mushroom are known as PSP (polysaccharide peptide) and PSK (polysaccharide K, or Krestin).

In the 1980s, the Japanese government approved the use of PSK for treating several types of cancer and PSK is a best-selling anti-cancer drug in Japan as a complement to surgery, chemotherapy and radiotherapy. PSP was discovered more recently in China.

How it works:

There are two types of immune response in the human body:  Cytokine T-Helper Cell 1 (TH2) and Cytokine T-Helper Cell 2 (TH2) responses.

A Cytokine TH1 response is a cellular response, i.e. originating from cells.  Cytokine TH2 response is a humoral response, i.e. originating from the body fluids.

A TH1 response is anti-tumour, anti-viral and anti-bacterial.  It also activates Natural Killer or NK cells.  A TH2 response is pro-inflammatory (e.g. causing fever), and tends to predominate during infections, e.g. hepatitis.  Levels of NK cells are decreased during TH2 response.

TH1 and TH2 responses are mutually-inhibitory, that is, they cannot exist at the same time.  TH1 responses tend to peak between mid-morning to early night.  TH2 responses tend to happen from night-time to early morning – this probably accounts for why inflammatory conditions like asthma or rheumatoid arthritis flare up during these hours.

The body is considered to be in a state of balance when TH1 levels are in a state of shifting equilibrium with TH2 levels.

However, if a body moves from TH1 response to TH2 and then does not shift back, the system becomes locked into an inflammatory state.  Why is this bad?  The reduction in TH1 levels means a reduction in NK cells and the body’s ability to destroy cancer cells.  The TH2 inflammatory response stimulates the creation of new blood vessels around damaged tissues, and this can lead to tumour growth.

Coriolus versicolor is able to make the shift from TH2 to TH1 through its polysaccharides peptides.  It also increases Natural Killer cells, and CD8+ T-cells (a type of white blood cell) that can kill cancer cells

Why you should make Coriolus part of your anti-cancer toolkit

The Coriolus extract, PSP, has been shown to have immune boosting and modulating effects, and anticancer properties in both pre-clinical experiments and clinical trials.

It has been also been shown to reduce the side effects of radiotherapy and chemotherapy.

It is supported by over 400 medical studies including MD Anderson Cancer Center and the National Cancer Institute in the US.

Here is an article on the use of Coriolus on breast cancer patients undergoing chemotherapy and radiotherapy:

What you should look for when buying Coriolus

Amount of active ingredients

You should look for the amount of polysaccharides and beta-glucans – these are the active ingredients in any medicinal mushroom.


This is a measure of how absorbable the product is, by the body.  In general, mushrooms in powdered form are not readily absorbable because of the chitin (coating) of the mushroom.  You want an extract.

Potency of extract

The higher the better.  This is usually expressed in terms of the amount of active ingredients, e.g. 50% polysaccharides.

Proof of authenticity

You want a product that has a Certificate of Analysis from a third-party lab, confirming the percentage of polysaccharides and beta-glucans.

How the mushroom is grown

For Coriolus, you want a product that is grown on wood logs, not on a powdery substrate.  If it is grown in a substrate (like sawdust or rice powder), it is hard to separate the roots of the mushroom (the mycellium) from the substrate, so the end product is mostly substrate.

To illustrate how indigestible mycelia is, please read this article:,9171,1957474,00.html – on a newly developed building material, comparable to plasterboard, but made from dried mycelia – rock hard, stronger than concrete, fire resistant, water resistant etc. And this is basically the same stuff that is served to innocent supplement customers, in powder form …

What about products that claim to be “full spectrum” with no unwanted shift of effect because they contain the whole biomass and not just an extract?

This is a tricky one because I sorted out my hayfever using a biomass Reishi product, and Paul Stamets, the Mushroom Guru, has a range of mushroom products which are biomass.  He also has a range that are extracts.
I had the following discussion with Syds Marra of Oriveda, and here is a paraphrase:
“Let’s look at the claims.
Some producers point out that their products are ‘complete, uncompromised full-spectrum products, not just a concentrate of a few ingredients’. This is partly true, but this uncompromised full-spectrum product is mostly useless because it is mostly indigestible.
A well extracted full-spectrum mushroom product is basically the complete mushroom but without the chitin ‘locks’ on the bioactive ingredients, so fully bioavailable. By using carefully chosen strains and cultivation methods, together with high quality extraction protocols, a standard quality can be achieved, and the producer can claim e.g. “not less then xx % of polysaccharides”. This claim is fully verifiable and therefore can be printed on the governmentally supervised ’supplement facts’ label.
The ‘effect’ some companies are referring to when they state ‘no unwanted shift of effect’ , is actually the therapeutic effect of an extracted mushroom product, because all research of therapeutic effects and all traditional use has been using extraction in some way, never raw mushrooms (let alone ‘biomass’ – there is no such thing in TCM). 
There is a very good reason all scientific research and all traditional use is using extraction (even making tea or soup is a crude form of extraction) when utilising mushrooms:  we simply cannot digest non-extracted mushroom products very well, so the therapeutic effect is poor at best.”
Where to buy Coriolus or PSP/PSK

I started out using Coriolus from MRL, but I now prefer Coriolus/PSP from Oriveda.  To the best of my knowledge, it’s the best PSP available on the market, at the moment.

