When surfing the internet for background on the Agaricus blazei Murrill (ABM) mushroom, one is confronted with fantastic stories, about isolated Brazilian rainforest Indians in the early 1960s, free from diseases and with unusual long lifespans, and a Japanese researcher named Takatoshi Furumoto who, intrigued by the unusually healthy Indians started an investigation. He discovers that the source of their good health must be in their diet, in particular a mushroom they eat often, a mushroom never seen before in the world.
This story is most likely made up by Japanese marketeers to create some background for the healing powers of this mushroom, a sister of the very common white button mushroom, the Agaricus bisporus. The Japanese scientist somehow never left a trace in scientific publications and the mushroom has never been eaten in the Piedade region, where, even nowadays, it is not commonly found.
In fact this mushroom was already known in the late 19th and early 20th century in the US, where it was very popular because of its excellent almond flavor and cultivated widely for the table – the almond mushroom. It was officially known as Agaricus subrufescens since 1893. After a few decades of success the white button mushroom (Agaricus bisporus) took over its place as the most popular edible mushroom.
In the late 1940s the American mycologist W.A. Murrill discovered an interesting mushroom growing on the lawn of his friend R.W. Blaze in Florida. He did not recognize the species and, in honor of his friend, named it Agaricus Blazei. And now the confusion starts…
To cut a long story short, the mycologists were mixing up very similar looking mushrooms and in the end had to use DNA-profiling to put an end to all the quarrels.
Here are the mycological facts:
The mushroom that received the name ‘Agaricus blazei Murrill‘ was in fact the ‘Agaricus silvaticus Schaeffer‘. It is not a medicinal mushroom.
The ‘Agaricus brasiliensis‘ (another name given to the actual medicinal mushroom in 2002) turned out to exist already (classified in 1830) and is also not a medicinal mushroom.
The actual medicinal mushroom incorrectly named Agaricus blazei/Agaricus brasiliensis should in fact be called Agaricus subrufescens, the oldest taxonomical name. However, this medicinal mushroom and its derivatives are still researched, marketed and sold under the name Agaricus blazei Murrill (ABM) and Agaricus brasiliensis worldwide. Very confusing.
This mushroom has mainly been studied in Japan. The main ABM based supplements and pharmaceuticals are also produced in Japan, until recently. In Japan the industry based on this medicinal mushroom is worth well over 600 million USD annually and over half a million people are consuming ABM supplements every day (2002 estimate). Right now ABM is the best selling medicinal mushroom in Japan.
In the past decades cultivating has been perfected. The majority is being grown in Brazil (keeping alive the marketing story, of course) and China, but the ABM is also found more and more in Europe and the USA. This mushroom, like all Agarics (including the button-mushroom) absorbs heavy metals like cadmium and lead very easily, therefore one should always verify the levels of these toxins before purchase. Never rely on the ‘organic’ label – this label does not guarantee the product is free from heavy metals, only pesticides. And since all mushrooms accumulate heavy metals from the soil and the air, high levels are very common. Only properly tested mushrooms should be considered.
Furthermore, all Agarics contain agaritine, a carcinogenic substance. However, despite the statements of some supplement producers, the chance agaritine is found in an extract of the mushroom is zero. It oxidizes very fast upon storage, and totally degrades after 48 hours in water with exposure to air. It also decomposes very fast upon cooking (up to 90% reduction) and freezing (up to 75% reduction).
Since these processes are part of the standard extraction procedures it is quite clear that no agaritine will be found in extracts. Non-extracted ABM products (powdered fruitbodies, myceliated biomass) can be a different story, though. We recommend to request a Certificate of Analysis from the supplier (not to be confused with a ‘spec sheet !).
Compared to the other medicinal mushrooms the ABM is a benjamin. The Japanese started researching the mushroom in the late 1960s and began isolating active components soon afterwards. No other medicinal mushroom has such a high percentage of polysaccharides – the Oriveda extracts e.g. contain between 60-70% of polysaccharides, of which over 60% are pure (1>3)(1>6)Beta-D-Glucans.
These specific glucans are found in all medicinal mushrooms and according to research they are mainly responsible for the immune balancing, anti-allergic and cholesterol/blood-pressure lowering effects. They are also effective in lowering the side effects of heavy medication such as chemo and radio therapy, and might help in preventing metastasis. The development of NK cells, T cells and macrophages, to name a few, is improving.
ABM also inhibits the enzyme aromatase, which is associated with the development of breast cancer.