3 Mushrooms (Fungi) That BOOSTS Your Immune System


Mushrooms have been used medicinally in Japanese medication for eons.

Now Western medication is starting to catch up, because the therapeutic properties of mushrooms are being demonstrated scientifically.

The three particular varieties with the best well being advantages are Shitake, Reishi and Maitake. All three have highly effective results on the immune system and all three act as medication.

When you think about it for a minute, it makes an awful lot of sense that mushrooms have medicinal properties. Why? Because mushrooms are fungus. They scavenge on organic matter. Where do you find them? Growing on decaying wood, or worse (cow patties, anyone?).

That means they are able to absorb and then safely eliminate toxins.

I don’t know about you, but I’d like to put them to work doing that in my own body, and eating them appears to be a great way to do it.


In addition to being loaded with vitamins, Maitake has a special polysaccharide component called Beta 1,6 glucan, a very close relative of the Beta 1,3 glucan in the Shiitake (see below). Beta-glucans stimulate the immune system.1 I’ll tell you how this works in a moment.

Many of the compounds in the cell structures of mushrooms are actually used as adjunctive cancer treatments throughout Asia—in fact, Maitake is approved by the Japanese government for just this purpose. It’s especially good for counteracting the toxic effects of radiation and chemotherapy, such as extreme fatigue and nausea.


The Shiitake mushroom is one of the most widely cultivated specialty species of mushroom in the world, and is deeply valued for its medicinal effects, not to mention the fact that it tastes delicious.

It contains enzymes and vitamins that do not normally appear in plants—like all 8 essential amino acids and one of the essential fatty acids, linoleic acid. The caps contain more nutrients than the stems.

This superstar mushroom contains beta 1,3-glucan, a polysaccharide that has potent immune-stimulating effects,2 and a close relative of the beta 1,6 glucan found in Maitake (see above).

When beta glucans bind to immune system cells like NK cells, T-cells and macrophages, the activity of these cells is increased. No one is quite sure of why, but my friend Bob Rountree, MD, author of Immunotics, speculates that the beta glucans “trick” immune system cells into thinking they’re under attack.3

Mushrooms are, after all fungus, and maybe the cells think the harmless little critters are dangerous. Who knows? Point is: the immune system is stimulated by them.

Many studies4 have confirmed beta glucan’s wide range of protective effects, including improved resistance to infections, liver-protection and cardiovascular benefits. It also appears to help inhibit tumor growth in mice.


Sometime in the third century BC, the Chinese Emperor Shih Huang was reputed to have sent a fleet of ships to search for a mushroom called the “Elixir of Immortality”. That mushroom? The Reishi. It’s special chemical make-up was thought to be a tonic for a long and healthy life. In traditional Chinese medicine, Reishi is still considered to be among the highest class of tonics.

Reishi’s beneficial components—specifically ganodermic acids classified as triterpenopids, plus a number of polysaccharides—seem to benefit everything from blood pressure to liver detoxification to adrenal function.

Even the conservative and highly regarded Memorial Sloan-Kettering Cancer Center has Reishi mushroom listed on its website, stating that Reishi mushrooms stimulate the immune system through their positive effect on macrophages and other immune compounds.

Sloan-Kettering also references clinical studies showing that Reishi enhances the immune responses in advanced-stage cancer patients.

Reishi mushrooms appear to be a natural stress-buster. According to Dr. Roundtree, Reishi is the mushroom of choice for people under extreme physical or emotional stress.

Crimini (White Button Mushrooms)…

I almost omitted crimini mushrooms from the list completely—I mean, after all, how could these little prosaic mushrooms possibly hold a candle to the downright medicinal value of their famous siblings?

But crimini mushrooms are super dense with nutrients. One 5-ounce serving (dry weight before cooking) gives you over 50% of the daily value for the cancer-fighting trace mineral selenium, 40% of the daily value for riboflavin, 35% of copper, 30% of niacin, 20-25% of pantothenic acid, phosphorus and zinc, plus 10-15% daily value of manganese and thiamin.

They also have trace amounts of magnesium, calcium, folate, B-12 and iron”.

Now I don’t feel so bad counting mushrooms as a vegetable!

I gave mushrooms a “STAR” rating in my best-selling book, The 150 Healthiest Foods on Earth.5 Don’t dismiss this common vegetable as “nutritionally empty”. It’s anything but.


Goodridge HS, et al. Beta-glucan recognition by the innate immune system. Immunol Rev 2009; 230(1):38-50

Akramiene D, et al. Effects of beta-glucans on the immune system. Medicina (Kaunas) 2007; 43(8):597-606

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