Here’s how I came to this conclusion:

19 Sept 2013 – just found a source of PSP – Oriveda. The company claims it is the most powerful form of PSP in the world. Hmm … big claim. And their prices are lower than Inforce’s PSP, although their capsules only contain 350mg vs Inforce’s 450mg. I’ve written to them to ask them how they substantiate their claim and prices. I’d be interested in trying the Oriveda PSP because I love value for money.

Here’s the link to order from Oriveda (affiliate link because of my confidence in what they are providing):

20 Sept 2013 – I got a reply from Oriveda within 2 hours. I’d asked to see their Certificates of Analysis and also asked how they managed to charge the lowest prices (so far) for the world’s most potent PSP. I also e-mailed a company that sold Inforce Immune Builder and asked to see their CoA.

I was impressed by the speed of Oriveda’s reply and also its comprehensiveness and transparency. CoAs were produced which showed a breakdown of the amount of polysaccharides, beta-glucans and other minerals.

Oriveda were honest about how they kept their prices low – it seems as if it might be a case that the competition has kept the prices artificially high. (Which is a shame because cancer patients are being ripped off by companies that charge a lot for their products even when they don’t cost that much to produce!)

The e-mail I received from the InForce reseller said that InForce never sent out their CoA. I have since found out InForce is an MLM scheme.

So at the moment … my instincts say Oriveda is the real deal. Which is why I’ve ordered their PSP and Reishi. It costs about as much as the MRL product, and I know I’m getting a therapeutic dose. With cancer you cannot afford to pussyfoot around with prophylactic dosing – you have to hit hard and powerfully. The PSP and Reishi should last me about 2 months.

Oriveda also offer other mushrooms like Cordyceps, Chaga and Agaricus Blazei, all with their guarantee of highest potency.

Other reputable companies producing medicinal mushrooms are: Mushroom Science and Sayan Health and of course, Paul Stamets’ Fungi Perfecti (Host Defense Mushroom) range.

Here is a link to a monograph on Coriolus, on the Oriveda site:


Here’s what I wrote pre-20 September 2013 (information is no longer valid)

I buy my Coriolus from Mycology Research Laboratories.  This is a powder made from the young fruitbody and mycellium. [20 Sept – I can no longer recommend the powders as they are not potent enough for therapeutic dosing, i.e. for serious illnesses like cancer – see update below.  Also, in terms of bioavailability, extracts are better]

However, the extracts – PSP and PSK are more potent. Here is an article on the Mushroom Studies site, comparing the fruitbody to the extracts:

Inforce Immune Builder (with PSP and PSK) has a 4-star rating from the mushroomstudies site.  The basic PSP/PSK version retails at about £24.95 (on Amazon) for 60 x 450mg tablets = 27,000mg per bottle = 27g [can this be right?].  This means 1g of Inforce Immune Builder costs 0.92p.

[there is a more expensive Platinum version which contains just PSP]

Coriolus Versicolor from MRL costs me £60 for a 250g tub (special price from my herbalist, otherwise it costs £75 on the MRL site).  This means 1g of MRL Coriolus costs 0.24p

I’ve found yet another source of Coriolus that might be a good alternative to MRL and ImmuneForce.  It’s a 10:1 extract [10 lbs of mushroom concentrated into 1 lb], and is from a company called Hybrid Herbs.  Their Coriolus costs £59.97 for 8oz (226.796g).  Which means 1g of the Hybrid Herbs version costs 0.26p.  However, it is 10 times more concentrated than the MRL version, so works out cheaper as you can use less.  I asked Hybrid Herbs where they got their Coriolus from and it’s from remote forests near the Russian/Siberian border.

Inforce Immune Builder seems the most expensive, but it is pure PSP/PSK.  It’s possible to get away with 1-2 capsules 2/3 times per day for immune maintenance which works out to 1-3 bottles of InForce/month.  However, for those with serious health issues, the recommended dose is 2-4 capsules 3 times a day.  That’s about 3~6 bottles of inForce/month.  Still, anything that alleviates the symptoms of chemotherapy and radiotherapy are worth the money.

[20 Sept 2013 – I can no longer recommend Inforce Immune Builder as there is no Certificate of Analysis of the amount of active ingredients, the polysaccharides or the beta glucans in their products]