Ergothioneine: A New Vitamin?

Ergothioneine was discovered a century ago but ignored until recently when researchers found that we have a transporter protein in our bodies specifically designed to pull it out of our diets and into our tissues. This suggests that it plays some important physiological role, but what does it do? Well our first clue was the tissue distribution. Ergothionine concentrates in parts of our body where there’s lots of oxidative stress—the lens of our eye and the liver, as well as really sensitive areas like our bone marrow and seminal fluid in men. Researchers guessed that it might function as a so-called “cytoprotectant,” a cell protector, and that’s indeed what was found.

Not only does ergothionine get into the nucleus of our cells to protect our DNA, it can get into our mitochondria, the power plants of the cell. Ergothieneine appears to function as a potent intra-mitochondrial antioxidant. Why is that important?  In my video Mitochondrial Theory of Aging I quote one of the greatest biochemists of all time:

“Aging is a disease. The human lifespan simply reflects the level of free radical damage that accumulates in cells. When enough damage accumulates, cells can’t survive properly anymore and they just simply give up.”

First proposed in 1972, the Mitochondrial Theory of Aging suggests that it’s free radical damage to our cells’ power source that leads to a loss of cellular energy and function over time. It’s a little like charging your iPod battery over and over again; every time you charge it the capacity gets less, and less. In my Stopping Cancer Before it Starts DVD, I go into detail about the quantum biology of oxidative phosphorylation, but in a nutshell the oxygen we breathe may get a hold of an electron we ate that was pumped with energy by plants (thanks to photosynthesis). The oxygen molecule is thereby transformed into what’s called superoxide, which can damage (oxidize) our delicate cellular machinery. Basically we’re rusting—that’s what rust is, the oxidation of metal. Scientifically, aging has been considered the slow oxidation of our bodies. Like those brown age spots on the back of people’s hands? That’s just oxidized fat under the skin. Oxidant stress is why we get wrinkles, it’s why we lose some of our memory, and it’s why our organ systems break down as we get older.

How do we slow down oxidation? By eating foods containing anti-oxidants. If you want to know if a food has a lot of antioxidants in it simply slice it open, expose it to air—expose it to oxygen–and see what happens. Does it oxidize? Does it turn brown? Think about our two most popular fruits: apples and bananas. They turn brown right away—not a lot of antioxidants inside there. How do you keep your fruit salad from turning brown though? Add lemon juice, which has vitamin C in it, an antioxidant, that can keep your food from oxidizing and can do the same thing inside our bodies.

For an introduction on where antioxidants can be found in our diet, see Antioxidant Content of 3,139 Foods and Antioxidant Power of Plant Foods Versus Animal Foods.

Here’s the catch: many antioxidants can’t penetrate through the mitochondrial membrane into the mitochondria. They can protect the rest of the cell including our DNA, but they can’t get access into the power plants of our cells and therefore may be helpless to slow down the aging process. Ergothionine, however, is allowed access into our mitochondria. Where is it found in the diet? Click on the above video.

Other examples of the magic of mushrooms can be found in:

Probably best to cook them though, see Toxins in Raw Mushrooms?

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my videos for free by clicking here and watch my full 2012 presentation Uprooting the Leading Causes of Death.

Image credit: sielju / Flickr

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W. C
W. C8 months ago

Thank you.

William C
William C8 months ago


Duane B.
.4 years ago

Thank you for sharing.

Spirit Spider
Spirit Spider4 years ago

Mmmmmmushrooms! Makes sense to me :-)

heather g.
heather g4 years ago

Thanks Dr Gregor - your info is consistingly informative. Also thanks to Heidi about preferably eating the Japanese mushrooms eg Maitake, Shitake. There are even some supplements made from these - but you can't beat real food !

Mitchell D.
Mitchell D4 years ago

Happily. my wife and I like mushrooms, in fact bought some earlier today.

Carol D.
Past Member 4 years ago

I used to eat raw mushrooms but doesnt sound like a good idea but i will buy more white button mushrooms and cook them as i love mushrooms Great taste

Richard T.
Richard T4 years ago


Heidi Aubrey
Heidi Aubrey4 years ago

I hate when I run out.

continued and important if you supplement.

Some unreputable suppliers grow their mushrooms on waste lumber which has been treated with very toxic chemicals and heavy metals to keep them from rotting(think: the beams in your house) or they'll grow them on raw sewage which is acutally illegal.

Point is, if you choose to supplement vs. eating fresh(saute'd) make sure your supplement states the medium its grown on. Good ones wiil actually be organic medium.

Heidi Aubrey
Heidi Aubrey4 years ago

Don't worry about companies trying to sell you this product. It is extraordinarily difficult to exract. In fact there is only one company that has and I think it went out of business(not sure though)

What Mr. Greger failed to mention they are found in greater concentrations in some mushrooms while completely, totally, absolutely lacking in others.

The mushrooms that you can eat or supplement with that have the very greatest concentration of this very importantant phytonutrient are: Maitake, Shitake and another one I forgot. However a great, not very great, source is the plain old button mushroom. And if your eating them vs. supplementing, you don't need to eat that much of them to get the recommended dose(they have actually determined a recommended dose for cell survival) and it can be cooked and survives just fine. Only 10 grams. Thats about the amount on top of a Swiss style hamburger(no I don't recommend eating hamburgers: only to give you an idea of the amount you need). Or simply slice and saute one or two buttons and you will have, then, a very great source. You only need a few slices or so.

I am glad he brought this to the forefront though. I have known about ergothioneine for many years. Its the nature of my work and education. Personally, I supplement with Shitake mushroom daily. If you choose to do this as well, make sure you know the medium the Shitake(or any mushroom for that matter) was grown on. Some unreputable suppliers grow it on wa