Mushrooms may contain unusually high amounts of two antioxidants that some experts believe could help fight aging and improve health. A study from Penn State researchers found that mushrooms have high amounts of ergothioneine and glutathione, both important antioxidants.

“What we found is that, without a doubt, mushrooms are the highest dietary source of these two antioxidants taken together, and that some types are really packed with both of them,” said Robert Beelman, professor emeritus of food science and director of the Penn State Center for Plant and Mushroom Products for Health.

“There’s a theory — the free radical theory of aging — that’s been around for a long time that says when we oxidize our food to produce energy there’s a number of free radicals that are produced that are side products of that action and many of these are quite toxic,” said Beelman.

“The body has mechanisms to control most of them, including ergothioneine and glutathione, but eventually enough accrue to cause damage, which has been associated with many of the diseases of aging, like cancer, coronary heart disease and Alzheimer’s,” he continued.

He added that the researchers also found that the amounts of the two compounds varied greatly between mushroom species, and that among the 13 species tested, the porcini species, a wild variety, contained the highest amounts of the two compounds.

The more common mushroom types, like the white button, had less of the antioxidants, but had higher amounts than most other foods, Beelman said.

The amount of ergothioneine and glutathione also appear to be correlated in mushrooms. For example, mushrooms that are high in glutathione are also high in ergothioneine, and cooking doesn’t significantly reduce the compounds.

“It’s preliminary, but you can see that countries that have more ergothioneine in their diets, countries like France and Italy, also have lower incidences of neurodegenerative diseases, while people in countries like the United States, which has low amounts of ergothioneine in the diet, have a higher probability of diseases like Parkinson’s Disease and Alzheimer’s,” said Beelman.

“Now, whether that’s just a correlation or causative, we don’t know,” he continued. “But, it’s something to look into, especially because the difference between the countries with low rates of neurodegenerative diseases is about 3 milligrams per day, which is about five button mushrooms each day.”

The study’s results were published in Food Chemistry