Eating mushrooms may dramatically cut risk of cognitive decline

Melissa Breyer MelissaBreyer

March 12, 2019

© nito

New research finds that seniors who ate mushrooms twice weekly had 50% reduced odds of having mild cognitive impairment. 

People often ask me if mushrooms have much nutritional benefit. We’re always hearing about the remarkable superpowers of kale and blueberries and their dazzling cousins, but what about the humble fungi?

So I’m here to tell you this: Eat mushrooms! They are superstars.

I first came upon this profound bit of wisdom in 2017 when researchers found that mushrooms have remarkably high amounts of two potential antiaging antioxidants. And now, new research from the National University of Singapore backs it up.

In a six-year study, the researchers found that seniors who ate just two portions of cooked mushrooms a week were half as likely (than those who ate mushrooms less than once a week) to have mild cognitive impairment (MCI). The association was independent of age, gender, education, cigarette smoking, alcohol consumption, hypertension, diabetes, heart disease, stroke, physical activities, and social activities.

The Alzheimer's Association describes MCI as a "slight but noticeable and measurable decline in cognitive abilities, including memory and thinking skills," noting that someone with MCI is at an increased risk of developing Alzheimer's or another dementia.

© National University of Singapore

A portion was defined as around three-quarters of a cup of cooked mushrooms with an average weight of 150 grams (five ounces). Which is pretty remarkable; often times studies like this are using extracts, or the amount to be consumed is unrealistic. Here, they found that even a single small serving of mushrooms weekly may still be beneficial to reduce chances of MCI.

The study was conducted from 2011 to 2017, and was based on data from more than 600 Chinese seniors over the age of 60 living in Singapore. The research included six popular mushrooms (shown above), including golden, oyster, shiitake and white button mushrooms, as well as dried and canned mushrooms. However, the University notes, it is likely that other mushrooms would also have beneficial effects.

As previous researchers have surmised, the team believes the magic here is due to a specific compound found in almost all varieties. "We're very interested in a compound called ergothioneine (ET)," says Dr Irwin Cheah, Senior Research Fellow at the NUS Department of Biochemistry. "ET is a unique antioxidant and anti-inflammatory which humans are unable to synthesise on their own. But it can be obtained from dietary sources, one of the main ones being mushrooms."

And while at this point the relationship between mushrooms and cognitive health is still causal, 
an earlier study by the team found that plasma levels of ET in participants with MCI were much lower than healthy individuals of the same age. That research led to the idea that increasing ET consumption through eating mushrooms might possibly promote cognitive health.

"This correlation is surprising and encouraging. It seems that a commonly available single ingredient could have a dramatic effect on cognitive decline," says lead author Assistant Professor Lei Feng, from the NUS Department of Psychological Medicine.

The next step the researchers hope to take is to perform a randomized controlled trial to assess phytonutrients like ET’s relationship to cognitive health. “Such interventional studies will lead to more robust conclusion on causal relationship,” notes the University ... even though I’m already sold.

The research was published in the Journal of Alzheimer's Disease. For more information, visit the National University of Singapore newsroom.