Research Stories

by Christine Lambrakis

Edible mushrooms are a versatile functional food and have been touted as a way to preserve youth, longevity and overall health for centuries. Now nutrition researchers from Arizona State University and Pennsylvania State University are finding that they may even help boost the immune system and reduce inflammation, especially in the colon.

Keith R. Martin, ASU assistant professor in nutrition, along with his Penn State colleagues, experimented with various types of mushrooms, from the more common white button to the exotic like shiitake and oyster, to see what sort of effect they had on the immune system. Their paper was published in late February in BMC Immunology, a peer reviewed online journal.

"We found that the white button mushroom seemed to be the most effective in boosting the immune system, which is good because they are the most affordable," said Martin.

The ASU and Penn State researchers performed a series of experiments adding five mushroom varieties to the diets of mice. The amount of mushrooms consumed by the animals is equivalent to roughly 2.5 cups of raw mushrooms daily for humans, according to Martin.

The researchers found that the effects on healthy animals were much weaker than the effects seen in isolated immune cells in lab studies with all the mushroom types. Rodents that ate a diet consisting of 2 percent white button mushrooms for four weeks showed no change in their immune system and no signs of toxicity.

However, when the researchers fed the animals a chemical that triggers colon inflammation and can promote the growth of colon tumors, the rodents that had white button mushroom in their diet were protected from weight loss and colon injury.

"I would like to test whole mushrooms again with inflammation and may try a small human study," says Martin, "and I anticipate a beneficial effect in humans, too."

This study was funded by The Mushroom Council.